The universe created in the big bang was predominantly made of hydrogen - about 75% by mass; the remainder of the matter was in the form of helium with some small traces of other light el...

(Written by Christine Pulliam, Smithsonian Astrophysical Observatory, for Science at the Smithsonian, a website featuring highlights of scientific research at the Smithsonian Institution....

A Rydberg atom is one with an electron that spends most of its time far from the nucleus. Rydberg atoms, which are normally artificially produced, can have dimensions thousands of times...

Cambridge, MA Astronomers announced today that the first Pan-STARRS (Panoramic Survey Telescope & Rapid Response System) telescope, PS1, is fully operational. This innovative facilit...

CH Cyg is a binary star system containing a white dwarf that feeds from the wind of a red giant star. The material from the wind forms a hot accretion disk around the white dwarf before c...

Io is one of the four moons of Jupiter that Galileo discovered after he turned his new telescope heavenward. They shocked him and his contemporaries because they demonstrated that heavenl...

Bok globules are small interstellar clouds of very cold gas and dust that are so thick they are nearly totally opaque to visible light, although they can be studied with infrared and radi...

Have you ever wondered how we find alien worlds? Whether E.T life exists? What happens if you fall into a black hole? CfA astronomers give their thoughts on these questions and more at th...

A Cepheid star is one whose mass and age results in physical conditions that generate periodic oscillations in its photosphere. A Cepheid thus varies regularly in brightness, with a peri...

Miami, FL For over 10 years, NASA's Chandra X-ray Observatory has repeatedly observed the Andromeda Galaxy for a combined total of nearly one million seconds. This unique data set has gi...