from the my-God,-it's-full-of-ice-hockey-rinks dept.
Astronomers have spotted a potential second planet circling our nearest neighbor.
The red dwarf star Proxima Centauri is 'just' 4.2 light years away and is already known to have one roughly Earth sized planet dubbed Proxima b, which orbits within the habitable zone (where liquid water could exist on the surface.)
If confirmed, the new world would be Proxima c, however
"It is only a candidate," Mario Damasso, of the University of Turin in Italy, said during a presentation today (April 12) at the Breakthrough Discuss conference
Damasso['s], fellow presenter Fabio Del Sordo of the University of Crete and their colleagues analyzed observations of Proxima Centauri made by the High Accuracy Radial velocity Planet Searcher instrument. HARPS, which is installed on a telescope at the European Southern Observatory's La Silla Observatory in Chile, notices the tiny stellar movements induced by the gravitational tugs of orbiting planets. The instrument's data helped lead to the discovery of Proxima b (and many other alien worlds as well).
The potential planet Proxima c is a minimum of six times the mass of Earth and 1.5 AUs from the dim star. As a result it is almost certainly too cold for life with an equilibrium temperature around -390 degrees Fahrenheit (-234 degrees Celsius).
Sadly Proxima b is likely not very hospitable either as it is almost certainly tidally locked to the star causing blistering heat on one side and extreme cold on the other, it is also not unlikely to have lost its atmosphere to solar flares long ago.
Things aren't looking too hospitable close to home so far.
Related Stories
Proxima Centauri b confirmed as nearest exoworld
Four years ago, scientists made one of the most exciting exoplanet discoveries so far, a rocky planet similar in size to Earth orbiting the nearest star to the sun, Proxima Centauri. While the detection seemed solid, more confirmation is always good, and now the ESPRESSO spectrograph on the Very Large Telescope (VLT) in Chile has provided that extra and more detailed confirmation. The news was announced by the University of Geneva (UNIGE) on May 28, 2020.
[...] Proxima Centauri b is very similar in size to Earth, with a mass of 1.17 Earth masses. It orbits its star in only 11.2 days, in contrast to our Earth's year-long orbit around our sun. That means Proxima Centauri b is a lot closer to its star than Earth is to the sun. But, because the star is a red dwarf – much smaller and cooler than our sun – its orbit is indeed within the habitable zone of Proxima Centauri. Interestingly, Proxima Centauri b receives about the same amount of solar energy from its star that Earth does from our sun.
[...] The mass of Proxima b was previously estimated to be 1.3 Earth masses. The accuracy of the new measurement of 1.17 Earth masses is unprecedented, according to Michel Mayor, the "architect" of all ESPRESSO-type instruments:
ESPRESSO has made it possible to measure the mass of the planet with a precision of over one-tenth of the mass of Earth. It's completely unheard of.
The new confirmation of Proxima Centauri b is exciting, but there may be more surprises in store ... there is also possible evidence of another and smaller planet in the newest data. A secondary detection was also made, although it isn't certain whether it is actually a planet. If it is, it is even smaller than Proxima Centauri b. [...] If it is a planet, it would be more akin to Mars or Mercury in size and mass – estimated at a minimum Earth mass of 0.29 ± 0.08 – and orbits the star in only 5.15 days. It wouldn't be too surprising, though, in that low-mass stars like red dwarfs tend to have multiple planets in their systems. More observations will be required to either confirm or refute this possible second planet.
Journal Reference
Mascareño, A. Suárez, Faria, J. P., Figueira, P., et al. Revisiting Proxima with ESPRESSO, (https://arxiv.org/abs/2005.12114v1)
Proxima Centauri - Planetary system
Previously: ESO Confirms Reports of Proxima Centauri Exoplanet
Proxima b May Have Oceans
Dust Belts and Possible Additional Exoplanet Spotted Around Proxima Centauri
First Light for VLT's ESPRESSO Exoplanet Hunter
Very Large Telescope's ESPRESSO Combines Light From All Four Unit Telescopes for the First Time
Proxima Centauri's No Good, Very Bad Day
High Levels of Ultraviolet Radiation Should Not Preclude Life on Exoplanets
Icy second planet potentially spotted orbiting Proxima Centauri
Earth-like planet spotted orbiting Sun's closest star
Astronomers have discovered a third planet orbiting Proxima Centauri, the star closest to the Sun. Dubbed Proxima Centauri d, the newly spotted world is probably a bit smaller than Earth, and well within the habitable zone of its host star — meaning that it could have oceans of liquid water that can potentially harbour life.
"It's showing that the nearest star probably has a very rich planetary system," says Guillem Anglada-Escudé, an astronomer at the Institute for Space Sciences in Barcelona, Spain, who led the team that in 2016 discovered the first planet to be seen orbiting Proxima Centauri.
Astronomer João Faria and his collaborators detected Proxima Centauri d by measuring tiny shifts in the spectrum of the star's light as the planet's gravity pulled it during orbit. The team used a state-of-the art spectrograph called ESPRESSO at the Very Large Telescope, a system of four 8.2-metre telescopes at the European Southern Observatory in Cerro Paranal, Chile. The results were published on 10 February in Astronomy & Astrophysics.
A candidate short-period sub-Earth orbiting Proxima Centauri
We detect a signal at 5.12 ± 0.04 days with a semi-amplitude of 39 ± 7 cm s−1. The analysis of subsets of the ESPRESSO data, the activity indicators, and chromatic RVs suggest that this signal is not caused by stellar variability but instead by a planetary companion with a minimum mass of 0.26 ± 0.05 M⊕ (about twice the mass of Mars) orbiting at 0.029 au from the star. The orbital eccentricity is well constrained and compatible with a circular orbit.
Previously: "Earth-Like" Exoplanet Found in Habitable Zone of Proxima Centauri
ESO Confirms Reports of Proxima Centauri Exoplanet
Dust Belts and Possible Additional Exoplanet Spotted Around Proxima Centauri
Icy second planet potentially spotted orbiting Proxima Centauri
Proxima Centauri b Confirmed Using VLT's ESPRESSO, Possible Third Exoplanet Found in System
(Score: 2, Informative) by RandomFactor on Saturday April 13 2019, @10:24PM
Lazy author should have included related coverage of Proxima b's discovery here [soylentnews.org] and here [soylentnews.org]
В «Правде» нет известий, в «Известиях» нет правды
(Score: -1, Redundant) by Anonymous Coward on Saturday April 13 2019, @10:54PM (3 children)
Until we have proof of this planet's existence, anything written about it or its inhabitants is speculative science fiction. I for one believe that the inhabitants are Chinese based on the planet's temperature and the spiciness of the Szechuan dinner I had yesterday.
(Score: 1) by RandomFactor on Saturday April 13 2019, @11:33PM (2 children)
Sounds pretty likely, though I'm not going to bet my retirement on it :-p
В «Правде» нет известий, в «Известиях» нет правды
(Score: 1) by fustakrakich on Sunday April 14 2019, @12:36AM (1 child)
For sure they found the rebel base...
La politica e i criminali sono la stessa cosa..
(Score: 2) by Arik on Sunday April 14 2019, @12:47AM
There might even be a thin strip of twilight where things are livable, in some sense at least.
If laughter is the best medicine, who are the best doctors?
(Score: 0) by Anonymous Coward on Saturday April 13 2019, @11:26PM
I spotted a watery third planet off Alpha Centauri.
Send me 10 bucks and 50 cents via paypal to view the image.
(Score: 0) by Anonymous Coward on Sunday April 14 2019, @03:02AM
Sounds like it would be just the right temperature at the permanent terminator [wikipedia.org].
(Score: 2) by cosurgi on Sunday April 14 2019, @11:04AM (1 child)
Since reading this trilogy, every mention about proxima centauri being only 4.2ly away will always remind me about it.
#
#\ @ ? [adom.de] Colonize Mars [kozicki.pl]
#
(Score: 2) by PartTimeZombie on Sunday April 14 2019, @10:39PM
The summary says:
but it doesn't need the quote marks, as 4.2 light years is really close.
According to Wikipedia it will get as close as perhaps 3 light years in only 30,000 years or so.
Interestingly, in 'only' 1.4 million years Gliese 710 will approach within 0.178 light years of our sun, which will cause trouble, no doubt.