If not in visible stars and galaxies, the most likely hiding place for the matter is in the dark space between galaxies.

A thin shell of air wraps around Earth, stretching about 20 miles above the surface. This invisible veil is packed with tiny molecules that sustain life. Just beyond this fragile layer lies the ...

Using a powerful combination of space-based measurements and Subaru’s advanced imaging, astronomers have discovered two rare companions, one of which enables a key test for NASA’s Roman Space ...

Simulation studies indicate water formation within the first 200 million years of the universe, primarily through supernovae from the first generation of stars. Pair-instability supernovae, occurring ...

In a young galaxy more than 13 billion light-years away, the James Webb Space Telescope has picked up a chemical fingerprint ...

On April 24, 1990, all 24,000 pounds of the Hubble Space Telescope were tucked away inside the Discovery space shuttle when it launched into space. Thirty-five years later, NASA says Hubble has proven ...

Still, science being science, we needed proof—and we got it in 1992, when two astronomers found two planets orbiting a pulsar ...

A surprisingly mature spiral galaxy named Alaknanda has been spotted just 1.5 billion years after the Big Bang—far earlier ...

Calculating the total mass of the universe is not simple, because most of the mass is invisible. In a pie chart of the contents of the universe, only 5 percent is normal matter, atoms that make up all ...

A spiral galaxy, shaped much like our Milky Way, has been found in an era when astronomers believed such well-formed galaxies ...