Expansive Comet Holmes
20.11.2007

The spherical coma of Comet Holmes has swollen to a diameter of over 1.4 million kilometers, making the tenuous, dusty cloud even bigger than the Sun. Scattering sunlight, all that dust and gas came...

The Eclipse Tree
24.12.2000

If you look closely at the shadow of this tree, you will see something quite unusual: it is composed of hundreds of images of a partially eclipsed Sun. Early today, trees across North America will be casting similar shadows as a partial eclipse of the Sun takes place.

Molecular Torus Surrounds Black Hole
8.09.2004

Why do some black hole surroundings appear brighter than others? In the centers of active galaxies, supermassive black holes at least thousands of times the mass of our Sun dominate. Many, called Seyfert Type I, are very bright in visible light. Others, called Seyfert Type II, are rather dim.

Comet C 2017 K2 (PanSTARRS)
29.06.2022

Imaged on June 20 2022, comet C/2017 K2 (PanSTARRS) shares this wide telescopic field of view with open star cluster IC 4665 and bright star Beta Ophiuchi, near a starry edge of the Milky Way.

APM 08279+5255: The Brightest Object Yet Known
18.08.1998

It shines with the brightness of 100 billion Suns. Is it a mirage? The recently discovered quasar labeled APM 08279+5255 has set a new record as being the brightest continuously emitting object yet known.

An Etruscan Vase Moon Rising
22.02.2009

What's happened to the Moon? Nothing, although from some locations, February's full moon, which occurred about two weeks ago, appeared strangely distorted as it rose. Visible in particular was a curiously inverted...

Pixels in the Sun
25.06.2021

These two panels, composed of video frames made with a safe solar telescope and hydrogen alpha filter, show remarkably sharp details on the solar disk and giant prominences along the Sun's edge on June 6 (top) and June 18.

Eclipse In The Shade
13.08.1999

Near the shadow of the moon under a shady tree, dozens of images of a 1994 solar eclipse in progress are visible in this striking picture from the campus of Northwestern University in Evanston, Illinois. What creates the multiple images?

The 37 Cluster
13.05.2024

For the mostly harmless denizens of planet Earth, the brighter stars of open cluster NGC 2169 seem to form a cosmic 37. Did you expect 42? From our perspective, the improbable numerical asterism appears solely by chance. It lies at an estimated distance of 3,300 light-years toward the constellation Orion.

A Solar Filament Erupts
15.09.2018

What's happened to our Sun? Nothing very unusual -- it just threw a filament. Toward the middle of 2012, a long standing solar filament suddenly erupted into space producing an energetic Coronal Mass Ejection (CME).