Over at Centauri Dreams is a piece by Andrew LePage on the questions over exoplanets around Centauri B, on the second anniversary of a (possible) detection.
Alpha Centauri (or α Centauri, if you prefer) is a binary star system, 4.37 light years from the Sun, and the closest star system to the Solar System. "Alpha Centauri A" is the primary star, "Alpha Centauri B" is the (slightly smaller) companion, and a planet, known as Alpha Centauri Bb was detected in October 2012 using data from the HARPS spectrograph.
However there is still some scepticism about about the the data and techniques used to establish the existence of Alpha Centauri Bb, and the Centauri Dreams article goes into detail about the background of the search, the findings to date and the current efforts.
While this planet, designated α Centauri Bb, was hardly the Earth-like planet for which interstellar travel enthusiasts had been waiting so long, its presence demonstrated that the closest star system to us harbored at least one planet and held the promise of more to be discovered. But two years after this momentous announcement, many questions still remain and this important discovery has yet to be independently confirmed.
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Astronomers have reportedly discovered an Earth-like exoplanet in the habitable zone of Proxima Centauri, one of the closest stars to our Sun. However, the claim is based on an anonymous source who is said to have leaked the news ahead of an announcement by the European Southern Observatory:
[In] what may prove to be the most exciting find to date, the German weekly Der Spiegel [translation] announced recently that astronomers have discovered an Earth-like planet orbiting Proxima Centauri, just 4.25 light-years away. Yes, in what is an apparent trifecta, this newly-discovered exoplanet is Earth-like, orbits within it's sun's habitable zone, and is within our reach. But is this too good to be true? [...] Citing anonymous sources, the magazine stated:
The still nameless planet is believed to be Earth-like and orbits at a distance to Proxima Centauri that could allow it to have liquid water on its surface — an important requirement for the emergence of life. Never before have scientists discovered a second Earth that is so close by.
In addition, they claim that the discovery was made by the European Southern Observatory (ESO) using the La Silla Observatory's reflecting telescope. Coincidentally, it was this same observatory that announced the discovery of Alpha Centauri Bb back in 2012, which was also declared to be "the closest exoplanet to Earth". Unfortunately, subsequent analysis cast doubt on its existence, claiming it was a spurious artifact of the data analysis.
However, according to Der Spiegel's unnamed source – whom they claim was involved with the La Silla team that made the find – this latest discovery is the real deal, and was the result of intensive work. "Finding small celestial bodies is a lot of hard work," the source was quoted as saying. "We were moving at the technically feasible limit of measurement." The article goes on to state that the European Southern Observatory (ESO) will be announcing the finding at the end of August. But according to numerous sources, in response to a request for comment by AFP, ESO spokesman Richard Hook refused to confirm or deny the discovery of an exoplanet around Proxima Centauri.
[Continues...]
(Score: 2) by tangomargarine on Monday October 20 2014, @07:21PM
http://en.wikipedia.org/w/index.php?title=Sid_Meier's_Alpha_Centauri [wikipedia.org]
"Is that really true?" "I just spent the last hour telling you to think for yourself! Didn't you hear anything I said?"
(Score: 0) by Anonymous Coward on Tuesday October 21 2014, @02:06PM
What a great game, perhaps the greatest of them all.
(Score: 2) by aristarchus on Monday October 20 2014, @08:01PM
How big is this alleged exoplanet? About the size of a bb, you say? Wait a minute, is this just coincidence, or is someone pulling our leg? Wait, here is a citation by Stronzo Bestiale [parolacce.org]
(Score: 2) by VLM on Monday October 20 2014, @09:33PM
many questions still remain and this important discovery has yet to be independently confirmed.
Well that settles it, I guess we're going to have to send a probe.
(hey any excuse for that is a good excuse)
(Score: 0) by Anonymous Coward on Monday October 20 2014, @09:39PM
Since when you need an excuse for guessing?
(Score: 2) by VLM on Monday October 20 2014, @09:46PM
I needed the excuse for not pulling off a joke about redirecting the probe originally aimed at Uranus to planet goatse orbiting star DD or whatever but I couldn't quite make it work. So I needed an excuse, you know, we'll do it for science and stuff.
(Score: 0) by Anonymous Coward on Tuesday October 21 2014, @12:46AM
There are hundreds of stars less than 3 times the distance of Alpha Centauri. At least one of them should have a decent planetary system. We should just wait longer to get more interesting data.
(Score: 3, Informative) by takyon on Tuesday October 21 2014, @01:02AM
ATLAST: The Gargantuan Telescope Designed to Find Life on Other Planets [theatlantic.com]
NASA Team Lays Plans to Observe New Worlds [nasa.gov]
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 1, Funny) by Anonymous Coward on Tuesday October 21 2014, @07:22AM
According to Wikipedia, the orbital period of Alpha Centauri Bb, that is the length of its year, is about 3.2 earth days. That is, it has about two anniversaries per week.
In two earth years, it therefore has 228 anniversaries.