Excuses for Missing Dark Matter

Astronomers display creativity at rationalizing their inability to find what they believe makes up the bulk of the universe.

Solar System Theories Challenged

"Everything we know about the formation of solar systems might be wrong," say two astronomers who discovered something "very bizarre."

Globular Clusters Give Astronomers Cluster Headaches

The old story is out, and nobody knows what the new story should be.

Young Galaxy Mature for Its Age

Remote galaxy that should be young looks well-behaved and mature, "truly surprising" astronomers.

Observations Upset Models of Stellar Evolution

Stellar evolution models go back decades. Ever since the Hertzsprung-Russell diagram came out in 1910 (graphing temperature against luminosity), showing most stars fell on a line called the “main sequence”, astrophysicists have sought to understand the life cycle of stars from birth to death. In general, the story goes, collapsing clouds of gas and dust produce main-sequence stars that burn nuclear fuel till they run out. Depending on their masses, they end up as supernovae, red giants or slowly-cooling cinders. While red dwarfs cool down slowly into the darkness, supernovae and red giants eject mass outward into space . Two new planets found close to a red giant are among new headaches for theorists.