“We are irradiated all the time by cosmic rays,” says astrophysicist Noémie Globus, currently a post-doctoral researcher at New York University and the Simons Foundation’s Flatiron Institute. “Their effects are small but constant in every place on the planet where life could evolve, and the magnetic polarization of the muons and electrons is always the same. And even on other planets, cosmic rays would have the same effects.”
“The small amount of previous work on exoplanet oceans focused mostly on their climate impact,” said University of Chicago associate professor Dorian Abbot about a new study that suggests that in the search for alien life, planets exactly like Earth may not be best places to look. The research starts the process of “assessing the impact that ocean circulation has on nutrient cycling, biological productivity and, potentially, the detectability of life on exoplanets.”
Despite knowing from the geological record that the first multicellular organism, which eventually led to today’s technological civilization, took approximately 4 billion years, scientists still do not understand how life occurred, which has important implications for the likelihood of finding life elsewhere in the universe. “The odds that higher life forms might have emerged through evolutionary processes is comparable with the chance that a tornado sweeping through a junk yard might assemble a Boeing 747,” said British astrophysicist Fred Hoyle.
“These are utterly different worlds compared to our own Earth,” said Harvard University astronomer Li Zeng about the chances that water worlds are a common feature of the Milky Way, which was heightened by research using computer simulations showing that sub-Neptune-sized planets, that is, planets featuring radii about two to four times that of Earth, are likely to be water worlds, and not gas dwarfs surrounded by thick atmospheres as conventionally believed.
“For a long time, scientists were really focused on finding sun- and Earth-like systems. That’s all we knew. But we found out that there’s this whole crazy diversity in planets. We found planets as small as the moon. We found giant planets. And we found some that orbit tiny stars, giant stars and multiple stars,” said Elisa Quintana, a NASA Goddard astrophysicist who led the 2014 discovery of Earth-sized planet Kepler-186f about the use of NASA’s Discover supercomputer to determine whether any of more than 4,000 distinctly strange exoplanets discovered in the past two decades could support life.
Arthur C. Clarke, author of Space Odyssey 2001, famously warned “attempt no landing” to explore Europa, the most intriguing of Jupiter’s 79 moons, perhaps anticipating the “almost a racing certainty” that there’s alien life on the moon according to a leading British space scientist, Monica Grady, a professor of Planetary and Space Science at Liverpool Hope University. Grady proposes that the frigid ocean beneath Europa’s layer of ice up to 15 miles deep could harbor octopus-like creatures.
