Mercury is up before sunrise and visible until mid-June

Watch for Mercury before sunup, the bright planet Jupiter will be nearby. Mercury reaches greatest elongation on May 29. It's best from the Southern Hemisphere.

How is stellar magnitude used in astronomy?

The brightest stars to the eye are 1st magnitude, and dimmest stars to the eye are 6th magnitude. How does stellar magnitude work in astronomy?

What’s a safe distance from a supernova for Earth?

What's a safe distance from a supernova? To survive a supernova, recent data says Earth would have to be at least 160 light-years away from the exploding star.

Visible planets and night sky for May and June 2023

May's visible planets: Brilliant Venus and Mars are in the western evening sky. Morning planets are Saturn, Jupiter and Mercury.

How many red dwarf stars in nearby space?

Astronomer Guy Ottewell uses 2 charts - showing 2 different volumes of space - to contemplate and question the density of red dwarf stars in our Milky Way.

Sky measurements: Degrees, arcminutes and arcseconds

What are sky measurements - or distances - in the night sky? Here's what it means for objects to be several degrees (or arcminutes or arcseconds) apart.

Meteor shower guide: Next up the daytime the Arietids

The daytime Arietid meteor shower is in early June, followed by the Delta Aquariids starting in late July. Your 2023 meteor shower guide here.

A deep penumbral lunar eclipse overnight tonight

A penumbral lunar eclipse happens tonight, May 5-6, 2023. It's visible from eastern Europe, Africa, Asia, Australia, New Zealand, Antarctica and Indonesia.

A penumbral eclipse of the moon is subtle

There are 3 kinds of lunar eclipses: total, partial and penumbral. A penumbral eclipse is very subtle. You can notice a shading on the moon's face.

Mars in 2023: Still bright in May and June

Mars is still bright, but it's destined to fade in brightness and appear for fewer hours each night. See Mars while you can! Charts for May and June 2023 here.