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.

Helios Helium
16.05.1998

This image of the relatively quiet Sun was made using ultraviolet light emitted by ionized Helium atoms in the Solar chromosphere. Helium was first discovered in the Sun in 1868, its name fittingly derived from from the Greek word Helios, meaning Sun.

The Elephant s Trunk Nebula in Cepheus
19.01.2017

Like an illustration in a galactic Just So Story, the Elephant's Trunk Nebula winds through the emission nebula and young star cluster complex IC 1396, in the high and far off constellation of Cepheus. Also known as vdB 142, the cosmic elephant's trunk is over 20 light-years long.

Melotte 15 inthe Heart
10.02.2017

Cosmic clouds form fantastic shapes in the central regions of emission nebula IC 1805. The clouds are sculpted by stellar winds and radiation from massive hot stars in the nebula's newborn star cluster, Melotte 15.

Stellar Spectral Types: OBAFGKM
30.05.2001

Astronomers divide stars into different spectral types. First started in the 1800s, the spectral type was originally meant to classify the strength of hydrogen absorption lines. A few types that best describe the temperature of the star remain in use today.

Dark Spots on Neptune
21.08.2001

Neptune has spots. The Solar System's outermost gas giant shows a nearly uniform blue hue created by small amounts of methane drifting in a thick atmosphere of nearly colorless hydrogen and helium. Dark spots do appear, however, that are anti-cyclones: large high-pressure systems that swirl in Neptune's cold cloud tops.

Unusual Gas Filaments Surround Galaxy NGC 1275
25.07.2005

How were the unusual gas filaments surrounding galaxy NGC 1275 created? No one is sure. Galaxy NGC 1275 is the central dominant galaxy of the Perseus Cluster of Galaxies, a cluster with many member galaxies visible in the above image. In visible light, NGC 1275 appears to show a spectacular collision between two distinct galaxies.

Reflections on NGC 6188
1.06.2006

NGC 6188 is an interstellar carnival of young blue stars, hot red gas, and cool dark dust. Located 4,000 light years away in the disk of our Galaxy, NGC 6188 is home to the Ara OB1 association, a group of bright young stars whose nucleus forms the open cluster NGC 6193.

Barred Spiral Galaxy NGC 1672
18.04.2007

Many spiral galaxies have bars across their centers. Even our own Milky Way Galaxy is thought to have a modest central bar. Prominently barred spiral galaxy NGC 1672, pictured above, was captured in spectacular detail in this recently released image taken by the orbiting Hubble Space Telescope.

Simeis 188 in Stars, Dust and Gas
27.06.2012

When stars form, pandemonium reigns. A particularly colorful case is the star forming region Simeis 188 which houses an unusual and bright cloud arc cataloged as NGC 6559. Visible above are red glowing emission nebulas of hydrogen, blue reflection nebulas of dust, dark absorption nebulas of dust, and the stars that formed from them.