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.

Moon Meets Mercury
9.05.2008

On Tuesday, May 6, while standing on planet Earth and sweeping your binoculars along the western horizon just after sunset, you might have encountered this arresting skyscape. The view features a slender crescent Moon and bright planet Mercury separated on the sky by only about 2 degrees.

Supernovae in the Whirlpool
11.06.2011

Where do spiral galaxies keep their supernovae? Near their massive star forming regions, of course, and those regions tend to lie along sweeping blue spiral arms. Because massive stars are very short-lived, they don't have a chance to wander far from their birth place.

Mu Cephei
11.10.2023

Mu Cephei is a very large star. An M-class supergiant some 1500 times the size of the Sun, it is one of the largest stars visible to the unaided eye, and even one of the largest in the entire Galaxy.

HD 82943: Planet Swallower
18.05.2001

Stars like HD 82943 are main sequence G dwarf stars with temperatures and compositions similar to the Sun. Also like the Sun, HD 82943 is known to have at least two giant planets, but unlike gas giants in our solar system their orbits are not nearly circular and bring them closer to the parent star.

M55 Color Magnitude Diagram
22.02.2001

This color "picture" of globular star cluster M55 may not look like any star cluster you've ever seen. Still, it shows a most fundamental view for students of stellar astronomy. In the picture...

APOD: 2023 October 10 Б Hidden Orion from Webb
9.10.2023

The Great Nebula in Orion has hidden stars. To the unaided eye in visible light, it appears as a small fuzzy patch in the constellation of Orion. But this image was taken by the Webb Space Telescope in a representative-color composite of red and very near infrared light.

T Pyxidis: Recurrent Nova
25.09.1997

What happens when a thermonuclear blast occurs on the surface of a white dwarf star? Over the years astronomers have watched (at a safe distance ...) as, 6,000 light years from Earth in the southern constellation Pyxis, a binary star known as T Pyxidis repeatedly produces these fearsome explosions.

Cabin Under the Stars
16.01.2019

Gocka's, a family nickname for the mountain cabin, and a wooden sled from a generation past stand quietly under the stars. The single exposure image was taken on January 6 from Tanndalen Sweden to evoke a simple visual experience of the dark mountain skies.

Nabta: Older than Stonehenge
8.04.1998

In the Sahara Desert in Egypt lie the oldest known astronomically aligned stones in the world: Nabta. Over one thousand years before the creation of Stonehenge, local herders built a stone circle and other structures on the shoreline of a lake that has long since dried up.