Magazine

Solar System

Does a comet’s period change because it loses mass every time it nears the Sun?

Deep-Sky Objects

Observe the dark side of the famous Orion Nebula

Observing

How does adaptive optics work?

Planets

See mighty Mars at opposition

Deep-Sky Objects

Explore the constellation Cassiopeia

Solar System

Where is the solar system heading?

Solar System

Does Planet Nine exist?

Telescopes and Equipment

Could the Seestar S50 be your first imaging telescope?

Human Spaceflight

How Artemis will land humans on the Moon

Observing

January 2025: What’s in the Southern Hemisphere sky this month?

Observing

January 2025: What’s in the sky this month? The Moon occults Mars and the Pleiades, plus Mars reaches opposition

Robotic Spaceflight, Solar System

How do spacecraft avoid collisions in the asteroid belt?