Observations show the universe appears flat, yet its true size and global shape beyond the observable horizon may remain forever unknown.

In this video, we explore the vastness of the universe and attempt to quantify its size. We delve into the concepts of cosmic measurements, the observable universe, and the theories that explain the ...

We know how the universe began. An event we call the Big Bang started it all about 13.8 billion years ago. How the universe ends, though, is an open question. The path forward depends on the ...

Andromeda and the Milky Way merge. NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas; and A. Mellinger Share Curious Kids is a series for children of all ages. If you have a question you’d ...

“The cosmos is also within us, we're made of star-stuff. We are a way for the cosmos to know itself.” - Carl Sagan Compared to the Sun, how big is the Earth? What is a scale model and how does it help ...

For centuries, people have looked to the stars, asking how it all began—and how it might end. Now, thanks to a bold new study by physicists from Cornell University, Shanghai Jiao Tong University, and ...