Light Echoes from V838 Mon
27.03.2003

Nominated for most mysterious star in the Milky Way, V838 Monocerotis briefly became one of the brightest stars in our galaxy. Its outburst discovered in January 2002, observations have indicated that V838 Mon somehow...

Two Views, Two Crescents
11.11.2010

Venus rose in a glowing dawn sky on November 5th, just before the Sun. For early morning risers, its brilliant crescent phase was best appreciated with binoculars or a small telescope. On that...

APOD: 2026 March 11 Б CG 4: The Globule and the Galaxy
11.03.2026

Is this a cosmic monster ready to devour an unsuspecting galaxy? Thankfully, that is not the case. The red БmonsterБ shown in the featured image is Cometary Globule CG 4, 1,300 light-years away in the Constellation Puppis.

Doomed Star Eta Carinae
11.06.1996

Eta Carinae may be about to explode. But no one knows when - it may be next year, it may be one million years from now. Eta Carinae's mass - about 100 times greater than our Sun - make it an excellent candidate for a full blown supernova.

Geminid Meteors over Chile
8.12.2019

Are meteors streaming out from a point in the sky? Yes, in a way. When the Earth crosses a stream of Sun-orbiting meteors, these meteors appear to come from the direction of the stream -- with the directional point called the radiant.

Betelgeuse Imagined
1.01.2020

Why is Betelgeuse fading? No one knows. Betelgeuse, one of the brightest and most recognized stars in the night sky, is only half as bright as it used to be only five months ago.

Vega and Comet 12P Pons-Brooks
8.12.2023

On December 4, periodic Comet 12P/Pons-Brooks shared this telescopic field of view with Vega, alpha star of the northern constellation Lyra. Fifth brightest star in planet Earth's night, Vega is some 25 light-years distant while the much fainter comet was about 21 light-minutes away.

Light Can Twist as Well as Spin
19.11.2003

Light is more complicated than we thought. When astronomers measure light, they are usually concerned with its direction, energy, and spin polarization (sometimes). Recently, however, it has been more broadly realized that photons...

Star Clusters Young and Old
10.09.2006

Many stars form in clusters. Galactic or open star clusters are relatively young swarms of bright stars born together near the plane of our Milky Way Galaxy. Separated by about a degree...

CoRoT Satellite Discovers Rocky Planet
23.09.2009

How similar is exoplanet CoRoT-7b to Earth? The newly discovered extra-solar planet is the closest physical match yet, with a mass about five Earths and a radius of about 1.7 Earths. Also, the home star to CoRoT-7b, although 500 light years distant, is very similar to our Sun.