Earth-Sized World Found Orbiting a Star Just 22 Light-Years

www.sciencealert.com/earth-sized-world-found-orbiting-a-star-just-22-light-years-away
With the radius and mass in hand, the researchers were able to determine that the world has a density of 5.9 grams per cubic centimeter. Earth has a density of 5.51 grams per cubic centimeter. This suggests that LTT 1445 Ac is probably a rocky exoplanet very close to Earth in size and composition.


Now, the world is unlikely to host life as we know it. Its host star is a red dwarf, which is cooler and dimmer than the Sun, but the exoplanet has an orbital period of just 3.12 days, which means its temperature sits at around 260 degrees Celsius (500 degrees Fahrenheit).


Yet the ability to obtain clear transit data means we have a good shot at peering into its atmosphere.

Harry Keller
Studied Chemistry at California Institute of Technology (Caltech) (Graduated 1963)Author has 10.2K answers and 4.6M answer views3y
Related

Could extraterrestrial life be boron based rather than carbon based?

Having written a term paper for Linus Pauling on boron hydrides, I have a fleeting familiarity with boron. As a former chemistry professor, I should know a little bit about these things.

Boron and silicon are both very bad choices for the basis of life and for different reasons. The element chosen must be common in the universe in the first full row of the Periodic Table. It must be capable of forming complex but stable compounds. Really, only carbon will do.

Profile photo for Terry Bollinger
Terry Bollinger
Retired Chief Scientist, Defense Venture Catalyst InitiativeAuthor has 380 answers and 973.4K answer views3y

Besides silicon, boron, and carbon, what other elements or compounds could life also be based from?

All are a bit unlikely for actual living systems, frankly, mostly because silica and boron hydrolyze (react destructively) too easily with water. But boron sure is complicated and interesting, if you could find a good fluid medium for it. (Three-center electron bonding, wow!)

I did want to be sure to add the closest electron configuration of carbon that exists or can exist: boron nitride, which for example has both diamond and graphite allotropes, and forms the benzene ring analog borazene. Alas, even these compounds are quite delicate compared to carbon.

Keith Robison
, Ph.D. In Molecular&Cellular Biology; in Biopharma since 1996Author has 29.1K answers and 7.9M answer views4y
Related
What would a boron-based life form look like?

Boron chemistry is nothing like carbon chemistry - the kind on which every form of life we have ever seen is based. It is doubtful if boron could be the structure of any kind of life we might recognize. It simply cannot do all the things the carbon atom can do and each of which is essential for life as we know it.

Just any old atom cannot be the basis for the multitudes of activities that are necessary for life. Carbon is the only one that we know of - outside of sci-fi.

Martin J Pitt
Former Chartered Chemist and Chartered Chemical EngineerAuthor has 10K answers and 20.2M answer viewsUpdated 5y
Related
Would finding silicate or boron based life be as likely when searching for intelligence in the Universe, seeing that boron and silicates can bond to just as many molecules as carbon, and is more abundant in the Universe?

Daniel James Berger has given many answers on this general topic.

I will simply say that for the chemistry we know on earth, the known compounds are vastly dominated by complex carbon ones with hydrogen and other non-metals. It does not seem that other elements have the capability to form the number of complex molecules it takes to sustain even the simplest life forms. (Viruses are the simplest, but cannot exist on their own. They require all the complex mechanisms of a cell to reproduce, albeit they use those of other organisms.)

However, it is possible that under conditions which we would regard as extreme (and presently have limited experimental experience) such as molten lava under enormous pressures, then complex silicon, boron compounds might be enough to support some very simple life. Silicate minerals are quite complex, and boron has a lot of possibilities. There might therefore be some kind of non-carbon (or only a bit carbon) life forms in the very depths of our own planet.

Extremely high pressure chemistry is currently showing behaviour of elements which we would not have predicted, so there is an area of chemistry to be discovered.

journals.andromedapublisher.com/index.php/LHEP/article/view/166/85
Can Self-Replicating Species Flourish in the Interior of a Star?Luis A. Anchordoqui and Eugene M. ChudnovskyPhysics Department, Herbert H. Lehman College and Graduate School, The City University of New York250 Bedford Park Boulevard West, Bronx, NY 10468-1589, USA

Abstract - The existing view of biological life is that it evolves under suitable conditions in the low-temperature world of atoms and molecules on the surface of a planet. It is believed that any plausible extraterrestrial form of life must resemble the life on Earth that is ruled by the biochemistry of nucleic acids, proteins, and sugars. Going against this dogma, we argue that an advanced form of life based upon short-lived species can exist inside main-sequence stars like our Sun.