Technologies

NASA’s Hubble telescope helps scientists solve mystery of dead galaxies

Why did some galaxies from the early universe suddenly stop making stars? Astronomers look back in time to find out.

As mere mortals, we yearn to travel back in time — an obsession nourished by iconic contraptions such as Marty McFly’s car, Hermione Granger’s time turner and Doctor Who’s police box. Often forgotten, however, are the real-life astronomers who kind of already do it.

Recently, one such research team tapped time travel to solve a space mystery from billions of years ago using a unique combination of super sensitive telescopes: Why did some of the early universe’s galaxies strangely stop popping out stars and become inactive, or quiescent?

Galaxies are thought to be at the pinnacle of their star manufacturing potential at this moment in time, so it’s especially puzzling when we discover any that are dormant. Right now, they should be making more stars than ever.

«The most massive galaxies in our universe formed incredibly early, just after the Big Bang happened,» Kate Whitaker, a professor of astronomy at University of Massachusetts-Amherst and lead author of a new study, said in a statement. «But for some reason, they have shut down. They’re no longer forming new stars.»

It turns out, some old galaxies merely ran low on star fuel, or cold gas, early on in their lifetimes. The results of the group’s study were published Wednesday in the journal Nature and could rewrite our knowledge of how the universe evolved.

But hold on, you’re probably still on that bit about astronomers going back in time. If they can swing that, why didn’t they show up to Stephen Hawking’s famous time-traveler-only dinner party?

You might have heard the term «light-year,» which refers to the distance light whizzes along in one Earth year. We need this term as a measurement because light doesn’t travel instantaneously. Of course, turning on your bedroom lamp leads to near-immediate brightness, but if someone turned on a flashlight while standing on the moon, about 238,900 miles (384,472 kilometers) away, its beam wouldn’t reach us for over a second.

That means moonlight has about a one-second lag for us Earthlings. In effect, when we glance at the moon, we’re seeing everything one second after it happens. We’re sort of looking back in time.

Astronomers scale that concept up by the billions. Using powerful telescopes as time machines, they look into deep space — like, billions of light-years away. For this study that mined the mystery of prematurely «dying» galaxies, for instance, the team looked at six cosmic bodies 10 billion to 12 billion light-years away in the universe.

So, it took 10 billion to 12 billion years for any illumination within the studied area to reach their telescope lenses. That means the astronomers were looking back in time far enough to watch the moments soon after the Big Bang — which occurred about 14 billion years ago — unfold in real-time.

Lo and behold, that’s how they solved the cosmic puzzle. The researchers say the galaxies either burned through their cold gas supply too quickly or are blocked from replenishment.

More specifically, Whitaker and fellow researchers demystified the issue by using a mixture of powerful telescopes: the Hubble Space Telescope and the Atacama Large Millimeter/submillimeter Array, or ALMA. The Hubble Space Telescope is sensitive to light across the spectrum — even the type humans can’t see.

And as if time travel wasn’t fantastical enough, the team took advantage of another tool called gravitational lensing to enhance the light collected. Basically, the lens’ viewpoint traveled along a line decorated by hundreds of other galaxy clusters.

Gravitational pulls of those galaxies were strong enough to warp beams of light coming from the team’s six galaxies of interest, stretching them while they traveled to Earth. That helped shed light — no pun intended — on juicy details that would have otherwise been missed within the galaxies.

ALMA, on the other hand, used those details to look for levels of the cold gas, or star fuel, needed by galaxies to make stellar bodies. «There was copious cold gas in the early universe, so these galaxies, from 12 billion years ago, should have plenty left in the fuel tank,» Whitaker said.

Now we know — thanks to the closest we’ve come to time travel — those tanks have been empty.

Technologies

Today’s NYT Mini Crossword Answers for Saturday, Sept. 6

Here are the answers for The New York Times Mini Crossword for Sept. 6.

Looking for the most recent Mini Crossword answer? Click here for today’s Mini Crossword hints, as well as our daily answers and hints for The New York Times Wordle, Strands, Connections and Connections: Sports Edition puzzles.

Today’s Mini Crossword is extra-long, as usual on Saturdays. And a couple of the clues were stumpers! Need answers? Read on. And if you could use some hints and guidance for daily solving, check out our Mini Crossword tips.

If you’re looking for today’s Wordle, Connections, Connections: Sports Edition and Strands answers, you can visit CNET’s NYT puzzle hints page.

Read more: Tips and Tricks for Solving The New York Times Mini Crossword

Let’s get to those Mini Crossword clues and answers.

Mini across clues and answers

1A clue: U.S. prez who served four terms
Answer: FDR

4A clue: Hurry, in Shakespearean English
Answer: HIE

7A clue: Only country to have a musical instrument (the harp) as its national emblem
Answer: IRELAND

9A clue: Big name in rum
Answer: BACARDI

10A clue: She holds the record for most #1 Billboard hits by a female rapper (5)
Answer: CARDIB

11A clue: Ancient time-tracking device
Answer: SUNDIAL

12A clue: Ctrl-___-Del
Answer: ALT

13A clue: Opposite of SSW
Answer: NNE

14A clue: Used to be
Answer: WAS

15A clue: Jupiter or Saturn, primarily
Answer: GAS

Mini down clues and answers

1D clue: Small lie
Answer: FIB

2D clue: Whom Count von Count of «Sesame Street» is a parody of
Answer: DRACULA

3D clue: Takes back, as testimony
Answer: RECANTS

4D clue: 1920s U.S. president
Answer: HARDING

5D clue: Home to the W.N.B.A.’s Fever
Answer: INDIANA

6D clue: Weed gummies
Answer: EDIBLES

8D clue: Cooking grease
Answer: LARD

11D clue: Observed
Answer: SAW

Technologies

Researchers Discover 18 Popular VPNs Are Connected: Why This Matters

All are owned by 3 separate groups but CNET’s recommended VPNs are not on the list

Virtual private networks are popular ways to keep your online activity private and hide your physical location from your internet service provider and apps. But it’s obviously important to choose a safe and secure VPN.

Three university researchers have discovered that 18 of the most widely used VPNs have shared infrastructures with serious security flaws that could expose customers’ browsing activity and leave their systems vulnerable to corrupted data. These VPNs are among the top 100 most popular on the Google Play Store, comprising more than 700 million downloads.

Read more: Best VPN Service for 2025: Our Top Picks in a Tight Race

The peer-reviewed study by the Privacy Enhancing Technologies Symposium found that these VPNs, despite calling themselves independent businesses, are actually grouped into three separate families of companies.

None of CNET’s recommended VPNs — ExpressVPN, NordVPN, Surfshark, Proton VPN and Mullvad — are on the list. (If you currently don’t have a VPN, here’s why you might want to start using one.)

According to the findings, these are the three groups that contain the 18 VPNs:

Family A: Turbo VPN, Turbo VPN Lite, VPN Monster, VPN Proxy Master, VPN Proxy Master Lite, Robot VPN, Snap VPN and SuperNet VPN
Family B: Global VPN, Inf VPN, Melon VPN, Super Z VPN, Touch VPN, VPN ProMaster, XY VPN and 3X VPN
Family C: X-VPN and Fast Potato VPN

Researchers determined that the VPNs in Family A are shared between three providers linked to Qihoo 360, a firm identified by the US Department of Defense as a Chinese military company. The VPNs in Family B use the same IP addresses from the same hosting company.

Know your VPN’s parent company

It’s a cautionary tale about why it’s important to know who’s behind the VPN you’re using, says CNET senior writer Attila Tomaschek.

«It’s also crucial to know what kinds of data the VPN provider is sharing with its parent company and affiliated entities,» Tomaschek said. «Some of these companies may even be compelled to log customer activity and share it with authorities, depending on the jurisdiction in which they operate.»

Despite the warnings, Tomaschek says it’s not so easy to figure out who controls your VPN. But he says there are measures that customers can take.

«Users can do a few things to help ensure the VPN they’re using is reputable,» Tomaschek says. «Check the privacy policy — specifically for terms like ‘logging,’ ‘data sharing’ or ‘data collection.’ A Google search of the provider can help determine whether the VPN has been involved in questionable activity. Read detailed, unbiased reviews from reputable sources. Be especially wary of signing on with a free VPN, even if it’s listed as a top choice in your app store.»

The PETS researchers examined the most downloaded VPNs on Android, looking for overlaps among business paperwork, web presence and codebase. After identifying code similarities, they were able to group the 18 VPNs into three groups. The study was initially spurred by VPN Pro’s own findings, «Who owns your VPN? 105 VPNs run by just 24 companies.»

CNET’s Tomaschek has advice for anyone who has been using one of these 18 VPNs.

«I’d recommend deleting it from your device immediately,» he said. «If you suspect that any sensitive personal data may have been compromised, it’s a good idea to keep an eye on your credit report and look into services like dark web monitoring or identity theft protection.»

Technologies

Today’s NYT Connections: Sports Edition Hints and Answers for Sept. 6, #348

Here are hints and the answers for the NYT Connections: Sports Edition puzzle for Sept. 6, No. 348.

Looking for the most recent regular Connections answers? Click here for today’s Connections hints, as well as our daily answers and hints for The New York Times Mini Crossword, Wordle and Strands puzzles.

Today’s Connections: Sports Edition was a stumper. But if you play cards, the green group is a fun one for sure. If you’re struggling but still want to solve it, read on for hints and the answers.

Connections: Sports Edition is published by The Athletic, the subscription-based sports journalism site owned by the Times. It doesn’t show up in the NYT Games app but appears in The Athletic’s own app. Or you can play it for free online.

Read more: NYT Connections: Sports Edition Puzzle Comes Out of Beta

Hints for today’s Connections: Sports Edition groups

Here are four hints for the groupings in today’s Connections: Sports Edition puzzle, ranked from the easiest yellow group to the tough (and sometimes bizarre) purple group.

Yellow group hint: Racket time.

Green group hint: Ante up!

Blue group hint: NY signal-callers.

Purple group hint: Coach’s CV.