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Astronomy Picture of the Day -- Alpha Centauri: The Closest Star System
NASA ^ | July 03, 2011 | (see photo credit)

Posted on 07/03/2011 10:34:44 AM PDT by SunkenCiv

Explanation: The closest star system to the Sun is the Alpha Centauri system. Of the three stars in the system, the dimmest -- called Proxima Centauri -- is actually the nearest star. The bright stars Alpha Centauri A and B form a close binary as they are separated by only 23 times the Earth- Sun distance - slightly greater than the distance between Uranus and the Sun. In the above picture, the brightness of the stars overwhelm the photograph causing an illusion of great size, even though the stars are really just small points of light. The Alpha Centauri system is not visible in much of the northern hemisphere. Alpha Centauri A, also known as Rigil Kentaurus, is the brightest star in the constellation of Centaurus and is the fourth brightest star in the night sky. Sirius is the brightest even thought it is more than twice as far away. By an exciting coincidence, Alpha Centauri A is the same type of star as our Sun, causing many to speculate that it might contain planets that harbor life.

July 03, 2011

(Excerpt) Read more at 129.164.179.22 ...


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: alphacentauri; alphacentauria; alphacentaurib; apod; astronomy; science; xplanets
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To: SunkenCiv
Hey, where do you think humans came from in the first place? ;’)

I don't know, but I think the Cylons had something to do with it.

41 posted on 07/03/2011 8:34:05 PM PDT by Colonel_Flagg ("Mr. Romney and Mr. Obama are not rivals, they're running mates." - Rep. Thaddeus McCotter)
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To: Larry Lucido; SunkenCiv; TheOldLady

Here’s the link to the near star map.

http://www.solstation.com/47ly-ns.htm

These are using Java.


42 posted on 07/03/2011 8:35:24 PM PDT by bigheadfred ( He put... creatures... in our bodies... to control our minds.)
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To: Conan the Librarian

Weren’t the Robinsons on their way to Alpha Centauri when they became Lost in Space?


43 posted on 07/03/2011 8:37:38 PM PDT by rabidralph
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To: Larry Lucido

Two are in proximity (including the one most like our Sun), the red dwarf is .14 lightyears further from Earth, and a bit more than that from the binary.

http://www.solstation.com/stars/alp-cent3.htm

[snip] Proxima Centauri (or Alpha Centauri C) is only 4.22 light-years (ly) away (14:29:42.95-62:40:46.14, ICRS 2000.0) but is too dim to be seen with the naked eye. The two bright stars, Alpha Centauri A and B (14:39:36.5-62:50:02.3 and 14:39:35.1-60:50:13.8, ICRS 2000.0), are a little farther away at about 4.36 ly. They form a close binary that is separated “on average” by only about 24 times the Earth-Sun distance — an average orbital distnace or semi-major axis of 23.7 astronomical units (AUs) — which is only slightly greater than the distance between Uranus and the Sun (”Sol”). [/snip]


44 posted on 07/03/2011 9:02:48 PM PDT by SunkenCiv (Yes, as a matter of fact, it is that time again -- https://secure.freerepublic.com/donate/)
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To: Larry Lucido

Whoops, sorry, closer to Earth, and more than that distant from the binary.


45 posted on 07/03/2011 9:03:44 PM PDT by SunkenCiv (Yes, as a matter of fact, it is that time again -- https://secure.freerepublic.com/donate/)
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To: bigheadfred

Why didn’t you tell her the ingredients the first time she asked you? Then you would have had time to post in peace.

Fred! FredFredFred...

Helpful old lady hint: I make a lot of our condiments and stick the recipes on the fridge with magnets.


46 posted on 07/03/2011 9:26:55 PM PDT by TheOldLady (FReepmail me to get ON or OFF the ZOT LIGHTNING ping list.)
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To: Larry Lucido

Well, that explains it. Maybe I can get their email and strike up a conversation. Although I’m not sure I’d be able to keep up with someone on a massive, continuous sugar rush.


47 posted on 07/03/2011 9:29:25 PM PDT by TheOldLady (FReepmail me to get ON or OFF the ZOT LIGHTNING ping list.)
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To: NormsRevenge; SunkenCiv

>>> We should have launched craft that direction years ago.
Ya never know, it might get there.. eventually. :-)

A year or two ago on a thread regarding the Voyager space probes launched thirty years ago, I did the math. To reach Alpha Centauri at their current speeds would take 98,000 years, give or take.

Depending on the lights.


48 posted on 07/03/2011 9:50:42 PM PDT by tlb
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To: bigheadfred

Thank you, Fred, and for Post #40 as well.


49 posted on 07/03/2011 10:18:52 PM PDT by TheOldLady (FReepmail me to get ON or OFF the ZOT LIGHTNING ping list.)
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To: TheOldLady

I did tell her. Every time she asked.


50 posted on 07/03/2011 10:31:23 PM PDT by bigheadfred ( He put... creatures... in our bodies... to control our minds.)
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To: bigheadfred

Hmmm... It’s time to shut down the computer and pay attention to her.


51 posted on 07/03/2011 10:48:36 PM PDT by TheOldLady (FReepmail me to get ON or OFF the ZOT LIGHTNING ping list.)
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To: bigheadfred
Asimov was always my favorite but Niven and Pournelle were
both great.Carl Sagan was a good writer too IMHO until he let his politics carry over too much into his stories. I read my sci-fi to escape that B.S..
52 posted on 07/04/2011 12:04:42 AM PDT by WePledge (Ich werde fur immer ein Hollenhund werden. Semper Fidelis)
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To: WePledge

Azimov always seemed a little dry for me. Jack Chalker I like.


53 posted on 07/04/2011 4:38:56 AM PDT by bigheadfred ( He put... creatures... in our bodies... to control our minds.)
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To: tlb; NormsRevenge

The Voyager probes are moving faster than any craft humans have ever launched, but using propulsion that isn’t based on simple chemistry, the distance could be bridged in less than 20,000 years. ;’)

http://nmp.nasa.gov/ds1/tech/ionpropfaq.html
http://www.google.com/search?q=plasma+engine


54 posted on 07/04/2011 10:21:54 AM PDT by SunkenCiv (Yes, as a matter of fact, it is that time again -- https://secure.freerepublic.com/donate/)
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To: bigheadfred

Hey, nice! I have Javascript turned off in my browser, but I have Java turned on, so this worked!


55 posted on 07/04/2011 10:28:34 AM PDT by SunkenCiv (Yes, as a matter of fact, it is that time again -- https://secure.freerepublic.com/donate/)
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To: KevinDavis; annie laurie; Knitting A Conundrum; Viking2002; Ernest_at_the_Beach; Mmogamer; ...
Note: this topic is from 7/03/2011.
 
X-Planets
· join · view topics · view or post blog · bookmark · post new topic · subscribe ·
Google news searches: exoplanet · exosolar · extrasolar ·

56 posted on 11/26/2015 11:32:58 PM PST by SunkenCiv (Here's to the day the forensics people scrape what's left of Putin off the ceiling of his limo.)
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