A Newly Discovered Galaxy Has a Shocking Feature—No Dark Matter

Gemini Observatory/NSF/AURA/Keck/Jen Miller
Gemini Observatory/NSF/AURA/Keck/Jen Miller

Astronomers have discovered a galaxy that upends what we thought about galaxies. A new study in Nature reports that this one has almost no dark matter—unlike just about every other galaxy ever observed.

Called NGC1052-DF2, the new galaxy is an ultra-diffuse galaxy, a type that is large but still appears faint and contains few stars. Ultra-diffuse galaxies in themselves aren't very rare, but scientists have never observed one without a significant amount of dark matter, a component thought to be a vital part of the galaxy-formation process.

"For decades, we thought that galaxies start their lives as blobs of dark matter," said Yale University astronomer Pieter van Dokkum, lead author of the study, in a press release. "NGC1052-DF2 challenges the standard ideas of how we think galaxies form."

Gemini Observatory/NSF/AURA/Keck/Jen Miller/Joy Pollard

The research team first observed the galaxy, located 6.5 billion light-years from the Milky Way, using the Dragonfly Telephoto Array in New Mexico, a telescope designed specifically for finding ultra-diffuse galaxies. They also gathered data from the Gemini North Observatory and W.M. Keck Observatory in Hawaii and several other telescopes around the world.

They discovered the lack of dark matter in the galaxy from spectral data that showed that objects in the system were moving slower than expected, meaning the system didn't have a lot of mass. By their calculations, the mass of the galaxy can be almost entirely attributed to the stars, meaning there is little dark matter there—a contrast to just about any other galaxy observed. (Meanwhile, in 2016, van Dokkum and his team found an ultra-diffuse galaxy that is made up of 99.9 percent dark matter.)

"There is no theory that predicted these types of galaxies," van Dokkum said. “The galaxy is a complete mystery, as everything about it is strange. How you actually go about forming one of these things is completely unknown."

The discovery provides more evidence for the dark matter hypothesis, and means that it isn't just a part of galaxy formation. It exists on its own, separate from its role as a galaxy component. The research team has already found a few other diffuse galaxies that appear to resemble this new galaxy, and plans to continue searching for and analyzing these dark-matter-free systems.

Amazon's Under-the-Radar Coupon Page Features Deals on Home Goods, Electronics, and Groceries

Stock Catalog, Flickr // CC BY 2.0
Stock Catalog, Flickr // CC BY 2.0

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Now that Prime Day is over, and with Black Friday and Cyber Monday still a few weeks away, online deals may seem harder to come by. And while it can be a hassle to scour the internet for promo codes, buy-one-get-one deals, and flash sales, Amazon actually has an extensive coupon page you might not know about that features deals to look through every day.

As pointed out by People, the coupon page breaks deals down by categories, like electronics, home & kitchen, and groceries (the coupons even work with SNAP benefits). Since most of the deals revolve around the essentials, it's easy to stock up on items like Cottonelle toilet paper, Tide Pods, Cascade dishwasher detergent, and a 50 pack of surgical masks whenever you're running low.

But the low prices don't just stop at necessities. If you’re looking for the best deal on headphones, all you have to do is go to the electronics coupon page and it will bring up a deal on these COWIN E7 PRO noise-canceling headphones, which are now $80, thanks to a $10 coupon you could have missed.

Alternatively, if you are looking for deals on specific brands, you can search for their coupons from the page. So if you've had your eye on the Homall S-Racer gaming chair, you’ll find there's currently a coupon that saves you 5 percent, thanks to a simple search.

To discover all the deals you have been missing out on, head over to the Amazon Coupons page.

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How Do Astronauts Vote From Space?

Astronaut Kate Rubins casts her ballot from space.
Astronaut Kate Rubins casts her ballot from space.
NASA

Earlier this week, NASA announced that astronaut Kate Rubins had officially cast her vote from a makeshift voting booth aboard the International Space Station. As much as we’d like to believe her ballot came back to Earth in a tiny rocket, the actual transmission was much more mundane. Basically, it got sent to her county clerk as a PDF.

As NASA explains, voting from space begins the same way as voting abroad. Astronauts, like military members and other American citizens living overseas, must first submit a Federal Postcard Application (FPCA) to request an absentee ballot. Once approved, they can blast off knowing that their ballot will soon follow.

After the astronaut’s county clerk completes a practice round with folks at the Johnson Space Center in Houston, they can start the real voting process. The astronaut will then receive two electronic documents: a password-protected ballot sent by the Space Center’s mission control center, and an email with the password sent by the county clerk. The astronaut then “downlinks” (sends via satellite signal) their filled-out ballot back to the Space Center attendants, who forward it to the county clerk. Since the clerk needs a password to open the ballot, they’re the only other person who sees the astronaut’s responses. Then, as NPR reports, they copy the votes onto a regular paper ballot and submit it with the rest of them.

Though Americans have been visiting space for more than half a century, the early jaunts weren’t long enough to necessitate setting up a voting system from orbit. That changed in 1996, when John Blaha missed out on voting in the general election because his spaceflight to Russia’s space station Mir began in September—before absentee voters received their ballots—and he didn’t return until January 1997. So, as The Washington Post reports, NASA officials collaborated with Texas government officials to pass a law allowing astronauts to cast their ballots from space. In the fall of 1997, David Wolf became the first astronaut to submit his vote from a space station. The law is specific to Texas because most active astronauts reside there, but NASA has said that the process can be done from other states if need be.