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A new look at some fossilized footprints shows that more than one species of human was walking upright around 3.6 million years ago. (This story originally aired on ATC on Dec. 2, 2021.)

Scientists are tracking a deadly bird flu outbreak that has infected wild birds in more than 30 states. Purging the nation's poultry supply may not be enough to keep the virus from sticking around.

Scientists using the Hubble Space Telescope have spotted light from what appears to be the most distant star ever seen. It offers a glimpse into an early moment in the history of the universe.

How do boa constrictors breathe while constricting their victims? A new study finds that snakes can switch which set of ribs they use to draw in air as they crush their meal before devouring it.

Building and operating telescopes can generate a lot of greenhouse gases. In fact, it's as if each astronomer in the world was driving more than 100,000 miles per year, a new study finds.

Picture perfect: Mission managers say the telescope's mirror segments have been aligned and have focused on single stars, a critical milestone, and the telescope is working flawlessly.

The James Webb Space Telescope has seen its first starlight, but its 18 mirror segments aren't yet perfectly aligned. As a result, the pictures it's sending back now aren't exactly cosmic eye candy.

Common chemical elements are created in stars like our sun. But heavy elements, like iron, are thought to form in massive stars that explode and spew material — though it might be more complicated.

All chimps managed by the National Institutes of Health that are currently eligible to go to a sanctuary have been moved there, but animal welfare advocates say more should be allowed to go.

For infants, toddlers, and children, one sign of an especially close relationship is if two people do something that involves exchanging saliva, like taking bites from the same piece of food.

A new look at nearly 3.7 million-year-old fossil footprints uncovered in Tanzania shows that multiple species of early humans lived together at the same time.

Scientists have found many planets orbiting distant stars, but so far no proof that any have moons. Now, researchers have detected signs of a large exomoon orbiting a Jupiter-like world.

With the James Webb Space Telescope safely deployed, many scientists want to use it. To minimize the effect of unconscious biases, they go through a process developed for the Hubble Space Telescope.

The James Webb Space Telescope blasted off from French Guinea at 7:20 a.m. ET on Saturday, Dec. 25. The NASA mission was decades in the making and should reveal the earliest galaxies in the universe.

A study shows how much prey whales eat. It reveals how the global loss of whales changed ocean life in ways that may make it harder for them to rebound. (Story first aired on ATC on Nov. 11, 2021.)

NASA's James Webb Space Telescope is waiting at its launch site, after years of repeated delays and cost overruns. At one point, the giant new observatory was threatened with cancellation.

As they count down the hours to the highly anticipated launch of NASA's powerful, $10 billion James Webb Space Telescope, astronomers hope for the best while fearing the worst.

The upcoming launch of NASA's powerful James Webb Space Telescope should let astronomers see what some of the universe's first stars and galaxies looked like soon after the Big Bang.

The James Webb Space Telescope will let astronomers peer farther into space than ever before, to see what galaxies looked like when the universe was newly born.

NASA's TESS telescope finds a small, iron-rich planet which could help explain the origins of Mercury, the innermost planet in our solar system