M55 Color Magnitude Diagram
23.02.2001

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...

The Colors and Magnitudes of M13
13.06.2019

M13 is modestly recognized as the Great Globular Star Cluster in Hercules. A ball of stars numbering in the hundreds of thousands crowded into a region 150 light years across, it lies some 25,000 light-years away. The sharp, color picture of M13 at upper left is familiar to many telescopic imagers.

Introducing Comet Garradd
27.07.2011

Another large snowball is falling toward the Sun. Comet Garradd was discovered two years ago by Gordon Garradd in Australia, and is currently visible through a small telescope at visual magnitude nine. Officially designated...

Solar Flares Cause Sun Quakes
1.06.1998

An 11th magnitude quake has been recorded on the Sun, immediately following a moderate solar flare. The quake was the first ever recorded on the Sun, but only because astronomers have only recently figured out when and how to find them using the orbiting SOHO spacecraft.

Comet Williams in 1998
6.10.1998

The brightest comet in the sky right now is Comet Williams. Moving slowly though the constellation of Centaurus, Comet Williams, at magnitude 8, is visible to Southern Hemisphere observers with binoculars. In ten days...

Saturn and ISS
9.07.2022

Soaring high in skies around planet Earth, bright planet Saturn was a star of June's morning planet parade. But very briefly on June 24 it posed with a bright object in low Earth orbit, the International Space Station.

The Sloan Digital Sky Survey Telescope
17.06.1998

The Sloan Digital Sky Survey (SDSS) will soon begin. Pictured above is the 2.5-meter telescope poised to create the most ambitious sky map in the history of astronomy. SDSS will catalog one quarter of the sky down past 23rd magnitude ( R), obtaining redshifts for galaxies and quasars brighter than magnitude 19.

Iridium 52: Not A Meteor
22.10.1999

While hunting for meteors in the night sky above the White Mountains near Bishop, California, astrophotographer James Young instead captured this brilliant celestial apparition. Recorded near twilight on August 13, the bright streak is not the flash of a meteor trail but sunlight glinting from a satellite.

APOD: 2004 August 30- Announcing Comet C 2003 K4 LINEAR
30.08.2004

A comet discovered last year has brightened unexpectedly and now may become visible to the unaided eye within the next month. Designated Comet C/2003 K4 (LINEAR), the comet was discovered in 2003 May by project LINEAR.

The Tails of Comet NEAT Q4
12.05.2004

Comet NEAT (Q4) is showing its tails. As the large snowball officially dubbed Comet C/2001 Q4 (NEAT) falls toward the inner Solar System, it has already passed the Earth and will reach its closest approach to the Sun this coming Saturday.