Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to ...

Two studies fill in gaps about the cosmos’s ordinary matter. One maps it all, even the “missing matter.” The other details one of its hiding spots.

All told, gas within galaxies and clusters accounts for perhaps half of all of the normal, non-dark matter expected to be present in the Universe. NASA/CXC/Univ. of Bonn/K. Migkas et al.

A team of astronomers have put together the largest, most detailed map of the universe ever created – and you can explore it ...

NASA's newest astrophysics space telescope launched in March on a mission to create an all-sky map of the universe. Now ...

The universe was very small in the distant past, it underwent a rapid expansion, and in the course of that expansion, the universe cooled down and allowed matter to coalesce into stars and galaxies.

There’s an idea that suggests all the universe’s electrons are actually one particle forever traveling backwards and forwards in time. It’s a simple, elegant idea that solves some of physics ...

“Your kingdom is a kingdom of all universes” (Psalms 145:13). Song of Songs 6:8 references “worlds without number.” Talmud says G-d oversees “18,000 universes” ( Avodah Zarah 3b ).