See the most interesting work on the newly discovered super-Earth exoplanet that orbits the legendary Barnard's Star. This star is the only closest star (and now the second closest star system) of our own sun just six light-years away. Astronomers announced their new planet – called Barnard b (or GJ 699 b) – in November 2018. Last week (January 10, 2019) – at the 233rd meeting of the American Astronomical Society (ASA) in Seattle, Washington – Villanova University explained their new work showing that – although this world is probably cold (-170 degrees Celsius) – it may still have the potential to shelter primitive life.
Here's the thing about Barnard's Star b, whose mass is just over three times that of Earth. It orbits Barnard's Star – a red dwarf – every 233 days, about the same distance as Mercury orbits our sun. In the Star Barnard system, however, this distance is close to the star's snow line, that is, the point at which the heat of Barnard's star needed to hold the water molecules at the end of the vapor. After the snow line, the water can become ice.
For Barnard to have some form of life, astronomers said, the planet needs another source of heat. They suggested a large hot core of iron / nickel – just as Earth does – and increased geothermal activity.
Edward Guinan and Scott Engle de Villanova made the announcement; you can see their role as a poster of the AAS meeting. Guinan said:
Geothermal heating could support "living zones" beneath its surface, similar to the subterranean lakes found in Antarctica. We note that the surface temperature on the icy moon of Jupiter, Europe, is similar to Barnard b, but, due to tidal heating, Europe probably has liquid oceans beneath its icy surface.
Guinan and Engle have been studying Barnard's Star for a long time and were part of the discovery team that found the new planet. They have obtained high-precision photometry – that is, light measurements – from Barnard's Star (as well as dozens of other stars) in the last 15 years.
Terrestrial telescopes can see Barnard's Star, but not his planet … yet. Although very weak, it may be possible for Barnard B to be photographed by very large future telescopes, according to Guinan. He commented:
Such observations will clarify the nature of the planet's atmosphere, surface, and potential habitability.
The most significant aspect of Barnard's b-star discovery is that the two star systems closest to the Sun are now known to harbor planets. This supports previous studies based on data from the Kepler mission, inferring that planets may be very common throughout the galaxy, numbering tens of billions.
In addition, Barnard's Star is about twice as old as the sun – about 9 billion years, compared to 4.6 billion years for the sun. The universe produces planets the size of the Earth much longer than we, or even the sun itself, existed.
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Conclusion: A new study shows that the Barnard b (or GJ 699 b) exoplanet may have primitive life if it has a source of heat other than its sun, such as a large hot iron / nickel core – as Earth does. – and improved geothermal activity.
Source: X-Rays, UV, Optical Irradiations and the New Earth Supernova of Age of Barnard's Star – "Life Can Find a Way" on such a Cold Planet?
University Via Villanova