Scientists Figure Out Why Many Returning Astronauts Need Glasses

NASA
NASA

The zero-G lifestyle does funny things to our bodily fluids. That’s the conclusion of one recent study, which may have found a reason for a common space travelers’ malady. The researchers presented their results [PDF] at the annual meeting of the Radiological Society of North America.

If we’re going to start sending humans to Mars and other distant destinations, we’re going to need to know if we can survive the trip. So astronauts are an incredible scientific resource, not only for what they do while in space, but also for what they experience. Living in orbit can shrink astronauts’ hearts and stretch their spines. It can also damage their ability to see: Numerous travelers who left Earth with 20/20 vision have returned to find they need glasses just to read or drive.

"People initially didn't know what to make of it, and by 2010 there was growing concern as it became apparent that some of the astronauts had severe structural changes that were not fully reversible upon return to earth,” lead author Noam Alperin of the University of Miami said in a statement.

Scientists call the phenomenon visual impairment intracranial pressure, or VIIP. The name is slightly misleading in its certainty. Researchers think the eye problems are the result of increased pressure inside astronauts’ heads, but they haven’t really been sure.

Alperin and his colleagues wondered if the problem might not be liquid—cerebrospinal fluid (CSF), to be precise. CSF is a crucial component of healthy brain and body function. It surrounds our brains and spinal cords and acts kind of like amniotic fluid in the womb, ensuring a flow of nutrients and removing waste. CSF is also somewhat adaptable and responds to changes in the position and angle of your body and head. It’s a good system, and it works.

At least where there’s gravity. The research team scanned the brains and eyeballs of seven different astronauts both before and after long stints aboard the International Space Station (ISS). They compared those scans with results from another nine astronauts who had only been on the ISS briefly.

There could be no doubt about it—longer stays in space were messing with the astronauts’ eyes. Their eyes were more flattened; their optic nerves showed more swelling; and, most interestingly, they had higher volumes of CSF in their eye sockets and in the CSF-producing part of the brain. The higher the CSF volume, the more trouble an astronaut had seeing.

"The research provides, for the first time, quantitative evidence obtained from short- and long-duration astronauts pointing to the primary and direct role of the CSF in the globe deformations seen in astronauts with visual impairment syndrome," Alperin said.

Identifying the source of the problem is the first step to correcting it. Alperin and NASA are now working to simulate the conditions that cause VIIP so they can figure out how to protect astronauts’ eyes in the future.

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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