Unexpected X Rays from Perseus Galaxy Cluster
1.01.2018

Why does the Perseus galaxy cluster shine so strangely in one specific color of X-rays? No one is sure, but a much-debated hypothesis holds that these X-rays are a clue to the long-sought identity of dark matter.

Huge Void Implicated in Distant Universe
27.08.2007

What has created this huge empty area in the universe? No one is yet sure, and even the extent of the estimated billion-light year void is being researched. The void is not a hole...

APOD: 2020 August 31 Б SS 433: Binary Star Micro Quasar
30.08.2020

SS 433 is one of the most exotic star systems known. Its unremarkable name stems from its inclusion in a catalog of Milky Way stars which emit radiation characteristic of atomic hydrogen. Its remarkable behavior stems from a compact object, a black hole or neutron star, which has produced an accretion disk with jets.

NGC 1365: Barred Spiral Galaxy
8.10.1999

NGC 1365 is a giant barred spiral galaxy about 200,000 light-years in diameter and 60 million light-years distant in the southern constellation Fornax. These three recently released images offer views of this majestic island universe in visible and infrared light.

Why is QSO 1229+204 so Bright?
24.08.1996

What causes the center of this barred spiral galaxy to light up brighter than almost anything in the universe? The quasar there is a good fraction of the way across our observable universe...

The Heart Of NGC 4261
19.10.1997

What evil lurks in the hearts of galaxies? This Hubble Space Telescope picture of the center of the nearby elliptical galaxy NGC 4261 tells one dramatic tale. The gas and dust in this disk are swirling into what is almost certainly a massive black hole.

Jet Near Light Speed
23.11.1997

Einstein's Special Theory of Relativity says that nothing can travel faster than the speed of light. Jets of protons and electrons that shoot away from objects such as quasars and black holes appear to travel at speeds approaching this maximum speed, though. Such jets carry tremendous energy and can ram straight through interstellar material.

Spiral Galaxy NGC 3628 Edge On
31.10.1996

This is what a spiral galaxy looks like sideways. This view of NGC 3628 nearly resembles our own Milky Way Galaxy, which is also known to be a spiral. The dark band across the center is absorbed starlight caused by the galaxy's own interstellar dust.

The Center of NGC 6251 is Glowing
12.09.1997

Something is lighting up the center of galaxy NGC 6251. Leading speculation holds that it is a large black hole not shrouded by gas and dust typically found near the center of a galaxy.

Quasar in an Elliptical Galaxy
9.04.1998

Where do quasars live? Quasars are the brightest objects in the universe, so bright they can be seen from across the universe. Observations continue to show that most quasars are surrounded by a relatively faint nebulous patch. Astronomers are trying to identify the nature of these patches.