A Close Encounter Of The Stellar Kind
7.07.2001

The unassuming star centered in this sky view will one day be our next door stellar neighbor. The faint 9th magnitude red dwarf, currently 63 light-years away in the constellation Ophiucus, was recently discovered to be approaching our Solar System.

The Belt of Venus Over Mercedes Argentina
7.02.2012

Although you've surely seen it, you might not have noticed it. During a cloudless twilight, just before sunrise or after sunset, part of the atmosphere above the horizon appears slightly off-color, slightly pink or orange.

Milky Way and Exploding Meteor
12.08.2015

Tonight the Perseid Meteor Shower reaches its maximum. Grains of icy rock will streak across the sky as they evaporate during entry into Earth's atmosphere. These grains were shed from Comet Swift-Tuttle.

The Annotated Galactic Center
27.09.2019

The center of our Milky Way galaxy can be found some 26,000 light-years away toward the constellation Sagittarius. Even on a dark night, you can't really see it though. Gaze in that direction, and your sight-line is quickly obscured by intervening interstellar dust.

10 Days of Venus and Jupiter
4.03.2023

Venus and Jupiter may have caught your attention lately. The impending close conjunction of the two brightest planets visible in clear evening skies has been hard to miss. With Jupiter at the top, starting...

APOD: 2025 September 30 Б Comet Lemmon Brightens
30.09.2025

Comet Lemmon is brightening and moving into morning northern skies. Besides Comet SWAN25B and Comet ATLAS, Comet C/2025 A6 (Lemmon) is now the third comet currently visible with binoculars and on long camera exposures. Comet Lemmon was discovered early this year and is still headed into the inner Solar System.

A Perseid Meteor
11.08.2002

The ongoing Perseid Meteor Shower should be at its strongest on August 12 and 13. The best time to watch will be between 2:00 AM and dawn on Monday morning (so plan on setting your alarm tonight!) and then again on Tuesday.

The Milky Road
20.10.2007

Inspired during a visit to Fort Davis, Texas, home of McDonald Observatory and dark night skies, photographer Larry Landolfi created this tantalizing fantasy view. The composited image suggests the Milky Way is a heavenly extension of a deserted country road.

Red Aurora Over Australia
1.02.2012

Why would the sky glow red? Aurora. Last week's solar storms, emanating mostly from active sunspot region 1402, showered particles on the Earth that excited oxygen atoms high in the Earth's atmosphere. As the excited element's electrons fell back to their ground state, they emitted a red glow.

Circling a Black Hole at its Photon Sphere
2.07.2013

What would it look like to go right up to a black hole? One particularly interesting place near a black hole is its photon sphere, where photons can orbit in circles, a sphere 50 percent further out than the event horizon.