From Scientific
American:
Orange skies, icy dunes and methane
clouds—no, it’s not some post-apocalyptic picture of Earth. It’s what Saturn’s
moon Titan might look like to explorers. While it doesn’t sound like paradise,
scientists, including my colleagues in chemistry at the University of
Colorado Boulder, think Titan has enough in common with Earth that
it’s worth studying. But is there life on Titan? Right now, we can’t say for
sure.
Cassini-Huygens, the mission that discovered
most of what’s known about Titan, ended in 2017. Data from Cassini, which orbited Saturn, and Huygens, Cassini’s
surface lander on Titan, confirmed that Titan has water as well as numerous
reserves of carbon-containing chemicals. Life on Earth is based on complex
carbon-based chemicals, like DNA. Based on what’s known about Earth’s history,
finding water and carbon-containing chemicals mixed up in a primordial soup
could be the right recipe for life. Enter Dragonfly, a proposed mission to explore
Titan’s surface using a lander equipped with helicopter-like propellers.
Dragonfly’s mission could help us understand our own primordial evolution—or
even discover extraterrestrial life.
Titan has some features reminiscent of Earth. There are clouds, lakes (albeit filled with oil, not water)
and even tides. Storms form on Titan’s surface, just like on Earth.
But Titan’s storms are made of methane, not water vapor. And although Titan’s
temperature is well above absolute zero, it’s still absolutely freezing, with
an average surface temperature of minus 290 degrees Fahrenheit, it has a dense
atmosphere, so you wouldn’t need a pressurized space suit to walk around—just
oxygen and many, many layers of very warm clothes.
While scientists don’t know yet if life could exist on
Titan, Cassini-Huygens’ discovery of a buried saltwater ocean on Titan was a
promising sign for primordial soup. Cassini-Huygens managed to find the ocean
without ever getting its feet wet. Electromagnetic waves, like the ones that
let your car stereo pick up your favorite country music, can tell scientists a
lot about the materials they pass through.
For the rest click
here.
No comments:
Post a Comment