APOD: 2025 May 5 Б Planet Lines Across Water
5.05.2025

WhatБs causing those lines? Objects in the sky sometimes appear reflected as lines across water Б but why? If the waterБs surface is smooth, then reflected objects would appear similarly -- as spots.

The Cat's Eye Nebula
28.06.1995

Three thousand light years away, a dying star throws off shells of glowing gas. This Hubble Space Telescope image reveals "The Cat's Eye Nebula" to be one of the most complex "planetary nebulae" known.

VLT: A New Largest Optical Telescope
1.09.1996

What is the largest telescope in the world? In the optical, this title was long held by the Hale 200-inch, and is presently held by the Keck telescopes in Hawaii. But an even larger optical telescope is being built.

Cold Wind From The Boomerang Nebula
15.10.1997

A cold wind blows from the central star of the Boomerang Nebula. Seen here in a false color image of dust reflected starlight, the nebula lies about 5,000 light-years away. The boomerang shaped...

Microlensing of the Einstein Cross
11.07.1995

The famous "Einstein Cross" is a case where a single object is seen four times. Here a very distant QSO happened to be placed right behind a massive galaxy. The gravitational effect...

Phoebe: Comet Moon of Saturn
30.06.2004

Was Saturn's moon Phoebe once a comet? Images from the robotic Cassini spacecraft taken two weeks ago when entering the neighborhood of Saturn indicate that Phoebe may have originated in the outer Solar System.

Pegasus dSph: Little Galaxy of the Local Group
22.01.1999

The Pegasus dwarf spheroidal galaxy (Peg dSph) is a small, newly recognized member of the Local Group of Galaxies. Likely a satellite companion of the Local Group's dominant player, the large spiral Andromeda (M31), the Pegasus dwarf galaxy is almost hidden in the glare of relatively bright foreground stars in our own Milkyway.

Saturns Moon Rhea from Cassini
15.02.2005

Each moon of Saturn seems to come with its own mystery. Rhea, Saturn's second largest moon behind Titan, shows unusual wisps, visible above as light colored streaks. Higher resolution images of the wisps show them to be made of long braided fractures.

The Eskimo Nebula from Hubble
9.07.2006

In 1787, astronomer William Herschel discovered the Eskimo Nebula. From the ground, NGC 2392 resembles a person's head surrounded by a parka hood. In 2000, the Hubble Space Telescope imaged the Eskimo Nebula. From space, the nebula displays gas clouds so complex they are not fully understood.

Mercury and the Chromosphere
10.11.2006

Enjoying Wednesday's transit of Mercury from Dallas, Texas, astronomer Phil Jones recorded this detailed image of the Sun. Along with a silhouette of the innermost planet, a network of cells and dark filaments can be seen against a bright solar disk with spicules and prominences along the Sun's edge.