How many human cells does a pig need before it’s considered too human?

Putting pig organs in people is OK in the US, but growing human organs in pigs is not – why is that?

It’s normal for parents, or anyone, to have questions about vaccinations -- but what happens if your pediatrician urges a shot that’s under attack by the Trump administration?  The revolt by pediatricians, obstetricians, family physicians, infectious disease experts and internists came to a head when an advisory panel handpicked by Health Secretary Robert F. Kennedy Jr. urged an end to routine newborn vaccination against hepatitis B, a virus that can cause liver failure or liver cancer.

What are parents to do as doctors clash with Trump administration over vaccines?

Photos of the interstellar comet 3I/ATLAS show it traveling through our inner solar system. The growing collection of images has fostered intrigue around the mysterious object.

Interstellar comet 3I/ATLAS' journey through our solar system, in photos

Voyager 1, NASA’s deep-space probe, could soon become the first spacecraft to reach a historic milestone. In November 2026, the probe will be one light-day from Earth.

NASA's Voyager 1 set to achieve historic distance from Earth

The European Space Agency said that the black hole inside the spiral galaxy NGC 3783 has the mass of 30 million suns.

Astronomers detect black hole blasting winds at incredible speeds

Humanity's exploration of Mars should be organized around the search for signs of past or present Red Planet life, according to a new report from the U.S. National Academies.

1st human missions to Mars should hunt for signs of life, report says

A foot fossil found in Ethiopia belonged to an ancient human. The finding could knock one of the most famous names in human evolution from her spot on the family tree.

Foot fossil discovery could reshape human evolutionary history

…Except for Mab, which is even weirder than expected.

Uranus's small moons are dark, red, and water-poor

By Will Dunham WASHINGTON, Dec 8 (Reuters) - Scientists have observed the largest-known rotating structure in the cosmos - a gargantuan thread-like assemblage of hundreds of galaxies, gas and dark

Huge rotating structure of galaxies and dark matter is detected

Junk is accumulating in space at a fantastic pace, with millions of pieces orbiting the Earth, and humans need to figure out a way to deal with it.

Exploring ways to reduce the impact of space junk on Earth

New images taken by the Hubble Space Telescope and a Jupiter-bound mission showcase interstellar comet 3I/ATLAS ahead of its close pass by Earth.

New images reveal interstellar comet 3I/ATLAS approaching Earth

Rocket Lab will launch a Japanese technology-demonstrating satellite on Monday night (Dec. 8), and you can watch the action live.

Watch Rocket Lab launch Japanese technology-demonstrating satellite to orbit on Dec. 8

The waning moon shines close to the king of the planets on Dec. 7.

Don't miss Jupiter shining close to the waning gibbous moon on Dec. 7

On Episode 188 of This Week In Space, Rod Pyle and Tariq Malik discuss Jared Isaacman, the billionaire entrepreneur and private astronaut, who took had his second confirmation as NASA's next leader.

This Week In Space podcast: Episode 188 — A New NASA Leader Rises?

The Geminids return with near-perfect viewing conditions, offering skywatchers up to 150 meteors an hour under dark December skies.

Geminid meteor shower 2025 peaks next week. Here's what you need to know about this year's best meteor shower

Most astronauts who menstruate pause their cycle with hormones before hitting the stars, but in the future, we'll need more options.

Scientists sent a menstrual cup to space. This is how it went

Ever seen the northern lights? You have a magnetic layer in Earth’s atmosphere to thank for those beautiful displays. But the magnetosphere does a lot more than create auroras.

Earth’s magnetic field protects life on Earth from radiation, but it can move, and the magnetic poles can even flip

From bicycles to rockets, learning through experience – whether human or machine – is shaping the future of space exploration.

AI is making spacecraft propulsion more efficient – and could even lead to nuclear-powered rockets

Rocket Lab launched a satellite for a "confidential commercial customer" on Thursday morning (Nov. 20), just a few hours after giving notice of the impending liftoff.

Watch Rocket Lab launch Japanese technology-demonstrating satellite to orbit tonight

Newly arrived and soon-to-depart members of Expedition 73 prepared for what is to come next during this, their final week all together aboard the International Space Station.

3 astronauts settle into their new life in orbit | On the International Space Station this week Dec. 1-5, 2025

Errors don’t necessarily mean your mind is faulty. They may actually be a sign of a cognitive system with limited capacity working efficiently.

Misremembering might actually be a sign your memory is working optimally

Blue Origin's upcoming NS-37 space tourism launch has special significance: One of the passengers is Michi Benthaus, who will become the first wheelchair user in space.

Blue Origin's next space tourism flight will break new ground for people with disabilities

Conspiracy thinking, supernatural beliefs and pseudoscience can seem impervious to evidence. An anthropologist suggests the opposite: Extraordinary beliefs may be supported by an individual’s experience.

Flat Earth, spirits and conspiracy theories – experience can shape even extraordinary beliefs

A new view of Mars showcases a dramatic impact crater on the Red Planet with its debris wings unfurling across the surface like a butterfly in flight.

Mars orbiter sees 'butterfly' crater spread its wings on the Red Planet

By Will Dunham WASHINGTON, Dec 4 (Reuters) - Paleontologists for decades debated whether meat-eating dinosaur Nanotyrannus was actually just a juvenile Tyrannosaurus.

A throat bone settles it - Nanotyrannus was not a juvenile T. rex

A study suggests that a volcanic eruption around 1345 cooled the climate, leading to crop failures. On the ships that carried grain to fill the gap came plague-carrying fleas.

A volcanic eruption may have catalyzed the plague's arrival in Europe, study suggests

New data suggests an eruption cooled Europe, disrupted harvests and pushed Italian states into grain trades that may have begun one of history’s deadliest pandemics.

Science

1st human missions to Mars should hunt for signs of life, report says

Astronomers detect black hole blasting winds at incredible speeds

NASA's Voyager 1 set to achieve historic distance from Earth

Interstellar comet 3I/ATLAS' journey through our solar system, in photos

Putting pig organs in people is OK in the US, but growing human organs in pigs is not – why is that?

Putting pig organs in people is OK in the US, but growing human organs in pigs is not – why is that?

Foot fossil discovery could reshape human evolutionary history

Uranus's small moons are dark, red, and water-poor

Huge rotating structure of galaxies and dark matter is detected

Exploring ways to reduce the impact of space junk on Earth

New images reveal interstellar comet 3I/ATLAS approaching Earth

Watch Rocket Lab launch Japanese technology-demonstrating satellite to orbit on Dec. 8

Don't miss Jupiter shining close to the waning gibbous moon on Dec. 7

This Week In Space podcast: Episode 188 — A New NASA Leader Rises?

Geminid meteor shower 2025 peaks next week. Here's what you need to know about this year's best meteor shower

Scientists sent a menstrual cup to space. This is how it went

Earth’s magnetic field protects life on Earth from radiation, but it can move, and the magnetic poles can even flip

AI is making spacecraft propulsion more efficient – and could even lead to nuclear-powered rockets

Don't miss Jupiter shining close to the waning gibbous moon on Dec. 7

This Week In Space podcast: Episode 188 — A New NASA Leader Rises?

Watch Rocket Lab launch Japanese technology-demonstrating satellite to orbit tonight

3 astronauts settle into their new life in orbit | On the International Space Station this week Dec. 1-5, 2025

Misremembering might actually be a sign your memory is working optimally

Blue Origin's next space tourism flight will break new ground for people with disabilities

Misremembering might actually be a sign your memory is working optimally

Flat Earth, spirits and conspiracy theories – experience can shape even extraordinary beliefs

Mars orbiter sees 'butterfly' crater spread its wings on the Red Planet

A throat bone settles it - Nanotyrannus was not a juvenile T. rex

A volcanic eruption may have catalyzed the plague's arrival in Europe, study suggests

Volcanic eruption led to the Black Death, new research suggests

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