Thanks to NASA, the Search for Habitable Worlds Just Got Easier

NASA
NASA

New NASA research will make it easier to find the planets out there that can support life. Detailed in the The Astrophysical Journal, the new model can simulate atmospheric conditions in a more comprehensive way, taking circulation of the atmosphere and other factors into account.

The search for habitable planets requires detailed modeling. The scope of the universe is simply too vast for scientists to spend time searching planet-by-planet. Instead, they calculate factors that would allow a planet to support liquid water—a requirement to support life as we know it—using simulations. For instance, it has to be just far enough from its parent star that the atmosphere isn't so cold that bodies of water freeze, but not so hot that they evaporate.

When planets are losing their oceans due to evaporation, they enter what's called a "moist greenhouse" state as the water vapor rises into the stratosphere and the hydrogen atoms break apart from the oxygen atoms to escape into space, eventually resulting in the loss of the planet's oceans. The new research details how a star's radiation influences how the atmosphere of an exoplanet circulates and plays a role in creating that moist greenhouse state. 

Planets that orbit a low-mass star—the most common kind of star in our galaxy—would have to be closer to that star than the Earth is to the Sun in order to support life, since a low-mass star is cooler and dimmer. The gravity from such a close star would slow down the rotation of the planet, and it might even become locked, with one side perpetually facing the star and one side perpetually facing away. (It would be as if the Eastern Hemisphere were always light and the Western Hemisphere were always dark.)

In turn, the planet would form a thick layer of clouds on the perpetually sunny side. The near-infrared radiation from the star—and cooler stars emit more of this radiation than hotter ones do—interacts with the water vapor in the air and the droplets and ice crystals in the clouds to warm up the air, creating the moist greenhouse state.

The moist greenhouse state could happen even at temperatures as low as those found in the tropical regions of Earth because of that near-infrared radiation interaction, according to the new model, but the study found that in exoplanets close to their stars, the process happens gradually enough that they could remain habitable. This more nuanced model will help guide scientists in their search for habitable planets near low-mass stars.

"As long as we know the temperature of the star, we can estimate whether planets close to their stars have the potential to be in the moist greenhouse state," study co-author Anthony Del Genio explained in a NASA press release. "Current technology will be pushed to the limit to detect small amounts of water vapor in an exoplanet's atmosphere. If there is enough water to be detected, it probably means that planet is in the moist greenhouse state."

A Super Pink Moon—the Biggest Supermoon of 2020—Is Coming In April

April's super pink moon will be extra big and bright (but still white).
April's super pink moon will be extra big and bright (but still white).
jakkapan21/iStock via Getty Images

The sky has already given us several spectacular reasons to look up this year. In addition to a few beautiful full moons, we’ve also gotten opportunities to see the moon share a “kiss” with Venus and even make Mars briefly disappear.

In early April, avid sky-gazers are in for another treat—a super pink moon, the biggest supermoon of 2020. This full moon is considered a supermoon because it coincides with the moon’s perigee, or the point in the moon’s monthly orbit when it’s closest to Earth. According to EarthSky, the lunar perigee occurs on April 7 at 2:08 p.m. EST, and the peak of the full moon follows just hours later, at 10:35 p.m. EST.

How a supermoon is different.

Since the super pink moon will be closer to Earth than any other full moon this year, it will be 2020’s biggest and brightest. It’s also the second of three consecutive supermoons, sandwiched between March’s worm moon and May’s flower moon. Because supermoons only appear about 7 percent bigger and 15 percent brighter than regular full moons, you might not notice a huge difference—but even the most ordinary full moon is pretty breathtaking, so the super pink moon is worth an upward glance when night falls on April 7.

The meaning of pink moon.

Despite its name, the super pink moon will still shine with a normal golden-white glow. As The Old Farmer’s Almanac explains, April’s full moon derives its misleading moniker from an eastern North American wildflower called Phlox subulata, or moss pink, that usually blooms in early April. It’s also called the paschal moon, since its timing helps the Catholic Church set the date for Easter (the word paschal means “of or relating to Easter”).

[h/t EarthSky]

Are Any of the Scientific Instruments Left on the Moon By the Apollo Astronauts Still Functional?

Apollo 11 astronaut Neil Armstrong left the first footprint on the Moon on July 20, 1969.
Apollo 11 astronaut Neil Armstrong left the first footprint on the Moon on July 20, 1969.
Heritage Space/Heritage Images/Getty Images

C Stuart Hardwick:

The retroreflectors left as part of the Apollo Lunar Ranging Experiment are still fully functional, though their reflective efficiency has diminished over the years.

This deterioration is actually now delivering valuable data. The deterioration has multiple causes including micrometeorite impacts and dust deposition on the reflector surface, and chemical degradation of the mirror surface on the underside—among other things.

As technology has advanced, ground station sensitivity has been repeatedly upgraded faster than the reflectors have deteriorated. As a result, measurements have gotten better, not worse, and measurements of the degradation itself have, among other things, lent support to the idea that static electric charge gives the moon an ephemeral periodic near-surface pseudo-atmosphere of electrically levitating dust.

No other Apollo experiments on the moon remain functional. All the missions except the first included experiment packages powered by radiothermoelectric generators (RTGs), which operated until they were ordered to shut down on September 30, 1977. This was done to save money, but also because by then the RTGs could no longer power the transmitters or any instruments, and the control room used to maintain contact was needed for other purposes.

Because of fears that some problem might force Apollo 11 to abort back to orbit soon after landing, Apollo 11 deployed a simplified experiment package including a solar-powered seismometer which failed after 21 days.

This post originally appeared on Quora. Click here to view.

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