Astronomy Staff, Author at Astronomy.com | Page 6 of 278

LHC at CERN

Is there a hottest temperature possible in the universe?

Neutron stars are incredibly dense objects about 10 miles (16 km) across. Only their immense gravity keeps the matter inside from exploding; if you brought a spoonful of neutron star to Earth, the lack of gravity would cause it to expand rapidly.

Exotic Objects, Science

What would happen if a tablespoonful of a neutron star was brought to Earth?

galaxy cluster Abell 2744 as seen by JWST and the Chandra X-ray Observatory

Cosmology, Exotic Objects

Astronomers say they’ve spotted the oldest, most distant black hole. How do they know this?

Hubble image of variable star RS Puppis

How do Cepheid variables indicate distance?

Exotic Objects, Solar System

What are the chances of dark matter or a black hole ripping apart Earth?

The Moon rises over mountains in Utah. Credit: NASA/Bill Dunford.

Science, The Moon

Why does the Moon look so large sometimes as it rises on the horizon?

Telescopes and Equipment

See the hottest astronomy products of July

This artist’s concept shows what exoplanet K2-18b could look like based on science data. Credit: NASA, CSA, ESA, J. Olmsted (STScI), Science: N. Madhusudhan (Cambridge University).

Alien Life, Science

Did we find signs of life on K2-18 b? Not yet, but we might.

Artist's rendition of asteroid Psyche

Could Psyche be the core of the planetesimal that struck Earth and formed the Moon?

The expanding universe

How can the visible universe be 46 billion light-years in radius when the universe is only 13.8 billion years old?

The Sun rises at Stonehenge.

Observing, The Sun

Will the Sun always shine through Stonehenge on the solstice?

Merging black holes

When black holes merge, is the diameter of the new black hole bigger?