galaxies

A new image looks at the mysterious Cartwheel Galaxy, some 500 million light years from Earth.
New estimate puts the number at 1 trillion to 2 trillion.
Dragonfly 44 could help solve one of nature's biggest mysteries.
Astronomer Tabetha Boyajian aims to learn the truth about her namesake sun.
The plot covers 650 billion cubic light-years and contains 1.2 million galaxies.
Astronomers have spotted a brilliant "fireworks" display millions of light years away.