Astronomers Watched a Star System Die

This is an artist’s impression of a white dwarf (burned-out) star accreting rocky debris left behind by the star’s surviving planetary system. It was observed by Hubble in the Hyades star cluster. At lower right, an asteroid can be seen falling toward a Saturn-like disk of dust that is encircling the dead star. Infalling asteroids pollute the white dwarf’s atmosphere with silicon. Credit: NASA, ESA, and G. Bacon (STScI)

About 570 light years from Earth lies WD 1145+017, a white dwarf star. In many respects it’s a typical white dwarf star. Its mass is about 0.6 solar masses, and its temperature is about 15,900 Kelvin. But five years ago, a team of astronomers wrote a paper on the white dwarf, showing that something unusual was going on.

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Because of Coronavirus Lockdowns, Europe is Having the Same Drop in Pollution that we Saw in China

Satellite data shows that air pollution over European cities has dropped during coronavirus lockdowns. Image Credit: contains modified Copernicus Sentinel data (2019-20), processed by KNMI/ESA

The pandemic caused by the novel coronavirus is creating all kinds of chaos for human society. But for the dear old Earth, and the humans and creatures that breathe its air, it’s a bit of a reprieve. Mirroring what happened in China during lock-down, Europe is now seeing the same drop in air pollution.

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Astronomers Define the “Really Habitable Zone”. Planets Capable of Producing Gin and Tonic

Gin and tonic. Image Credit: By NotFromUtrecht - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=8529628

A hospitable star that doesn’t kill you with deadly flares. A rocky planet with liquid water and an agreeable climate. Absence of apocalyptic asteroid storms. No pantheon of angry, vengeful, and capricious gods. These are the things that define a habitable planet.

Now some scientists are adding one more criterion to the list: gin and tonic.

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This Galaxy is the Very Definition of “Flocculent”

This image taken by the NASA/ESA Hubble Space Telescope shows the galaxy NGC 4237. Located about 60 million light-years from Earth in the constellation of Coma Berenices (Berenice's Hair), NGC 4237 is classified as a flocculent spiral galaxy. This means that its spiral arms are not clearly distinguishable from each other, as in “grand design” spiral galaxies, but are instead patchy and discontinuous. This gives the galaxy a fluffy appearance, somewhat resembling fluffed cotton. Image Credit: ESA/Hubble & NASA, P. Erwin et al.

I know you’re Googling “flocculent” right now, unless you happen to be a chemist, or maybe a home brewer.

You could spend each day of your life staring at a different galaxy, and you’d never even come remotely close to seeing even a tiny percentage of all the galaxies in the Universe. Of course, nobody knows for sure exactly how many galaxies there are. But there might be up to two trillion of them. If you live to be a hundred, that’s only 36,500 galaxies that you’d look at. Puts things in perspective.

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Are the Gaps in These Disks Caused by Planets?

Are baby planets responsible for the gaps and rings we’ve spotted in the disks that surround distant, young stars? Image Credit: C. Pinte et al, 2020

Astronomers like observing distant young stars as they form. Stars are born out of a molecular cloud, and once enough of the matter in that cloud clumps together, fusion ignites and a star begins its life. The leftover material from the formation of the star is called a circumstellar disk.

As the material in the circumstellar disk swirls around the now-rotating star, it clumps up into individual planets. As planets form in it, they leave gaps in that disk. Or so we think.

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This Powerful Ion Engine Will Be Flying on NASA’s DART Mission to Try and Redirect an Asteroid

The NEXT-C ion thruster in a vacuum chamber at NASA's Glenn Research Center. Image Credit: NASA/Bridget Caswell

Despite humanity’s current struggle against the novel coronavirus, and despite it taking up most of our attention, other threats still exist. The very real threat of a possible asteroid strike on Earth in the future is taking a backseat for now, but it’s still there.

Though an asteroid strike seems kind of ephemeral right now, it’s a real threat, and one that—unlike a coronavirus—has the potential to end humanity. Agencies like NASA and the ESA are still working on their plans to protect us from that threat.

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This is Foam, Made in Space

An early image from the ESA's Foam-Coarsening on the ISS. Image Credit: ESA

Say hello to Space Foam.

The ESA has a science lab on the International Space Station called Columbus. Inside that lab is the Fluid Science Laboratory, dedicated to studying the behaviour of fluids in microgravity. Currently, that lab is being used to study a substance most of us probably don’t spend much time thinking about: foam.

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Good News! The New Strategy of Using InSight’s Arm to Push the Mole Seems to be Making Progress.

There’s at least one small bit of good news in these challenging Covid-19 times. And it’s playing out on the surface of Mars. In a brief Tweet, NASA says that using InSight’s robotic arm to push the Mole into the ground is working, somewhat.

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