Universe Today
The hunt for exoplanets has been heating up in recent years. Since it began its mission in 2009, over four thousand exoplanet candidates have been discovered by the
Kepler mission
, several hundred of which have been confirmed to be "Earth-like" (i.e.
terrestrial
). And of these, some 216 planets have been shown to be both terrestrial and located within their parent star's
habitable zone
(aka. "Goldilocks zone").
But in what may prove to be the most exciting find to date, the German weekly
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 its sun's habitable zone, and is within our reach. But is this too good to be true?
For over a century, astronomers have known about Proxima Centauri and believed that it is likely to be part of a trinary star system (along with Alpha Centauri A and B). Located just 0.237 ± 0.011 light years from the binary pair, this low-mass red dwarf star is also 0.12 light years (~7590 AUs) closer to Earth, making it the closest star system to our own.
In the past, the Kepler mission has revealed several Earth-like exoplanets that were deemed to be likely habitable. And recently, an international team of researchers narrowed the number of potentially-habitable exoplanets in the Kepler catalog down to the
20 that are most likely to support life
. However, in just about all cases, these planets are hundreds (if not thousands) of light years away from Earth.
Knowing that there is a habitable planet that a mission from Earth could reach within our own lifetimes is nothing short of amazing! But of course, there is reason to be cautiously optimistic. Citing anonymous sources, the magazine stated:
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.
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Artist's impression of the Earth-like exoplanet discovered orbiting Alpha Centauri B by the European Southern Observatory on October 17, 2012. Credit: ESO
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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. "We are not making any comment," he is reported as saying.
What's more, the folks at
Project Starshot
are certainly excited by the news. As part of
Breakthrough Initiatives
- a program founded by Russian billionaire Yuri Milner to search for intelligent life (with backing from
Stephen Hawking and Mark Zuckerberg
) - Starshot intends to send a laser-sail driven-nanocraft to Alpha Centauri in the coming years.
This craft, they claim, will be able to reach speeds of up to 20% the speed of light. At this speed, it will able to traverse the 4.37 light years that lie between Earth and Alpha Centauri in just 20 years. But with the possible discovery of an Earth-like planet orbiting Proxima Centauri, which lies even closer, they may want to rethink that objective.
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Project Starshot, an initiative sponsored by the Breakthrough Foundation, is intended to be humanity's first interstellar voyage. Credit: breakthroughinitiatives.org
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As Professor Phillip Lubin - a professor at the University of California, Santa Barbara, the brains behind Project Starshot, and a key advisor to NASA's
DEEP-IN
program - told Universe Today via email:
Naturally, there is the desire (especially amongst exoplanet enthusiasts) to interpret the ESO's refusal to comment either way as a sort of tacit confirmation. And knowing that industry professionals are excited it about it does lend an air of legitimacy. But of course, assuming anything at this point would be premature.
If the statements made by the unnamed source, and quoted by
Der Speigel
, are to be taken at face value, then confirmation (or denial) will be coming shortly. In the meantime, we'll all just need to be patient. Still, you have to admit, it's an exciting prospect: an Earth-like planet that's actually within reach! And with a mission that could make it there within our own lifetimes. This is the stuff good science fiction is made of, you know.
Further Reading: Der Speigel