Chaotic Astronomy

Planetarium software for telescope users and lay astronomers help viewers explore the sky. Learn about planetarium programs that help local telescope viewers from an observatory director in this free astronomy video.

Expert: Rocky Alvey & Billy Teets
Bio: Rocky Alvey is the assistant director of the Vanderbilt Dyer Observatory and has been involved in Astronomy since 1969.
Filmmaker: Dimitri LaBarge

Duration : 0:2:36

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Host:Dr. Kiki
Some newish Astronomy news, and a look at silly Geocentrists and conspiracy theorists.
Download or subscribe to this show at twit.tv/kiki.
We invite you to read, add to, and amend our show notes.
Thanks to Cachefly for the bandwidth for this show.

Duration : 1:0:28

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Satellites fitter with various telescopes orbit the earth. These telescopes detect different types of electromagnetic radiation.

Why are telescopes that detect different types of electromagnetic waves used to observe the universe?

First, electromagnetic waves span a spectrum. It is a chart-like-scale humans (scientists) devised. All electromagnetic waves travel through free space at 300,000 km/sec.
So the waves have wavelength and frequency (so many cycles of propagating waves in a second).
Frequency = 300,000,000 (m/s) / wavelength (m) or
Wavelength = 300,000,000 (m/s) / frequency (cycles/s).
Now a new name was adapted for frequency called ‘Hertz’ (1 cycle/s = 1 Hz).
If you look into any introductory book of higher Physics, the ‘EM’ spectrum is given in the appendix.
At long wavelengths, Radio waves (lengths of several kilometers to 0.3m or 30 cm) can be detected (‘received’ is the word) by Radio Telescopes using a particular repertoire of techniques & technologies. Microwaves (0.3m to 0.0005m or 0.5mm), still radio waves, but with a little bit different techniques can be also received. All our satellite communications systems employ it. Since our atmosphere heavily absorbs them, one needs to put up Microwave antennas above in the satellites.
Then comes the Far Infra Red (FIR) region with wavelengths down to ten millionths (a millionth of a meter is called 1 micron, 1 |u) there are various techniques again. About a century & quarter ago JC Bose did pioneering work for which he was accorded the honour ‘now’ of co-inventor of Radio. But that work needs to be taken up afresh. Then comes the middle IR. Same is the case here. In near IR (NIR) till 0.7 micron, vigorous work is in progress. This band is mainly for ‘Remotes’ for electronic equipment. But in all IR (FIR, MIR, NIR) space applications are limited except taking photos with those filters because atmospheric molecules interact freely producing IR and absorbing, as basically IR is ‘Heat waves’. One must go above the atmosphere for good work to be accomplished. The Optical ‘Fibre’ operates at 0.8 |u and is the mainstay in optical communications.
Then comes the work horse – 0.7 to 0.375 micron band in which we see the colours (VIBGYOR; Violet end near 0.375 micron & Red end at 0.7 micron). It is called the Visible Region. Telescope is meant for this region of spectrum. Eye is the main receptor/sensor for this part in electromagnetic waves. Almost all our knowledge of space is due to this window in the ‘EM’ spectrum and is called Optical window. If you are looking at a star or galaxy (either with aids like a ‘Telescope’ or without) or seeing its picture in all fantastic colours, you are indulging in Space (Astronomy) studies. 99% knowledge, work, analysis, Red-shift theories are all in Optical spectrum, a mere sliver of the spectrum with almost an ‘Octave’ bandwidth (it means the ratio of the highest to the lowest wavelengths is 2 : 1).
Beyond 0.375 micron (as I told you a micron is a millionth of a meter) we have Ultra Violet portion again divided into NUV, MUV & FUV merging with soft X rays of Nanometer (a billionth of a meter). Some UV cameras get sent in all missions in the Space probes and such programmes.
X rays : A telescope ‘Chandra’ is orbiting the Earth now to take pictures at wavelengths (my guess) of a fraction of a nanometer.
After that comes the ‘Gamma rays’ portion the sensors are complicated and expensive. These high energy and still higher energy radiations, being high energy radiations readily interact with the stuff of our atmosphere and the energy gets transferred into the excitation of those molecules thus decimating the ‘information’ content. So, one must go much above the atmosphere to build a telescope. Here (in this part of spectrum Electrons don’t have separate existence as they combine with Positrons to produce Gamma ray quanta).
Beyond these lie the zone of extremely high energy particles expressed in Energy units (we need to switch from the nomenclature of billionths to billionth billionths).
The whole spectrum (to my reckoning, in wavelengths spans the known region of 10^6 meters to 10^-12meter; a range with a ratio of end to end of 10^18 that we call 18 decades or that is about 60 octaves) and every region or octave has a different technique and equipment. You can’t have the same antenna to receive TV signals, Citizen band, satellite communications and data receiving, isn’t it? My effort is to outline here that all this constitutes the domain of ‘electromagnetic waves’.
The idea of a telescope (whether Optical, IR, Visible, Radio or UV) is to point it. I don’t want to venture into it even because it is a different kettle of fish altogether.
I haven’t got into the preliminary details even.

I’m so interested in science, mostly in astronomy. I’m 13 years old and I don’t know how can I improve my knowledge about it.

Can you tell me a good way to memorize stuff and how can I know more about astronomy.

Where i can learn things apart from science in school.

I would suggest a subscription to a magazine such as "Astronomy". I got this magazine when I was about your age, after a few years, if you still have an interest, I would then "graduate" up to "Sky & Telescope", it is good for more advanced amateurs. They both have good web-sites too.

http://icestories.exploratorium.edu Join scientists as they walk 1km from their Antarctic home station to work on the South Pole Telescope.

Duration : 0:6:42

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Science & Reason: http://tinyurl.com/ScienceReason

Astronomy vs Astrology – Best of Carl Sagan’s Cosmos (Part 15)

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Please subscribe to Science & Reason:
• http://www.youtube.com/Best0fScience
• http://www.youtube.com/ScienceMagazine
• http://www.youtube.com/ScienceTV
• http://www.youtube.com/FFreeThinker
• http://www.youtube.com/SagansCosmos
—

BEST OF CARL SAGAN’S “COSMOS”:

1) 10 Years After: Carl Sagan & Ann Druyan Reflect:

2) Lost Between Immensity And Eternity:

3) The Realm Of The Galaxies:

4) Our Galaxy, The Milky Way:

5) Our Solar System:

6) Eratosthenes And The Round Earth Model:

7) The Library Of Alexandria:

A Short History Of The Universe:

9) Artificial And Natural Selection:

10) The Cosmic Year:

11) Tree Of Life – 4 Billion Years Of Evolution:

12) The Miracle Of Life:

13) DNA – The Common Basis Of Life:

14) Abiogenesis The Origin Of Life:

15) Astronomy vs Astrology:

16) Pictures In The Sky:

17) Ancient Astronomy:

18) Triumph Of Modern Science Over Medieval Superstition:

19) The Mysterious Tonguska Event:

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Carl Edward Sagan, Ph.D. (1934-1996) was an American astronomer, astrochemist, author, and highly successful popularizer of astronomy, astrophysics and other natural sciences. He pioneered exobiology and promoted the Search for Extra-Terrestrial Intelligence (SETI).

He is world-famous for writing popular science books and for co-writing and presenting the award-winning 1980 television series “Cosmos: A Personal Voyage”, which has been seen by more than 600 million people in over 60 countries, making it the most widely watched PBS program in history.

A book to accompany the program was also published. He also wrote the novel “Contact”, the basis for the 1997 Robert Zemecki’s film of the same name starring Jodie Foster.

During his lifetime, Sagan published more than 600 scientific papers and popular articles and was author, co-author, or editor of more than 20 books. In his works, he frequently advocated skeptical inquiry, secular humanism, and the scientific method.

http://www.carlsagan.com

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Duration : 0:10:57

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I’m not interested in a toy telescope, but I’d like to keep the price below $500. I’m so confused by the options! I want to actually be able to see stuff, but I’m not getting another degree in optics in order to work the telescope. Any suggestions?

I have to be quick. In short, a Reflector on a Dobsonian mount. 8-inch aperture which allows you to see faint fuzzy things, as well as planets and multiple stars. Simple to operate. Get a star atlas to go with it. I’m sure others will expand on this.

I love Astronomy and simply considering going into that field. But astrophysics also is in my interest. Yes, i know the difference and like both. So what will decide my future? Money. Which one is economically wiser to chose?

‘Career’. They’re basically the same thing – very few astronomers can get away without doing a lot of physics these days. The days of observing something and reporting on it without trying to interpret it are past. And neither of them pay well considering how long you’ll be in school – 8-12 years of college, and then most people spend the first 5 years or so after the PhD doing various post-doc positions, which pay about 40k a year. If you can get a faculty job, that starts out between 40k and 70k, but those are hard to get – there are far more PhDs who want to teach than there are jobs for them, and many are teaching making 20k a year without benefits (yes, with a PhD). And NASA doesn’t pay a lot more, if you can get that job – there are even fewer of those. In fact, a lot of astronomers leave the field to make more money elsewhere within 10 years of getting their PhD – they simply can’t get a job in their own field.