The Download: NASA’s nuclear spacecraft and unveiling our AI 10

This is today's edition of The Download, our weekday newsletter that provides a daily dose of what's going on in the world of technology.

NASA is building the first nuclear reactor-powered interplanetary spacecraft. How will it work?

Just before Artemis II began its historic slingshot around the moon, NASA revealed an even grander space travel plan. By the end of 2028, the agency aims to fly a nuclear reactor-powered interplanetary spacecraft to Mars.

A successful mission would herald a new era in spaceflight-and might just give the US the edge in the race against China. But the projectremainsshrouded in mystery.

MIT Technology Reviewpicked the brains of nuclear power and propulsion experts to find out how the nuclear-powered spacecraft might work.Here's what we discovered.

-Robin George Andrews

Thisstoryis part of MIT Technology Review Explains, our series untangling the complex, messy world of technology to help you understandwhat'scoming next.You can read more from the series here.

Coming soon: our 10 Things That Matter in AI Right Now

Each year, we compile our 10 Breakthrough Technologies list, featuring our educated predictions for which technologies will change the world.Our 2026 list, however, was harder to wrangle than normal. Why? We hadso manyworthy AI candidates wecouldn'tfit them all in!

That got us thinking: what if we made an entirely new list all about AI? Before we knew it, we had the beginnings of whatwe'recalling 10 Things That Matter in AI Right Now.

On April 21,we'llunveil the list on stage at our signature AI conference,EmTechAI, and then publish it online later that day. If you want to be among the first to see it,join us at EmTech AIorbecome a subscriberto livestream the announcement.

Find out more about the list's methodology and aims here.

-Niall Firth & Amy Nordrum

MIT Technology Review Narrated: this company is developing gene therapies for muscle growth, erectile dysfunction, and radical longevity"

In January, a handful of volunteers were injected with two experimental gene therapies as part of an unusual clinical trial. Its long-term goal? To achieve radical human life extension.

The therapies are designed to support muscle growth. The company behind them, Unlimited Bio, also plans to trial similar therapies in the scalp (for baldness) and penis (for erectile dysfunction). But some experts are concerned about the plans.

Find out why the trial has divided opinion.

-JessicaHamzelou

This is our lateststoryto be turned into an MIT Technology Review Narrated podcast, which we publish each week onSpotifyandApple Podcasts. Just navigate to MIT Technology Review Narrated on either platform,andfollow us to get all ournew contentasit'sreleased.

The must-reads

I'vecombed the internet to find you today's most fun/important/scary/fascinating stories about technology.

1 Google, Microsoft, and Meta track users even when they opt out
According to an independent audit, they may be racking up billions in fines. (404 Media)
+ How our digital devices put our privacy at risk.(Ars Technica)
+ Privacy's next frontier is AI memories."(MIT Technology Review)

2 OpenAI has a new cybersecurity model-and strategy
GPT-5.4-Cyber is designed specifically for defensive cybersecurity work. (Reuters$)
+ OpenAI has joined Anthropic in focusing on cybersecurity recently.(Wired$)
+ LikeAnthopic, its latest model is only available to verified testers.(NYT$)
+ AI is already making online crimes easier. It could get much worse.(MIT Technology Review)

3 Amazon is buying satellite firm Globalstar in a bid to rival Starlink
The $11.6 billion deal targets the lucrativesatellite internet market.(WSJ$)
+ Apple has chosen Amazon satellites for iPhone.(Ars Technica)

4 Whatit'sliketolive with an experimental brain implant
Early BCI users explain what the technology gives-and takes. (IEEE)
+ A patient with Neuralink got a boost from generative AI.(MIT Technology Review)

5DozensofAI disease-prediction models were trained on dubious data
A few might already have been used on patients. (Nature)

6 Uber is breaking from its gig economy model to avoid robotaxi disruption
It's spending $10 billion to buy thousands of autonomous vehicles.(FT$)

7xAIis being sued over datacenterpollution
Musk's AI venture stands accused by the NAACP of violating the Clean Air Act. (Engadget)
+ No one wants a datacenterin their backyard.(MIT Technology Review)

8 Apple could win the AI race without running
It may reap the rewards of everyone else's spending. (Axios)

9 How 4chan set a precedent for AI's reasoning abilities
The notorious forum tested a feature called chain of thought."(The Atlantic$)

10 The surprising emotional toll of wearing Meta's AI sunglasses
Their shortcomings are making users sad. (NYT$)

Quote of the day

Everything got a whole lot worse once they rolled out AI."

-A copywritertellsthe Guardianthatthey'redrowning in workslop" - AI-generated work that seems polished buthasmajorflaws

One More Thing

GETTY IMAGESHow refrigeration ruined fresh food

Bananas may not be chilled in the grocery store, butthey'rethe ultimate refrigerated fruit.It'sonly thanks to a network of thermal control thatthey'vebecome a global commodity. And that salad bag on the shelf?It'snot just a bag but a highly engineered respiratory apparatus.

According to Nicola Twilley-a contributor to the New Yorker and cohost of the podcast Gastropod-refrigeration has wrecked our food system. Thankfully, there are promising alternative preservation methods.

Read the full story on her research.

-AllisonArieff

We can still havenice things

A place for comfort, fun and distraction to brighten up your day. (Got any ideas?Drop me a line.)

+ Spotify only shows 10 popular songs per artist.This toollists them all.
+ These GIF animationsare mesmerizing loops of nostalgia.
+ This site beautifully visualizes Curiosity's 13 yearson Mars.
+ A retro-futurist designer has turneda NES consoleinto a workingsynthesizer.