Galaxies

An exoplanet has been discovered orbiting a star of extragalactic origin that contains far less metal than models predict for stars with planets. Christopher Intagliata reports

An analysis of public data from a NASA satellite turns up massive, previously unseen galactic structures

Even in the best-case scenario, the future of the James Webb Space Telescope now looks worse than before

Massive galaxies acting as lenses have revealed five ancient galaxies behind the lensing galaxies. Hundreds more old galaxies should be discovered this way. Steve Mirsky reports

A shadow cosmos, woven silently into our own, may have its own rich inner life

A galaxy that existed just 600 million years after the big bang is the most distant object ever seen

Two recent papers have proposed possible "first cores"--short-lived objects that give rise to protostars

A laboratory experiment may have offered the first glimpses of a long-predicted quantum effect known as Hawking radiation

A new type of supernova is forcing astronomers to rethink the lives of the biggest stars

NASA is building an innovative and risky space telescope that promises to surpass the hugely successful Hubble. Here's an exclusive, behind-the-scenes look at the most audacious space project in decades

The Harvard College Observatory archive holds half a million glass plates recording a century's worth of observations covering the entire night sky