A Year of Resolving Backgrounds
30.12.2000

No matter which direction you look, no matter what type of light you see, the sky glows - but why? The sources of many of these background radiations have remained long-standing puzzles, but this millennial year brought some partial resolutions.

Hitomi Launches
18.02.2016

On February 17 at 5:45pm JST this H-IIA rocket blasted skyward from JAXA's Tanegashima Space Center located off the southern coast of Japan, planet Earth. Onboard was the ASTRO-H X-ray astronomy satellite, now in orbit.

Loop I in the Northern Sky
3.05.1999

One of the largest coherent structures on the sky is known simply as Loop I and can best be seen in radio and X-ray maps. Spanning over 100 degrees, part of Loop I appears so prominent in northern sky maps that it is known as the North Polar Spur (NPS).

Sigmoids Predict Solar Eruptions
16.03.1999

On the Sun, S marks the spot. Solar explosions have been discovered to explode preferentially from regions marked with this letter. The surface of the quiet Sun is a maze of hot gas and flowing magnetic fields. When two regions of high magnetic field strength approach each other, they typically pass uneventfully.

NGC 1569: Heavy Elements from a Small Galaxy
25.07.2002

For astronomers, elements other than hydrogen and helium are sometimes considered to be simply "heavy elements". It's understandable really, because even lumped all together heavy elements make up an exceedingly small fraction of the Universe. Still, heavy elements can profoundly influence galaxy and star formation ... not to mention the formation of planets and people.

Wind from a Black Hole
1.07.2006

Binary star system GRO J1655-40 consists of a relatively normal star about twice as massive as the Sun co-orbiting with a black hole of about seven solar masses. This striking artist's vision of the exotic binary system helps visualize matter drawn from the normal star by gravity and swirling toward the black hole.

Pulsar Wind in the Vela Nebula
19.07.2001

The Vela pulsar was born 10,000 years ago at the center of a supernova -- an exploding star. In this Chandra Observatory x-ray image, the pulsar still produces a glowing nebula at the heart of the expanding cloud of stellar debris.

N44C: A Nebular Mystery
14.05.2002

Why is N44C glowing so strangely? The star that appears to powers the nebula, although young and bright, does not seem hot enough to create some of the colors observed. A search for a hidden hotter star in X-rays has come up empty.

The Swarm
28.01.2005

What do you call a group of black holes ... a flock, a brace, a swarm? Monitoring a region around the center of our Galaxy, astronomers have indeed found evidence for a surprisingly large number...

A High Energy Fleet
25.02.1996

Looking like a fleet of futuristic starcruisers poised over planet Earth, NASA's highly successful series of High Energy Astrophysical Observatory (HEAO) spacecraft appear above in a vintage illustration. Labeled A, B, and C in this conceptual picture, the spacebased telescopes were known as HEAO-1, HEAO-2, and HEAO-3 respectively.