Unique Teardrop Star Discovered by NASA Satellite

Gabriel Pérez Díaz (IAC)
Gabriel Pérez Díaz (IAC)

NASA built its Transiting Exoplanet Survey Satellite, or TESS, to search for worlds outside our solar system, but it can also detect bodies that are much bigger than the average planet. Its latest discovery—a teardrop-shaped, pulsating star dubbed HD74423—has roughly 1.7 times the mass of the sun, and it's the first star of its kind studied by scientists, CBS News reports.

An international team of astronomers published their findings about the star captured by TESS in the journal Nature Astronomy [PDF]. HD74423 is remarkable in many ways. Located 1500 light-years from Earth in the Milky Way galaxy, it shares a binary system with a red dwarf. The large star is tidally locked with the smaller one, meaning one side of HD74423 is always being pulled by its partner's gravitational pull in a tight orbit. This has resulted in its warped teardrop shape.

The fact that it's tidally locked also gives the star its unique pulsation pattern. Many stars like our own sun pulsate, which means they rhythmically become brighter and dimmer. When this phenomenon has been observed in the past, the starlight always fluctuates on all sides. Because it's distorted by its neighbor, HD74423 pulsates on only one side—a celestial anomaly. Even the star's composition is noteworthy. Study co-author Simon Murphy of Australia's Sydney Institute for Astronomy said that he first noticed the star because it was poor in metals, something that set it apart from other hot stars like it.

"We've known theoretically that stars like this should exist since the 1980s," study co-author Don Kurtz of Britain's University of Central Lancashire said in a press release. "I've been looking for a star like this for nearly 40 years and now we have finally found one."

HD74423 is just the latest groundbreaking discovery made by NASA's Transiting Exoplanet Survey Satellite. Earlier in 2020, TESS located a potentially habitable, Earth-sized planet 100 light-years away.

[h/t CBS News]

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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