365 Days of Astronomy

September 2nd: Exótico Cielo Profundo: By the border of Vulpecula-Sagitta

kortney.hogan — Thu, 02 Sep 2010 11:00:37 +0000

Date: September 2, 2010

Title: Exótico Cielo Profundo: By the border of Vulpecula-Sagitta

Podcaster: Julieta De Simone Shecre

Description: An observational proposal in which we will be moving by the surroundings of the equator of our galaxy, driving along the shared border of the small constellations called Vulpecula and Sagitta, studying visual characteristics, astrophysical data and some history of selected objects, where the naked eye and different instruments will offer us different perspectives and details. We will notice different aspects and colours and we may even note familiar shapes…

Bio: Sur Astronómico is a website in Spanish managed by Enzo De Bernardini. The Exótico Cielo Profundo (Exotic Deep Sky) section was created by Rodolfo Ferraiuolo and Enzo De Bernardini and it is devoted to the visual observation of select objects from the deep sky. Having started in January 2008 and having received great approval from the amateur public, getting a lot of comments in the forum of the group, the periodic articles of the section were shaped to be written on a book.

Today’s sponsor: This episode of “365 Days of Astronomy” is sponsored by no one. Please consider sponsoring an episode by clicking on the ‘donate’ link to the left.

Transcript:

By the border of Vulpecula-Sagitta
Area: Sagitta (the Arrow), Vulpecula (the Fox)

On this observational proposal, we will be moving by the surroundings of the equator of our galaxy, driving along the shared border of the small constellations called Vulpecula and Sagitta. These constellations have a lot to show and that is why we chose them. We hope that by exploring this area of varied difficulty you’ll be surprised by the richness of objects and you’ll enjoy many nights of observation.

Our starting point will be CR 399. In 1931 the Swiss astronomer Per Arne Collinder introduced this object as the 399th open cluster of his catalogue but, even though it is still on discussion, it looks as if it was just a fantastic asterism of ten stars between the 5th and the 7th magnitudes. It is situated on an area of low, irregular absorption, which is full of stars, by the south-western end of Vulpecula, limiting with Sagitta, almost halfway between the white star of 5th magnitude – 9 Vulpeculae – to the east-south-east, and the blue/white star of magnitude 4.8 – 1 Vulpeculae – to the north-west.

It is commonly called in three different ways. Al-Sufi Nebula after the Persian astronomer Abu’l-Husayn al-Süfï (reduction and adaptation of his real long name). He registered it in the middle of the 10th century, as a small blot. Brocchi’s Cluster because of the amateur astronomer and great variable star observer, Dalmiro Francis Brocchi, who stated it in one of the 1920’s important charts for variable star observation that he was preparing for the AAVSO, the American Association of Variable Star Observers (his mapping work earned him the Merit Award of the AAVSO in 1942). And the most accepted one, Coathanger, because of its distinctive star pattern.

It turns out to be an interesting asterism for small apertures and even better for some simple binoculars, with which we will be able to observe, even with the presence of the moon, its ten colourful component stars contrasting and standing out among fifteen other fainter stars. Its coathanger shape, observed in the position it should be hung from the southern hemisphere, is made up of six practically aligned stars oriented towards the west, and four other stars with the shape of a hook, by the centre, to the south.

With a 3.6 combined magnitude, it can be easily spotted from dark places as a faint nebulous patch. By observing it with a 4” telescope, we will miss part of its structure because of its size, and we will see about forty fainter stars around its components, forming pairs, triplets and lines.

Going to the east, at about 17 arcminutes from 7 Vulpeculae, the star that is part of one of the ends of the Coathanger, we will find the open cluster NGC 6802, our second stop. With a magnitude of 8.8, a diameter of 3.2 arcminutes and classified as L1, this small galactic cluster was discovered by William Herschel in 1784. It is 3600 light years away from the Earth and it contains more than 60 stars with a magnitude from 13 onwards.

Visible with a 2.3 inch, 30x refracting telescopes as a faint luminosity, by observing it with a 5 inch Schmidt-Cassegrain telescope it will have little change, appearing as a dim oval blot. With an 8” telescope, we will see it with low surface brightness, starting to become resolved, and virtually oriented from north to south. With a 12” we will be able to observe about 20 stars over a misty background, of about 3 x 1.5 arcminutes. The cluster, which is situated in an area of high absorption, is found in the middle and to the south of two nice stellar pairs: one of 9th and 11th magnitude, 6 arcminutes to the north-east, and the other of 9th and 10th magnitude, 6.3 arcminutes to the north-west of the centre of the cluster.

We are now going to look for M27. In order to find it, we must practically look 3 degrees to the north of the red giant star of magnitude 3.5, Gamma Sagittae, and 23 arcminutes to the south and a little to the east of the yellow star of magnitude 5.7, 14 Vulpeculae.

It is the first planetary nebula to be discovered in July 12, 1764 by the well known French astronomer Charles Messier, who discovered it as a starless oval nebula. It is known by the name given in John Herschel’s description in 1833, Dumbbell, because of its shape. It is also known as Apple Core since its appearance recalls that of a bitten apple around its outline. It is of 7.2 magnitude, surface brightness of 11.1 and apparent size of 8 x 5.7 arcminutes which expands vaguely in photographs up to a diameter of 17 arcminutes.

Classified as 3+2, it appears with a position angle of 119 degrees, a negative heliocentric radial velocity of 42 km/s has been calculated, its real diameter would reach almost 6 light years, and it is found at an arguable distance of about 1250 light years. Its minimum estimated age is of about 3500 years, since the gas of the shell, in its central area, expands almost 7 arcseconds per century.

We observe the nebula practically on the equatorial plane, similar to an hourglass, and if we observe it from one of its poles, its shape would probably be annular.

In the 1970’s, a faint companion of the warm central star of 17th magnitude was discovered, with a separation of 6.5 arc seconds, and a position angle of 214 degrees. The real separation between both stars would be about 2500 AU.

Being visible from a rural place with 7 x 50 binoculars or finder scope, as a tiny faint dim blot, with a small refracting telescope it will be small, quite rectangular and faint. However, with 15 x 70 binos, it will surprise us as a more resolved pale-grey blot, very pretty and with a diameter of about 7 arcminutes.

With a 4”, it will start becoming one of the best planetary nebulae for visual observation, appearing with its typical dumbbell or weight shape, oriented from north-north-east to south-south-west, with a pale-grey shade and even brightness, contrasting with the rich stellar field, improving its borders and enlarging its size by using avert vision. With an 8” refracting telescope, we will notice its bitten-apple shape better, its south lobe will be brighter and more to the west. At low power, both lobes will widen irregularly, following the curves
to each side. The nebula, which has a good response to high magnification, reaches a size of 6 x 3.5 arcminutes, enlarging to 7 x 5 arcminutes by using an Oxigin III filter. With more than 170x, we will detect its extremely hot central star, a blue dwarf of 13.5 magnitude. This star is responsible for provoking the brightness of the nebular gas, with its UV radiation emission. Two faint overlapped stars will also start to be seen. By observing it with an 11”, its beauty will keep on surprising us, with a green-grey shade, irregular brightness, as if it were spotted, making the lobes and its thin side extensions stand out, appearing as a central rod crossing the nebula from north-east to south-west, and detecting about six or seven faint stars over it. When using an Oxigin III filter, it will get more contrast, appearing as turquoise-green, and the gas shell will vaguely expand to the east and west, almost completing its elliptical shape, with a gas of lower density, becoming a rugby ball.

In 1991, the amateur Czech astronomer Leos Ondra discovered a Mira-type variable star by matching photographs, with a magnitude varying from 14 to 18, situated at the north-west end of the nebula. He gave it the name of Goldilocks Variable.

We have travelled through some of the many objects in the border of Vulpecula-Sagitta, a rich area in which loads of open clusters, nebulae and asterisms may be found. We encourage you to keep on exploring the wonderful views of our exotic deep sky.-

End of podcast:

365 Days of Astronomy
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The 365 Days of Astronomy Podcast is produced by the Astrosphere New Media Association. Audio post-production by Preston Gibson. Bandwidth donated by libsyn.com and wizzard media. Web design by Clockwork Active Media Systems. You may reproduce and distribute this audio for non-commercial purposes. Please consider supporting the podcast with a few dollars (or Euros!). Visit us on the web at 365DaysOfAstronomy.org or email us at info@365DaysOfAstronomy.org. Until tomorrow…goodbye.

September 1st: International Observe the Moon Night!

kortney.hogan — Wed, 01 Sep 2010 11:00:13 +0000

Date: September 1, 2010

Title: International Observe the Moon Night!

Organization: NASA Lunar Science Institute (NLSI) – http://lunarscience.arc.nasa.gov/

Link: Observe the Moon Night – http://observethemoonnight.org/

Description: There’s nothing like gazing at the moon on a clear night, especially when you can share it with someone. Why not share it with the world? September 18, 2010 is International Observe the Moon Night. This is an annual event to engage the public and bring people together with amateur astronomers to raise awareness of the night sky and particularly the Moon, as well as spreading the word about NASA’s work in lunar research and exploration. Nancy Atkinson talks with some of the event’s organizers from the NASA Lunar Science Institute: Lora Bleacher, Doris Daou and Brian Day.

Bio: The NLSI brings together leading lunar scientists from around the world to further NASA lunar science and exploration.

Doris Daou is the Director for Education and Public Outreach for the NLSI. Lora Bleacher the Informal Education Lead for the Lunar Reconnaissance Orbiter mission, and Brian Day is Education and Public Outreach Lead for NASA’s Lunar Atmosphere and Dust Environment Explorer Mission (LADEE)..

Nancy Atkinson is a science journalist and is the Senior Editor for Universe Today.

Music: “Virginia Girls” by Ben Bedford, used by permission. http://benbedford.com/

Today’s sponsor: This episode of “365 Days of Astronomy” is sponsored by the NASA Lunar Science Institute at lunarscience.nasa.gov/, proud co-Founders of International Observe the Moon Night, around the globe on September 18th. More information at bit.ly/nomn

Transcript:

***Transcript coming soon.***

End of podcast:

August 31st: Apollo 11 Conspiracy

kortney.hogan — Tue, 31 Aug 2010 11:00:23 +0000

Date: August 31, 2010

Title: Apollo 11 Conspiracy

Podcaster: Thomas Hofstätter

Link: http://hidden-space.at.tf (The Hidden Space Project)

Description: After the first humans touched the lunar surface on July 20, 1969, many people did not believe in the achievement for all mankind. Several critics argued against the truth of Apollo 11 and the whole Apollo Program. In this podcast, I’m going to describe some major critics and their scientific explanation. If you have any questions, comments or suggestions to the podcast, feel free to write me an email to hidden-space (at) gmx (dot) at or visit me at my website at www.hidden-space.at.tf!

Bio: Born in 1993 near Vienna, Austria, Europe. Upper High School with focus on Computer Science.Interested in extreme small and extreme big, devious and uninvestigated things. My main aim is to bring astronomy to public and to establish secular interest in astronomy, physics and mathematics. Hoster of :: The Hidden Space Project :: at http://hidden-space.at.tf.

Today’s sponsor: This episode of “365 Days of Astronomy” is sponsored by From Mr. Thomas — Dedicated to my students: may they fly to work with jet-packs, and may some teach math to their students in their school on the moon. Welcome Back!

Transcript:

Welcome to this episode of 365 Days of Astronomy. My name is Thomas Hofst‰tter and I am the hoster of :: The Hidden Space Project :: at www.hidden-space.at.tf.

In this episode, I’m going to discuss the first lunar landing by Apollo 11 and some common critics. What’s the truth and what is just lie? I hope, you will enjoy it!

On July 16, 1969, Commander Neil Armstrong, Lunar Module Pilot Buzz Aldrin and Command Module Pilot Michael Collins lifted off to the first manned mission to land on the moon. They stayed in orbit for some hours and touched the lunar surface on July 20, 1969. Through his job as commander, Neil Armstrong was allowed to take the first step on the moon. During that, he said the perhaps most prominent words in human history: “That’s one small step for [a] man, one giant leap for mankind!”
That was the original mission sound from NASA.

Buzz Aldrin became the second to touch the lunar surface. Michael Collins had to stay in orbit in the Command and Service Module.

During their mission on the surface, Armstrong and Aldrin established several scientific experimental tools, which can be detected nowadays. Moreover, their footprints have been seen be the Lunar Reconnaissance Orbiter from NASA.

After their eight-day mission, the three astronauts finally watered near the US coast and were picked up by USS Hornet on which President Richard Nixon awaited them.

Soon after the successful mission, there were several voices raised, claiming that Apollo 11 had been a fake and no human had landed on the moon. Now, I will present and discuss a number of their arguments.

The first and most common argument against the existence of Apollo 11 was the waving flag that was photographed by the astronauts. According to critics reasoning that’s not possible due to the lack of atmosphere. Hence there can be no wind making the flag wave.

But exactly this lack of atmosphere is the reason for the waving. The astronauts had some problems positioning the flag in the right position because the lunar soil was harder than predicted. That caused the flag staff to vibrate for a longer time. In the earth’s atmosphere, the flag would not have waved so long because the atmosphere would have slowed down the vibration.

Another curious detail is, that at the lift-off of the first three missions on the moon, the flag fell down because it was placed too close to the lander.

Another argument for critics is the lack of stars. It’s a fact that there are no stars on the photographical and video material. Hence, critics say, the Apollo missions never can be landed on the moon, but the whole story was produced in the studio.

Also this argument can be disproved. The moon has a similar reflectance to coal. Moreover, there is not atmosphere. Which means that the unfiltered sunlight is reflected by the surface. That causes the surface to seem very light and therefore, the camera’s exposure time has to be set to a low level. The stars are more faint and therefore aren’t visible at the multimedia material.

Nevertheless, the Apollo astronauts were enrolled in schools how to use the stars as guidance. Fortunately, this method never had to been used in reality. That would have meant that the computer had failed to maneuver them through space.

That’s it for today. I hope, you enjoyed it. If you have any questions, comments or suggestions, write me an email to hidden-space (at) gmx (dot) at or visit me at my website at www.hidden-space.at.tf and observe basic questions of astronomy’s past and future as well as hidden and devious facts.

Thanks for listening and clear-skies!

End of podcast:

August 30th: Astronomy and the iPhone

kortney.hogan — Mon, 30 Aug 2010 11:00:34 +0000

Date: August 30, 2010

Title: Astronomy and the iPhone

Podcaster: TecnoCasters

Link: http://www.tecnocasters.com/

Description: The Tecnocasters discuss different astronomy apps for the iPhone.

Bio: TecnoCasters is the best technology podcast in Spanish. Hosted by Juan D. Guevara, Pedro Riveroll, Lorena Galan and Raul Mitre, TecnoCasters offers a funny and friendly point of view about the gadgets and technology you’ll come across in your ordinary day.

Produced simultaneously in the US and Mexico, TecnoCasters is an international podcast, specially created for the Spanish speaking audience in the world and or for all of those who want to improve their Spanish speaking skills and love technology at the same time.

Today’s sponsor: This episode of “365 Days of Astronomy” is sponsored by Kevin Marvel for June Anne Neaves Marvel.

Transcript:

Episode 365 Days Of Astronomy: Juan D. Guevara Torres

Hello everyone and welcome to this Episode of 365 days of Astronomy. My name is Juan Guevara Torres , Host of TecnoCasters – the best technology podcast En espanol. You can be in touch with us our website www.tecnocasters.com, via twitter twitter.com/tecnocasters

We are very happy and thrilled to be here with you all once again. We want to thank Nancy Atkinson, Senior Editor of Universe Today and Producer of Astronomy Cast for letting TecnoCasters be a part of such a cool project like the 365 Days of Astronomy.

Please check out www.365daysofastronomy.com for more information about this podcast and the many ways you can support this effort.

The last time the guest host for this podcast, I shared with you all the 5 top rated astronomy applications for your ipad. Since then, I got a lot of requests to do the same, but for the Iphone.

These days, it seems there is nothing you can’t do on an iPhone. Whether you want to use your phone as a GPS or just an education tool, you can do it all on iPhone. And thanks to the talented community of iPhone developers, you can now use your phone to navigate the skies right on your phone. Whether you want to know more about the stars or just want to find Pluto, it’s all possible on your phone.

So let me share with you all today, the 5 rated Astronomy Apps for your Iphone:

1) StarMap: StarMap is one of the best astronomy applications for iPhone. It can help you navigate the space and find new objects to observe fast. Hundreds of thousands of stars are available in its database.

2) Sky Gazer: Sky Gazer is designed for astronomy beginners, and it gets you familiar with the most important stars in the sky. And it uses iPhone 3GS’ compass feature to help you identify planets, stars, and more.

3) Distant Suns: Personal Universe: Distant Suns comes with thousands of stars and planets and helps you explore the sky right on your iPhone.

4) GoSkyWatch Planetarium: GoSkyWatch Planetarium is wonderful application that helps you locate and identify planets in the sky. If you are into astronomy, you are going to have a lot of fun with the star finder and other features available with this app.

5) Pocket Universe: Pocket Universe is another cool iPhone application that lets you navigate the stars and learn new things about this field. Great for beginners.

Well, that is all for us today. Be sure to check www.365dayofastronomy.org to keep up with this podcast!! And for those who love gadgets and technology and speak spanish dont forget so subscribe to the TecnoCasters – the best technology postcast en Espanol.

You can download our episodes in Itunes, at www.tecnocasters.com and also you can find TecnoCasters in your blackberry.

Don’t forget to follow me on twitter at www.twitter.com/guevarajd

My name is Juan Guevara Torres, host of TecnoCasters, and … thanks for listening!

Website:
www.tecnocasters.com

End of podcast:

August 29th: The Search for Intelligent Life

kortney.hogan — Sun, 29 Aug 2010 11:00:58 +0000

Date: August 29, 2010

Title: The Search for Intelligent Life

Podcaster: Marc West

Links: Mr. Science Show: http://www.mrscienceshow.com

Description: Marc West speaks to Dr Carol Oliver, a science communication researcher working for the Australian Centre for Astrobiology, whose key goals include contributing to the understanding of the origin of life on Earth and to set an Australian life-seeking instrument on the surface of Mars.

Bio: Marc West was a University Medallist in Chemistry at Sydney University, completed a Graduate Diploma in Science Communication at ANU and a Masters of Operations Research and Statistics at UNSW. Having grown up in Sydney, he ventured to Canberra and then London to be editor of Plus Magazine, and now works in Operations Research back in Sydney. Marc has written freelance for a number of magazines and newspapers, including G Magazine, The Canberra Times, The Helix and All Out Cricket Magazine, his article Political Music was published as one of top 50 science blogs of 2008 in The Open Laboratory 2008: The Best Science Writing on Blogs, whilst A sorry saga – the crumbling cookie made the 2009 version. Marc set up the Mr Science Show when on a trip to China, frequently talks on radio with The Diffusion Science Radio Show on 2SER, and co-founded The Beer Drinking Scientists podcast.

Today’s sponsor: This episode of “365 Days of Astronomy” is sponsored by David Rossetter on behalf of the Mid-Hudson Astronomical Association: A goofy group of geeks who love to observe and share the night sky around New York State’s Mid-Hudson region. [And my name is pronounced Ross' e ter' (that should be one of those upside-down e's in the middle).]

Transcript:

The search for intelligent life
Marc West speaks to Carol Oliver
www.mrscienceshow.com

Marc West: Greetings and welcome to the 365 days of astronomy podcast, my name is Marc West and this week we’re talking about the search for extraterrestrial life. I usually podcast as part of the Mr Science Show – www.mrscienceshow.com – and you’ve probably heard me before on the 365 days of astronomy podcast as one of the things I like to tackle on the podcast is astronomy.

Astrobiology is a fascinating and complex field of science. It is the study of the origin, evolution, distribution, and future of life in the universe, and is a relatively new field of science incorporating astronomy, biology, geology, palaeontology, physics, mathematics and other disciplines. It is even more fascinating given that we have never actually discovered life anywhere else in the universe!

Dr Carol Oliver is a science communication researcher working for the Australian Centre for Astrobiology, whose key goals include contributing to the understanding of the origin of life on Earth and to set an Australian life-seeking instrument on the surface of Mars.

I spoke to Carol about astrobiology and the SETI Project – the search for extraterrestrial life. The first question I asked here was “what is SETI all about?”

MUSIC

Carol Oliver: SETI uses the radio spectrum to look for signals from outer space that may hint at intelligence out there in our galaxy – it is limited to our galaxy because of the fact that space is very large – across our galaxy is 100 thousand light years – that’s the time it takes light to travel from one end of the galaxy to the other, which is around about 300 thousand kilometres per second for 100 thousand years, so its very large. And our galaxy is one of maybe another 100 billion galaxies in the Universe. So there’s an awful lot of space out there. It would be unusual if we were the only other life out there in the Universe – but we might be, we just don’t know the answer to that question, and that’s what SETI is about.

MW: Cause looking for intelligent life I guess is different to looking for just ordinary life. The electromagnetic spectrum is infinitely big – where do you look?

CO: Oh well, that’s very easy. It happens there’s a space in the radio spectrum where noise fro the rest of the Universe drops to the minimum level, and its between two molecules – the H line and the OH line. And you put those two together you get water – so its called the water hole. And its assumed we would actually find a message from extraterrestrial intelligence at that point because it would be the same for everyone in the Universe. If you’re going to transmit, you’re going to transmit at the quietest part of the spectrum.

But even then, there are billions of frequencies we could be looking for. Really SETI is a 9 dimensional search. It’s three times in space – up down and across. Time frequency, polarization – there’s two of those – modulation and transmitted power – it truly is looking for a needle in a haystack.

We really can’t rely on a directed message to Earth – which we are at the moment. But if you can imagine that in the last 70 years we have been transmitting television and radio signals – they just leak naturally into space. If we could detect those, then we may be able to detect intelligence elsewhere in the Universe.

MW: Presumably it would be a fairly big media event if we found some ET life – so we haven’t found any yet. But in 1977 they had the WOW signal. What was that about?

CO: Well that was at a telescope no longer in existence, and it was when they used to have ream of paper to deliver what was coming through the collection system. The operator came in one morning and looked at the numbers on these charts and they were way off the scale. They could only be a very narrow band signal from very far away. The operator circled those numbers and wrote “Wow” – hence the name the “Wow Signal”

In spite of many years of searching that part of the spectrum, it has never been found again. So for SETI purposes, we don’t regard it as a SETI signal as we need proof. We need for others to be able to go alone and look at that part of the spectrum and detect this narrow band signal them.

So although SETI has occasionally found a signal repeated twice, its not continuous and there could be other explanations. SETI is a scientific search for ET intelligence in the Universe, so it has a very high bar to then announce that they’ve actually found a signal.

MW: Where on Earth is SETI based? Its based all over the Earth I guess.

CO: Yes! The most strategic and biggest organisation is the SETI Institute in California – they sit just outside the gates of NASA AMES and most of their employees actually work at NASA in aspects of astrobiology, which is looking forward life elsewhere in the Universe, but not necessarily intelligent. They use the largest telescopes on Earth at Arecibo in Puerto Rico and also the Parkes Radio Telescope here in New South Wales. And they’ve also got the Allen Telescope Array. Now that’s in Hat Creek in California. They want 350 small 6-meter dishes there. They’ve currently got 42. Those have cost $50 million to date. But they’re doing SETI in concert with normal radio astronomy so those dishes have a double use, and also in off time the US Air Force uses it for tracking Satellite debris. So they’re hoping to increase that number of dishes, but they are the only dedicated search in the world.

There are other smaller projects in the world. There are none currently in the southern hemisphere, which is a shame because in the southern hemisphere we look right into the heart of the galaxy, which means we have the best real estate in the world. And all the others are in the northern hemisphere – but that’s what we’re stuck with.

MW: And you can participate in SETI at home on the Internet?

CO: You can! And that’s been going since about 1995 and basically it’s collecting all the data that has ever been collected by SETI, by the SERENDIP group at UC Berkeley. Real parcels of data are sent out to your CPU when you’re not using it, and it analysis it and sends it back. If you discovered a signal then you’d be on the paper. To date since 1995 they haven’t found anything – there have been a couple of interesting episodes, but they haven’t found anything. The interesting thing about SETI at home is that that technology has been employed for other things, for example cancer research.

MUSIC

MW: Well that’s all the time we have in today’s episode of the 365 days of astronomy podcast. My name is Marc West and I was speaking to Dr Carol Oliver. If you’d like any more information and a slightly longer version of this podcast, get over to my website at www.mrscienceshow.com. Thanks for tuning in, I’ll hopefully catch you soon on this podcast, and I’m sure the 365 days of astronomy podcast will catch you tomorrow.

End of podcast:

August 28th: An Introduction to Space Exploration

kortney.hogan — Sat, 28 Aug 2010 11:00:15 +0000

Date: August 28, 2010

Title: An Introduction to Space Exploration

Podcaster: Gordon Houston

Organization: JPL/NASA Solar System Ambassadors Program – http://www2.jpl.nasa.gov/ambassador/

Description: Space exploration is one of the most challenging human endeavors ever undertaken. However, most of us have a limited working knowledge of space exploration, the methods used, and the unique language we hear used by mission controllers. Have you ever wondered what all those terms mean when the Space Shuttle or other exploration missions take off, such as downlink, payload, flybys, gravitational assist, and so on? In this podcast, I will give a brief history of space exploration, explain the process in broad terms, and finally try and define some of the language and terms used during the missions.

Bio: A lifelong observer, Gordon L. Houston holds a Master of Science in Astronomy from Swinburne University and the designation of “Master Observer” through the Astronomical League, completing 10 observing programs. Gordon is a member of the Houston Astronomical Society, The Association for Lunar and Planetary Observers, Astronomical Society of the Pacific, and a George Observatory volunteer, where he is a certified operator of the 36” Gueymard Research Telescope. Gordon teaches an astronomy course at the Blinn College, Schulenberg, Texas campus and is director of the Schaefer Observatory. Finally, he is a Solar System Ambassador for NASA’s Jet Propulsion Laboratory in Pasadena California.

Today’s sponsor: This episode of “365 Days of Astronomy” is sponsored by — no one. We still need sponsors for many days in 2010, so please consider sponsoring a day or two. Just click on the “Donate” button on the lower left side of this webpage, or contact us at signup@365daysofastronomy.org.

Transcript:

AN INTRODUCTION TO SPACE EXPLORATION
Podcast by Gordon L. Houston, August 28, 2010

Hello and welcome to another edition of the 365 Days of Astronomy podcasts. I am Gordon Houston, Solar System Ambassador for NASA’s Jet Propulsion Laboratory.

Space exploration is one of the most challenging human endeavors ever undertaken. Many of us are interested in space, but most of us have a limited working knowledge of space exploration, the methods used, and the unique language we hear used by mission controllers. In this podcast, I hope to give a brief history of space exploration, explain the process in broad terms, and finally try and define some of the language used during the missions such as downlink, payload, flybys, gravitational assist, and so on.

There are multiple reasons for exploration of the planets. Solar system formation and search for life through astrobiology, are two of the main objectives for any space science mission. The exploration of the solar system began almost immediately upon man’s first entry into space, with the Russian satellite Sputnik in 1957. Just two years later in 1959 the Russians were successful in sending Luna 1 on the first ever flyby of the Moon. That same year, NASA established a long-range plan of space exploration, with the inner solar system as the primarily target of early exploration, as they are the closest targets. So, the Moon, Mars, and Venus have had the most exploratory missions to date.

The outer solar system, consisting of the gas giants Jupiter, Saturn, Uranus & Neptune, has had much less exploration activity. Voyager 2 is the only mission to have had close flyby contact with both Uranus and Neptune in 1986 and 1989 respectively. Jupiter and Saturn have had recent mission contact, including Galileo to Jupiter and a currently active mission, Cassini is investigating the Saturn system. The New Horizons mission is currently in route to Pluto and the Kuiper Belt.

Space exploration has expanded beyond planetary exploration missions. The list of targets to investigate include comets, asteroids, Kuiper Belt objects, and the Sun. Examples of some of these missions are the STARDUST mission, which explored the comet Wild-2, and has an extended mission life, now known as STARDUST-NExT which is exploring the comet Tempel 1. The DAWN mission is preparing to explore the asteroid Vesta. There are so many missions, I encourage you to visit the Jet Propulsion Laboratory’s website, Missions page, http://www.jpl.nasa.gov/missions/index.cfm.

The science objectives of any mission are the very starting point for any mission proposal. Space exploration can include human participation, but robotic spacecraft with various scientific instrument packages have been the primary exploration method. Mission budgetary issues are always a major consideration. The methods of exploration can be by either remote sensing or in situ measurements or both. The type of investigation will influence the instrument package, spacecraft design, and the cost. Remember, exploration of any planet is a multi-mission process.

The two methods of exploration, remote sensing and in situ, are primarily related to use of robotic instruments. Man has used remote sensing since they first observed the stars and as such, the use of telescopes is a remote sensing technique. A more constrained definition of remote sensing is “Remote Sensing involves gathering data and information about the physical “world” by detecting and measuring signals composed of radiation, particles, and fields emanating from objects located beyond the immediate vicinity of the sensor device(s).”

In Situ exploration literally means “in place” or in touch with the medium being explored or measured. So, a simple definition of in situ exploration would be to change the last part of definition of remote sensing to “…..from objects in contact with the sensor devise(s).” An example is the magnetometer on the Cassini mission. It measures Saturn’s magnetic field, with the spacecraft literally inside of, or in touch with the magnetic field.

Space exploration is guided by what is known as Space Mission Architecture. It is generally divided into five main areas. We have already discussed the first main area, the space mission itself, which is defined by the science objectives. It impacts all other facets of the space mission architecture. These four main areas are: 1) The spacecraft, 2) trajectories and orbits, 3) launch vehicles, and 4) the missions operations systems.

The science objectives directly influence the design of the spacecraft. There are two main parts to the spacecraft, which are the “bus” and the “payload.” The “bus” is the skeleton that holds everything together and it provides all the functions, which support the operation of the payload, including electrical power, temperature control, data storage, communications, and spacecraft orientation. Spacecraft orientation is important, to ensure that the instruments are pointing in the right direction to take the science measurements. The “payload” is the part of the spacecraft that performs the exploration, which is the compliment of instruments measuring and interacting with the “subject” defined by the mission science objectives.

Examples of many of these instruments include visual cameras, both narrow and wide field, all types of spectrometers, magnetometers, radar equipment, microwave, particle detectors, and others. It is common for these instruments to be designed for a specific mission and environment. A name is created for these instruments based on the type or purpose from mission to mission, making it somewhat confusing. For example, the Composite Infrared Spectrometer on the Cassini mission is referred to in capital letters as CIRS. Just remember, each instrument reduced to its common denominator is still just a spectrometer or magnetometer, regardless of the specialized application or name.

The next area of mission architecture, trajectories and orbits, is guided by the mission science objectives, the spacecraft, and the payload. We have talked about two broad areas of the method of exploration. It is necessary at this point to point out some of the different techniques used in space exploration. A mission may be designed as a single flyby, an orbiter with multiple flybys or swingbys, and lander. A mission that does a flyby of a target subject is one style of exploration and the least expensive, but you get one opportunity to get the science measurements. An example would be the Voyager missions, which did flybys of the outer planets, with Voyager 2 specifically visiting Uranus and Neptune. Both of these missions have basically reached the edge of the Solar System.

An orbiter mission has the capability of many flybys, usually called swingbys, which provide multiple opportunities for science measurements. Orbiter missions can also launch specialized probes into the subject or send landers that are or become rovers or penetrators. These different methods of delivering science instruments increase the cost of the missions, which is an important concern for any mission. Examples of rovers are the Mars rovers known as Spirit and Opportunity, both of which had exceptionally long mission lives. The new Mars Science Laboratory has a new rover called Curiosity, with a 2011 expected launch date.

The launch vehicles are the method of lifting the spacecraft out of the Earth’s gravity field. Then considerations must be taken for the location of the target or subject of the mission. The mass of the spacecraft and the mass of the launch vehicle and the propellant are the controlling factors as to the size of the launch vehicle. Launch vehicles come in different configurations and depending on the mass, have multiple stages, to ensure a lift off and initial ∆V, which is the change in velocity.

Having enough propellant and enough thrust to propel a spacecraft has been a limiting factor to space exploration. The Cassini mission, which was a 6,000-kilogram spacecraft, was launched by the most powerful rocket available to NASA in 1997, yet this was not enough to propel it to Saturn. The invention of the gravity-assist trajectory enabled the possibility of interplanetary space travel, which is a technique whereby a spacecraft takes angular momentum from a planet’s solar orbit to accelerate or decelerate the spacecraft. Gravity assist was used by Cassini to get to Saturn, but also uses it to help guide the spacecraft to encounter multiple targets such as flybys of different moons of Saturn.

The term “launch window” is a familiar term, which is a direct result of the mass of the spacecraft and the launch vehicle. All the planets are orbiting the Sun and thus in motion relative to the Earth. The launch window is the particular time to launch on a particular day to ensure that the energy produced by the launch vehicle meets or exceeds the energy requirement to get the particular spacecraft to the particular target body. This target body can be an orbiting planet such as Venus, which can be used for a gravity assist. Thus, Venus needs to be in the right location when the spacecraft arrives to perform the gravity assist.

Finally, the last part of the mission architecture is the mission operations. There are teams for controlling the spacecraft from lift off to target. They monitor the health of the spacecraft and communicate commands. The communication terms of downlink and uplink are often heard. Uplink is a command to the spacecraft and downlink is a communication from the spacecraft down to Earth. The science teams monitor and control the craft during the engagement of the target body or subject, including the monitoring of the science data sent. All communications, including commands and data are facilitated by the Deep Space Network or DSN for short. The DSN is a series of three radio dishes spaced 120 degrees apart around the Earth’s globe, in California, Spain, and Australia. This permit constant observation and contact with the mission.

So, I hope of have not been too technical and have provided you with a basic understanding of space exploration. I have only provided a glimpse of whole process involved, but you can probably determine that many teams are necessary to ensure the success of one mission. I encourage you to look further into this fascinating topic.

Finally, I want to say Happy Birthday to my mother, who turns 83 today. This is Gordon Houston, JPL Solar System Ambassador, signing off, Ad Astra, “To the Stars.”

End of podcast:

August 27th: From Galileo to Pluto’s Demotion- Two Good Reads for the End of Summer

kortney.hogan — Fri, 27 Aug 2010 11:00:06 +0000

Date: August 27, 2010

Title: From Galileo to Pluto’s Demotion- Two Good Reads for the End of Summer

Podcaster: Sue Ann Heatherly

Organization: NRAO: http://www.gb.nrao.edu/

Description: Dr. Larry Marschall coauthored, along with Stephen Maran, two fascinating books last year, one called Galileo’s New Universe, and the other Pluto Confidential. Can you guess what they are about? Learn more about them and listen in to find out what Larry learned in writing these books.

Bio: Sue Ann Heatherly is the Education Officer at the NRAO Green Bank WV site. She comes to astronomy by way of biology (BA in 1981), and science education (MA in 1985) She visited the Observatory as a teacher in 1987 and knew she’d found Camelot. She has been employed with the NRAO since 1989.

Today’s sponsor: Ron Heiby is happy to sponsor today’s “365 Days of Astronomy” podcast in honor of his wife, Beth, on the occasion of their 27th anniversary.

Transcript:

***Transcript coming soon.***

End of podcast:

August 26th: The Search for Extraterrestrial Life – Vox Pops

kortney.hogan — Thu, 26 Aug 2010 11:00:30 +0000

Date: August 26, 2010

Title: The Search for Extraterrestrial Life – Vox Pops

Podcaster: Marc West

Link: http://www.mrscienceshow.com

Description: Opinions of the people of Surry Hills in Australia on the search for extraterrestrial life.

Transcript:

The Search for Extraterrestrial Life – Vox Pops

INTRO:

Marc West: Greetings and welcome to the 365 days of astronomy podcast. My name is Marc West, and you may have heard me before on this podcast, or you’ve perhaps heard me on the Mr Science Show, the podcast where science meets pop culture www.mrscienceshow.com. How, like a number of scientists, I like to ponder science over a beer. I occasionally put out a podcast with a mate of mine Darren Osborne, called the Beer Drinking Scientists. You can find that at www.beerdrinkingscientists.com. In these shows we get out to the pub, have a beer, chat about a relevant scientific topic and also then have a chat to the people in the pub about the scientific topic of the day.

In this episode of the 365 days of astronomy podcast, I’m bring to you the opinions of the people of Surry Hills on the search for extraterrestrial life. Here’s what they had to say.

Darren Osborne: So I was just wondering, do you think that there’s life out there?

Guest 1: Absolutely, I’ve seen a UFO, and a lot of people never believed me, I’ve only told a few people and they think I’m crazy, but yeah I saw a UFO one night and it freaked the hell out of me!

DO: So where did you encounter this UFO and can you tell us a bit about it?

G1: I was living not far from Blacktown, I was doing my HSC and I lived around the corner from this big lookout, so I went and had a cigarette break from studying, and all of a sudden all the lights went out in town and things got really freaky. I looked up in the sky and there was this huge flying saucer with lights going around the circumference, like you see in the movies, it was outrageous. And of course I was a little bit panicky – started running home, around the corner and the UFO was flying thru the air. And where I lived we had a flat above the garage, so I sat out on the steps for about 10 minutes, and this is where you’re gonna think I’m really nuts, it spat out a baby ship! And I only wished I had a camera on the night. The ship looked like it was flying towards to house – God knows how far away it was. Anyway, I went to bed that night, the radio wasn’t working properly, the TV was flickering, the lights weren’t working and I hid under the covers. I actually wrote a letter to my mother saying if I’m not here in the morning I’ve been abducted by aliens! I really thought I was a goner!

Anyway I woke up, I was all right, nothing happened, there were no little green men in my flat – there you go, true story!

DO: You mentioned people don’t believe you, how do they react when you tell them the story?

G1: Oh they ask me if I was on drugs – but I didn’t even know what a lot of stuff was back then – I was pretty innocent as far as that stuff goes! So totally sober, black coffee, cigarettes, that was it. People just think I was making it up or having a joke with them, but no, dead-set true. I don’t know if anyone else saw anything that night – but if they looked up in the sky that night, they couldn’t have missed it! HAHA

Marc West: So you’re firmly in the “yes category” to is there alien life out there?

G1: Abso-bloody-lutely! May the force be with you!

BREAK

G2: Yeah I don’t know if there is alien life out there, but you’d like to hope we’re not the smartest creatures in the Universe cause we don’t seem to be doing a very good job of managing our own planet. So hopefully someone else can do a better job.

DO: Do you believe we’ve been visited, do you believe in the idea of UFOs and aliens that have come to visit Planet Earth?

G2: Pooh, I believe that there are too many things that have happened on Earth, like, people cant determine how ancient civilisations constructed things the way they did, pyramids, ah, the Incas, so yeah, I think so.

MW: You don’t think the world is going to end in 2012 then, like the Incas did?

G2: I saw that movie a couple of weeks ago, and um, yeah it didn’t look promising, so yeah, I hope not cause Ill still be alive then!

MW: Well it wasn’t a documentary, I don’t think…

G2: Yeah, well let’s hope not.

BREAK

DO: So do you believe that there’s like beyond Earth?

G3: Yeah I probably think that there must be something else existing, but I don’t know what kind of form, or how intelligent, or how active they are in the whole solar system.

DO: What about UFOs, are we being visited – do you think that’s all made up or is there a chance we could be being visited?

G3: I think a lot of people would like to believe that, so that’s enough for them but I’m not really positive.

MW: So you’ve never seen a UFO yourself?

G3: No, not yet, there’s time.

BREAK

DO: Do you believe in UFOs and alien life?

G4: Err, I’ve never really thought about it, but I guess… well where did we come from, there has to be something else out there before us, and I reckon after also, so I’m sure there would be something there.

G5: If you look into the sky, and you see a star its generally a Sun, um… which will have a galaxy around it, and we’re too small – we cant even fathom how big the universe is and yeah, there’s definitely life out there.

DO: What about the idea of UFOs, that UFOs with aliens have come and visited us, do you support that idea?

G5: Err, possibly… Are we an experiment? Was Jesus an alien?

MW: I hadn’t thought of that idea before….

DO: There are some who are critical of the search for extra-terrestrial life, whether it be radio telescopes listening out for aliens, or sending spacecraft out to Mars to search for life, is it a waste of time or should we continue to do it?

G5: Well it’s out there, you gotta have a look!

BREAK

MW: Well that’s all we have time for in today’s edition of the 365 days of astronomy podcast. Have you seen an alien? Do you think Jesus Christ was an alien? Let us know on the website – www.365daysofastronomy.org – My name’s Marc West and to find out more about me, my website’s www.mrscienceshow.com. I’d love to see you over there if you have any comments, questions or queries. Over there, and at www.beerdrinkingscientists.com you’ll find the full Beer Drinking Scientists episode on the search for extraterrestrial life. Thanks very much for joining me, my name’s Marc West, Ill catch you, hopefully soon, on the 365 days of astronomy podcast.

End of podcast:

August 25th: Can I Look Through Your Telescope?

kortney.hogan — Wed, 25 Aug 2010 11:00:09 +0000

Date: August 25, 2010

Title: Can I Look Through Your Telescope?

Podcaster: Rob Berthiaume

Links: www.yorkobservatory.com
www.youdontfreezeinspace.com

Description: Its a lot of fun to look through telescopes, and even more fun to share and let other people look. But what should you show them? How should you do it? This podcast gives a few ideas and tips.

Bio: Robert Berthiaume is working towards an MSc in atomic physics at York University in Toronto, Canada. When he can get away from making measurements of local gravitational acceleration, he rides his motorcycle when the sun is up, and shares the stars with the public at the observatory when it’s not.

Today’s sponsor: This episode of “365 Days of Astronomy” is sponsored by Toronto Centre of the Royal Astronomical Society of Canada.

Transcript:

Hi there. I’m Robert Berthiaume bringing you the August 25th edition of the 365 Days of Astronomy Podcast from the York University Observatory in Toronto, Canada. Today I’ll be sharing a few thoughts on how to share the heavens with people when you’re out with your telescope. I’ll start with a disclaimer that these tips may not be applicable to all people nor all the time, but I’ve found that they generally hold true.

There are very few people in this world who won’t be interested in looking at a planet or star or galaxy through a telescope. But there are also very few people in this world who have long attention spans and lots of patience. This means that viewing experiences have to be done, not necessarily quick, but definitely in an expeditious manner. No one wants to be waiting around while you find the next object, and lets face it, at that moment you’re there to show off the stars, not to be searching or tinkering. Try to minimize the time people might have to stand around; this includes making sure you already have a short list of objects in your head to show off, being familiar with their locations, having your finderscope or laser pointer well aligned. People will kick your tripod and you will have to re-center the object, being prepared will minimize the time people are standing around.

Speaking of attention spans, I find it’s better to keep descriptions and commentary shorter rather than longer. I personally have great difficulty with this; I can easily drone on and on about whatever we’re looking at, but pretty soon the eyes glaze over, people stop paying attention, and everybody is lost in what you’re saying, and not in the good way. What I try to do more and more now, is after every couple of sentences, I’ll do a “boredom/understanding check” of my audience. If it looks like people get what I’m saying and are into it, then I might continue, if not, I’ll ask if there are other questions and qrap up the topic. There’s no real harm in saying too little, if people want to hear more, they’ll very likely ask that you tell them more.

When people do ask questions, you’ll quickly start to see that most of the questions fall into one or more of three categories:

1. Numbers questions: “How many stars are in the galaxy we’re looking at? “

2. Current events/happenings.: “I heard scientists discovered gamma rays coming from 4 billion light years ago. Are we going to die?”

3. Exotic and popular topics: This includes, but is not limited to, anything having to do with black holes, the moon landings, 2012, the Sun exploding, the Mars-will-be-as-big-as-the-moon-and-brighter-than-the-Sun-this-August or whatever e-mail, and the new favourite since 2006, Pluto not being a planet anymore.

There will be other questions, but you’ll satisfy most of your inquisitors if you do three corresponding things. Know a few characteristic numbers about objects you show to people, like how far away they are, how old they are, how big they are, etc. Try to follow space-related news at least enough to be aware of any significant space missions, meteor showers, or new discoveries. And read a little about the popular topics and misconceptions in astronomy that will come up over and over again.

Another important thing to realize when you’re commondereing your telescope with an audience, is that while you’re the expert at that time, you’re not an encyclopedia. Repeat after me: “I don’t know, but I can find out for you”. “I don’t know, but I can find out for you”. Feel free to use this phrase whenever you are faced with a question that you’re really not sure of. People will not lose your respect, and you won’t at all look stupid. There are enough misconceptions about astronomy that filter through the public, it’s best to not introduce any new ones. And if you do actually follow up later on, you’ll be forced to do a little research, and not only will you uphold your promise of answering the question, but you’ll learn your new thing for the day while you’re at it.

So those are a few tips for preparations and explanations, but what about actually looking at stuff? What kinds of things are people going to have fun looking at?

Well if you know your audience, or maybe you have a few strangers that aren’t shy, they may be able to figure that out for you. Always always ask for requests. People are going to have the most fun and be most interested in seeing things they already know something about. Maybe they have a favourite planet that you can show them. Maybe years ago they did a project on the Andromeda Galaxy and they’d like to see it for themselves. And of course, as much as us astronomers despise the confusion between our science and the other similarly-named pseudo-science, astrology does create opportunities to connect personally with people and pass along to them some real, factual, non-coincidental information about the stars above.

Using zodiac constellations as a launching point is not only personal, but it is very relatable as well. I find it useful to use three “R’s” to pick things to show off and describe. I try to make sure the objects are easy to relate to, recognize and remember. Show them the coathanger cluster or the teapot in Saggitarius, or colourful doubles. People have a lot of fun with with shapes and colours and the like, and they’ll be much more likely to recognize the constellation later or remember exactly what they looked at when they tell their friends about the evening at their next dinner party.

People like stories. That’s why bookstores and movie studios will always be in business. If you’re looking for a short lineup of objects to showcase, but don’t know where to start, think about telling a story. Take people on a trip through the life of a star by looking at a nebula, then a star, then a planetary nebula or supernova remnant. Or take them on a trip through space starting with our closest neighbor, the moon, then off to a planet, then a star, and finally off into intergalactic space. You can always tell a story about the different kinds of objects that are out there, animating your narrative with views of a planet, a star, a galaxy, a cluster, etc.

You’ll read an audience pretty quickly. Sometimes, most of the time, you’ll want to show off the best and brightest we have to offer: the Moon, Saturn, Jupiter. These things all require little imagination and are always satisfying. But sometimes you’ll get someone who wants to use their imagination, so don’t be afraid to show them a star with a known exoplanet or a faint, far-off galaxy. While most people may say “that’s it?”, remember there are a few out there that will respond “wow! I can’t believe what I’m looking at!”

It doesn’t hurt to work under the assumption that the people stopping to look through the eyepiece are interested, but that they’re on their way to somewhere else they need to be and that they aren’t dressed for the weather. If they take a peek, and say “neat” and then walk off hurriedly, don’t take it personally, they just have different priorities than us astronomers. And that’s OK. Nobody’s perfect.

One short note about younger audiences: They have shorter attention spans, earlier bedtimes, higher expectations, and so on. So everything I’ve said in this podcast, emphasize 10x when you’re intereacting with kids.

The last thing I suggest, and implore you do any time you’re in any capacity to educate people about astronomy, whether you have a telescope or not, is to explain, discredit, and quash the annual August Mars e-mail. It seems like that e-mail will live on forever, but, call me crazy, I have hope that if enough of us spend enough time, we can kill it.

Now I’ve only been doing this for not even a decade, and I’m sure there are other ideas and tips that many of you more experienced observers have. If you’d like to share, please do, my e-mail is rjb@yorku.ca . I hope everyone listening can take something away from this podcast, and maybe had a little fun. Thanks for listening; until next time, this is Robert Berthiaume wishing you all clear skies and good times.

End of podcast:

August 24th: Peering Into the Future- The Decadal Survey

kortney.hogan — Tue, 24 Aug 2010 11:00:07 +0000

Date: August 24, 2010

Title: Peering Into the Future- The Decadal Survey

Podcaster: Mike Simonsen

Organization: http://www.aavso.org/
http://simostronomy.blogspot.com/
http://www.slackerastronomy.org/wordpress/

Description: Every ten years since the 1960’s, astronomers have formed expert panels and committees who coordinate a gigantic undertaking called the Decadal Survey of Astronomy and Astrophysics. Its mission is to survey the field of space and ground-based astronomy and astrophysics, then produce a report recommending priorities for the most important scientific and technical activities for the next decade. The results of the latest Decadal Survey, a massive summary report entitled New Worlds, New Horizons in Astronomy and Astrophysics, has been in the works for nearly two years, and was just released August 13th.

Bio: Mike Simonsen is one of the world’s leading variable star observers. He works for the American Association of Variable Star Observers as Development Director and heads the organization’s Cataclysmic Variable Section, Chart Team and Mentor Program. He writes the astronomy and variable star blog, Simostronomy and is a cast member of the Slacker Astronomy podcast.

Transcript:

Hi, I’m Mike Simonsen.
Today I’d like to tell you about the way astronomers plan for the future.

Astronomers are constantly looking into the past. No matter where you look out into space you are seeing things as they were minutes, hours or millions of years ago. Even at 186,000 miles per second, it takes eight minutes for light to reach us from the Sun. It takes four and a half years for light to reach us from the next nearest star, and millions or billions of years to reach us from other galaxies. So astronomers spend a great deal of time looking into the past.

But astronomers also have to look forward, and make predictions about the future. In order to keep astronomical research pushing at the forefront of our knowledge, astronomers need to predict what new areas of research and technology will help answer the pressing science questions of the next decade, and how much it will cost to build the telescopes, spacecraft and experiments needed to unlock the secrets of our Universe. And since it is impossible to pay for everything, someone has to prioritize which projects will get the biggest bang for the bucks in the coming decade.

So every ten years since the 1960’s, astronomers have formed expert panels and committees who coordinate a gigantic undertaking called the Decadal Survey of Astronomy and Astrophysics. Its mission is to survey the field of space and ground-based astronomy and astrophysics, then produce a report recommending priorities for the most important scientific and technical activities for the next decade. The results of the latest Decadal Survey, a massive summary report entitled New Worlds, New Horizons in Astronomy and Astrophysics, has been in the works for nearly two years, and was just released August 13th.

The three key science objectives for the coming decade are laid out in this report. The first is Searching for the First Stars, Galaxies, and Black Holes.

We’ve learned a lot about the history of the universe, from the big bang to the present day. But a great mystery now confronts us: When and how did the first stars and galaxies form out of cold clumps of hydrogen gas and start to shine? When was our “cosmic dawn”?

Observations and calculations suggest that this phenomenon occurred when the universe was roughly half a billion years old. Scientists think that the first stars were massive and short- lived. They quickly exploded as supernovas, creating and dispersing the first elements heavier than hydrogen, helium, and lithium, and leaving behind the first black holes.

After the cosmic dawn, more and more galaxies formed, merged, and evolved as their gases turned into stars and those stars aged. Many of the faintest images from current telescopes are of these infant hungry galaxies. We now know that these cannibalistic galaxies quickly grow black holes in their nuclei with masses that can exceed a billion times the mass of the Sun and they turn into extraordinarily luminous quasars. How this happens is still a mystery.

We also know that the giant galaxies we see around us today were built up from the mergers of smaller galaxies and the accretion of cold gas. Not only do the stars and gas commingle, but the central black holes also merge. We should be able to detect waves in the fabric of space-time— gravitational waves—that result from these dramatic mergers.

Exploring the first stars, galaxies, and quasars is a tremendous challenge, but our ability to look back in time to the beginnings of our Universe improves every year. Astronomers are now looking forward to the time when we can look backward as far as there is anything to see!

The second key science objective is Seeking Nearby, Habitable Planets.

Remarkable discoveries over the past 15 years have led us to the point that we can hope to answer the question, “Can we find another planet like Earth orbiting a nearby star?”

In 1995, a star just like the Sun in the constellation Pegasus was shown to vary regularly in its radial velocity, resulting from the gravitational pull of an orbiting planet. This planet was determined to be roughly as massive as Jupiter but orbited its star every 4 days, far more quickly than any of our Sun’s planets.

So, with a single set of observations we answered an age-old question: yes, there are other planetary systems around stars like our Sun. However, they do not necessarily look like our solar system. Today we know of almost 500 extrasolar planets with masses ranging from a few Earth masses to a few thousand times the mass of Earth. Their orbits, composition and other characteristics continue to surprise us as we learn more about these other worlds.

Radial velocity detection of planets is much more sensitive, reaching down below 10 Earth masses. We can detect tiny changes in the light output of a star as a planet transits in front of it from our perspective here on earth, a technique currently being used by the Kepler space telescope. We can also probe planetary systems by measuring microlensing as their gravitational fields bend rays of light from a more distant star.

Telescopes on the ground and in space have even directly imaged a few large planets as distinct point sources. In other cases, we can learn about planetary systems by measuring infrared and radio emission from giant disks of gas out of which planets are believed to form.

Even more important to identifying Earth-like worlds, the Hubble Space Telescope and the Spitzer Space Telescope have found the spectral lines of carbon dioxide, water, and the first organic molecule, methane, in the atmospheres of orbiting planets. All this in fifteen years is extraordinary progress.

Astronomers are now ready for the next stage in the quest for life beyond the solar system; to search for nearby, habitable, terrestrial planets with liquid water and oxygen. The host star of such a planet may be one like our Sun, or it could be one of the more plentiful but less hospitable cooler red stars.

Cooler red stars are attractive targets for planet searches because light from a planet will be more easily detected above the dimmer light of these cool stars. However, terrestrial planets are relatively small and dim, and are easily lost in the scattered light created by the dusty disks that typically orbit stars.

Armed with new technologies and advances in understanding of the architectures of nearby planetary systems, astronomers hope to meet this challenge in the coming decade also.

The third key science objective for the coming decade deals with the physics of the Universe and is entitled Understanding Scientific Principles.

Astronomy and physics are closely related. For example, observations of orbiting planets furnished verifications of Newton’s law of gravitation and Einstein’s theory of general relativity. The universe is the only laboratory that offers access to special conditions and circumstances not available on Earth, helping us to both understand and discover new elements of the basic laws of nature.

In this past decade we have witnessed the confirmation of the remarkable discovery that the expansion of the universe is accelerating. This acceleration is attributed to the effect of a mysterious substance called dark energy that accounts for 75 percent of the mass-energy of the universe today. The remainder of the mass-energy is comprised of 20 percent dark matter, which is believed to comprise new types of elementary particles not yet found in laboratories on Earth and 4.6 percent regular matter, the stuff we can see and feel directly.

Through our observation of the Universe we have recently learned a very important fundamental fact about the expansion of the universe and the fact that 95 percent of the Universe is beyond our ability to detect! We can only infer the properties of dark energy by measuring its effects on the expansion rate and the growth of structure in the Universe at large.

In the coming decade we hope to answer questions about the state of the universe at a time very soon after the big bang. Recent observations of the cosmic microwave background are consistent with the theory that the universe underwent a burst of inflation when the expansion also accelerated and the scale of the universe grew from its infinitesimally small beginnings to about the size of a person.

Gravitational waves created at this time carry information about the behavior of gravity and other forces during the first moments after the big bang. These waves can be detected through the distinctive polarization pattern that they impose on the cosmic microwave background radiation. Detection of this imprint would help us explore fundamental physics at very high energies and reveal new details about the birth of the universe.

Another opportunity to study fundamental principles in physics comes from precisely observing the behavior of black holes. Black holes are commonly found in the nuclei of galaxies and are born when very massive stars end their stellar lives. Scientists have an exact theoretical description of space-time around black holes but do not know if this description is correct. One way to find out is to observe X-ray-emitting gas and stars as they spiral toward a black hole’s event horizon, a place beyond which nothing, not even light, can escape. Another is to observe the jets that escape black holes with speeds close to that of light.

However, the best test of all will come from measuring the gravitational radiation that is observed when moderate-mass black holes merge. We now have the software and the computing power to calculate the signals that should be seen and the technology to test the theory.

The experiments and tools proposed to investigate these key scientific questions are as remarkable as the questions themselves. Satellites that fly in formation to detect gravity waves in space, a space-born Wide-Field Infrared Survey Telescope designed to explore the acceleration of the expansion of the Universe and hunt for earth-like planets, and the Large Synoptic Survey Telescope, a wide-field telescope to study variable sources and address questions that range from asteroids that threaten Earth to the nature of dark energy.

We can look forward to exciting new discoveries in the near future as astronomers explore our distant past with instruments that haven’t even been built yet.

That’s all I have time for today. You can find other articles written by me on my blog, Simostronomy, at http://simostronomy.blogspot.com

End of podcast: