Astrobiologists find that the presence of oxygen in a planet’s atmosphere may not necessarily mean that life exists there.
Scientists and E.T. enthusiasts may have to rethink an allegedly telltale sign that a planet has life.
The presence of oxygen, specifically O2 , in a planet’s atmosphere has long been thought to be a near-certain signal that there are, or at least were, living organisms engaging in photosynthesis on the planet. But new research suggests that oxygen can exist in large quantities without being produced by living things.
A study published Thursday in Scientific Reports found that some planets could have “abiotic” oxygen, produced through a a photocatalytic reaction of titanium oxide
Data has been flooding in from the nation’s latest space telescope, one with a 30-meter-diameter mirror (the Hubble’s, for comparison, was 2.4 meters). The initial searches for signs of life on exoplanets by 2020s telescopes found so many tantalizing hints. The new telescope, with thousands of times the capability, has searched hundreds of the nearest Earth-size exoplanets and found something astonishing: A large fraction show unusual chemistry in their atmospheres.
We are working hard to understand if any of the unusual chemistry can be attributed to gases produced by life. If geophysical or other contributions can be ruled out, we might establish that our galaxy is teeming with life, or at least microbial life.
If we instead hit a dead end with ambiguous chemical signals, we’ll need to go to the next step. Thanks to telomere gene therapy that has extended my life, I am willing and able to direct an even more capable space telescope, but that isn’t good enough. We will have to leave it to the next generations to figure out how to send the first interstellar space probes to actually travel up to tens of light years away to visit the other Earths.
How would you like to journey through space for a quick tour of all those alien worlds astronomers have discovered?
No spaceship, you say? No worries. An enterprising graduate student at the University of Leicester in England has created an amazing new exoplanet video that lets you fly by 1,774 extrasolar planets in 1,081 star systems–all from the comfort of your favorite chair.
There is a vast range of different time-scales on which exoplanets orbit their host stars, from things which orbit at many times the separation of the Earth and Sun over many hundreds of years, right down to planets which orbit so close to their star that they complete each orbit in just a few hours. It fascinating just how much these exoplanetary systems differ from our own system in scale.
To date, there are 1,776 confirmed exoplanets and 1,082 planetary systems.