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

Sora Video Limits Got You Down? Pay Up for More, Says OpenAI

Sora has opened to everyone in the US, and OpenAI is now charging for extra AI video generations.

Soon after Sora dropped its invite-only requirement, OpenAI is already moving to monetize the popular AI video social media app. The company has introduced paid «video generation packs,» allowing you to purchase additional AI-generated videos after reaching the daily free limit.

Until now, you could generate around 30 videos a day for free or up to 100 for Pro accounts. Now, anyone who hits that cap will see a prompt to purchase extra «gens» through the App Store.

A small bundle of 10 extra generations costs roughly $4, according to Sora’s listing on Apple App Store, but OpenAI’s support page states that the exact credits used per video range based on factors like the video length and resolution.

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OpenAI’s Bill Peebles confirmed the change in a post on X, citing increased demand and «unsustainable» economics as reasons behind the change. He also confirms the free quota options are likely temporary.

«Eventually, we will need to bring the free gens down to accommodate growth (we won’t have enough GPUs to do it otherwise!), but we’ll be transparent as it happens,» he wrote. «[i]n the meantime, enjoy the crazy usage limits.»

Technologies

You Can Nab the Apple Watch SE 3 for a Record-Low $200 if You Act Fast

Amazon just knocked $49 off this budget-friendly wearable for the first time since its release.

Released alongside the Series 11 and Ultra 3, the Apple Watch SE 3 is the latest budget-friendly model in Apple’s lineup. Starting at $249, it already saves you $150 compared to the Series 11, and right now you can pick it up for even less.

Amazon is offering the biggest (and practically only) discount we’ve seen since this smartwatch hit shelves, knocking it down to a record-low $200. That’s a $49 discount, but it only applies to the starlight color. We also don’t expect this deal to last long, so be sure to get your order in soon.

Even at full price, CNET smartwatch expert Vanessa Hand Orellana called the third-gen SE a «$250 steal that delivers nearly everything you’d want from a wearable, with surprisingly few compromises.» It’s equipped with the same S10 processor as the Series 11 and Ultra 3, and offers many of the same features, like fast charging, 5G connectivity and new wellness tools. Plus, the vibrant 40mm display is always on, so you can check the time with a glance. Other helpful features include onboard Siri, fall detection and a durable design that’s water-resistant up to 50 meters.

SMARTWATCH DEALS OF THE WEEK

Apple Watch Series 10 (GPS, 46mm, Black, M/L Sports Band):

$329 (save $100)
Samsung Galaxy Watch 7 (Bluetooth, 40mm, Cream):

$200 (save $100)
Amazfit Active 42mm Smartwatch With 14 Day Battery Life (Black):

$85 (save $25)
Garmin Vivoactive 5 GPS Smartwatch With AMOLED Display:

$200 (save $100)
Samsung Galaxy Watch Ultra (Wi-Fi, LTE, 47mm, Titanium Silver):

$500 (save $150)

Deals are selected by the CNET Group commerce team, and may be unrelated to this article.

Why this deal matters

Deals on the latest Apple tech are far and few between, which makes this Apple Watch SE 3 discount a welcome surprise. You can pick it up for a record-low $200 right now at Amazon, which is just half the price of the flagship Series 11. If you prefer a larger display, the 44mm model is also $49 off, dropping the price to $230.

You can also find plenty of other bargains on the latest and previous-gen models in our full roundup of all the best Apple Watch deals.

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Technologies

Surprise Twist: Apple’s Next iPhones Might Come in These 3 Unlikely Colors

Apple seems to be choosing a deep, earthy path for its upcoming phone colors.

From cosmic orange to coffee brown? Brown, purple and burgundy will be the available colors for the iPhone 18 Pro next September, if a leak out of China proves true.

Depending on your language translator, brown could mean simply «brown» or «coffee brown,» but you get the general idea. The tidbit comes from regular leaker Digital Chat Station’s post on the Chinese microblogging platform Weibo. The post also says that black will not be an available color for the iPhone 18 Pro.

A representative for Apple did not immediately respond to a request for comment.

The iPhone 17 Pro comes in cosmic orange, deep blue and silver.

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The Apple release schedule for the iPhone 18 series has been shifting, but the latest intel reports that the iPhone 18 Pro, iPhone 18 Pro Max and iPhone Fold will launch in September 2026. The iPhone 18 and iPhone 18e will follow in the spring of 2027.

If Digital Chat Station’s leak is accurate, the iPhone 18 Pro would be the first Pro edition in years without a color resembling black, white or silver.

Here are the colors for the iPhone Pro dating back to its introduction in 2019:

2019: iPhone 11 Pro/Pro Max: Midnight Green, Space Gray, Silver, Gold
2020: iPhone 12 Pro/Pro Max: Graphite, Silver, Gold, Pacific Blue
2021: iPhone 13 Pro/13 Pro Max: Graphite, Gold, Silver, Sierra Blue, Alpine Green (March 2022)
2022: iPhone 14 Pro/14 Pro Max: Space Black, Silver, Gold, Deep Purple
2023: iPhone 15 Pro/15 Pro Max: Black Titanium, White Titanium, Blue Titanium, Natural Titanium
2024: iPhone 16 Pro/16 Pro Max: Black Titanium, Natural Titanium, White Titanium, Desert Titanium
2025: iPhone 17 Pro/17 Pro Max: Cosmic Orange, Deep Blue, Silver

Not offering any version of black for Pro models might seem counterintuitive, since the iPhone 16 Pro Max black titanium version has been a big seller, and black has also been popular with iPhone 17 shoppers. But a lack of black has not hurt iPhone 17 Pro sales.