Stellar Spectral Types: OBAFGKM
18.04.2004

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.

Central Cygnus Skyscape
18.08.2015

In cosmic brush strokes of glowing hydrogen gas, this beautiful skyscape unfolds across the plane of our Milky Way Galaxy and the center of the northern constellation Cygnus the Swan. The featured image spans about six degrees.

The Elephants Trunk in IC 1396
12.10.2015

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. Of course, the cosmic elephant's trunk is over 20 light-years long.

M82: Galaxy with a Supergalactic Wind
20.02.2016

What's lighting up the Cigar Galaxy? M82, as this irregular galaxy is also known, was stirred up by a recent pass near large spiral galaxy M81. This doesn't fully explain the source of the red-glowing outwardly expanding gas, however.

The North America and Pelican Nebulas
13.06.2016

Here lie familiar shapes in unfamiliar locations. On the left is an emission nebula cataloged as NGC 7000, famous partly because it resembles our fair planet's continent of North America. The emission region to the right of the North America Nebula is IC 5070, also known for its suggestive outlines as the Pelican Nebula.

The Tulip in the Swan
19.10.2016

Framing a bright emission region this telescopic view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation Cygnus the Swan. Popularly called the Tulip Nebula, the glowing cloud of interstellar gas and dust is also found in the 1959 catalog by astronomer Stewart Sharpless as Sh2-101.

APOD: 2024 April 28 Б Rings Around the Ring Nebula
27.04.2024

The Ring Nebula (M57) is more complicated than it appears through a small telescope. The easily visible central ring is about one light-year across, but this remarkably deep exposure - a collaborative effort combining data from three different large telescopes - explores the looping filaments of glowing gas extending much farther from the nebula's central star.

APOD: 2024 October 22 Б M16: Pillars of Star Creation
21.10.2024

These dark pillars may look destructive, but they are creating stars. This pillar-capturing picture of the Eagle Nebula combines visible light exposures taken with the Hubble Space Telescope with infrared images taken with the James Webb Space Telescope to highlight evaporating gaseous globules (EGGs) emerging from pillars of molecular hydrogen gas and dust.

At the Edge of the Helix Nebula
12.05.2002

While exploring the inner edge of the Helix Nebula with the Hubble Space Telescope's Wide Field Planetary Camera 2, astronomers were able to produce this striking image - rich in details of an exotic environment.

MyCn18: An Hourglass Nebula
17.01.1996

The sands of time are running out for the central star of this hourglass-shaped planetary nebula. With its nuclear fuel exhausted, this brief, spectacular, closing phase of a Sun-like star's life occurs as its outer layers are ejected - its core becoming a cooling, fading White Dwarf.