TESS, the Transiting Exoplanet Survey Satellite, has just confirmed the discovery of a star and orbiting exoplanet the size of Earth roughly 53 lightyears away.
TESS has found many an exoplanet in its short tenure, however, finding something the approximate size of Earth with a star an equivalent distance to that of our sun.
Hence the jubilation of NASA at the news we could be looking at a plan B for when the oceans boil and the upper atmosphere is a junkyard of discarded space military apparatus.
The star named HD 21749 is around 70% the mass of our sun and two planets exist in this duo of a solar system, as opposed to our eight.
The Earth-sized planet is HD 21749c (C) and takes eight days to orbit the star and the additional planet is HD 21749b (B) and takes a considerably larger route which equates to a 36-day orbit around.
The differentiating factors for C being potentially more host-friendly than (B) comes down to some key points:
- B is approximately 23 times the Earth's mass and 2.3 times its radii, meaning the gravity would be far too strong to withstand.
- The orbit time is inconvenient, to say the least.
- The density of the planet is presumed to be "less than solid" with some more investigation required.
C appears to be the more palatable of the two for reasons mentioned previously and with some more investigation with the Magellan II telescope in Chile, we can get a more accurate depiction of the density and habitable probability of C.
Now we just have to figure out a way to accomplish 90% of lightspeed to make the journey around 50 years to complete.