All of Mercury
28.04.2019

Only six years ago, the entire surface of planet Mercury was finally mapped. Detailed observations of the innermost planet's surprising crust began when the robotic have been ongoing since the robotic MESSENGER spacecraft first passed Mercury in 2008 and continued until its controlled crash landing in 2015.

Dark Matter in a Simulated Universe
25.10.2020

Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast, why galaxies orbit clusters...

Spiral Galaxy NGC 1512: The Inner Rings
8.05.2022

Most galaxies don't have any rings -- why does this galaxy have two? To begin, the bright band near NGC 1512's center is a nuclear ring, a ring that surrounds the galaxy center and glows brightly with recently formed stars.

Waves of the Great Lacerta Nebula
14.09.2022

It is one of the largest nebulas on the sky -- why isn't it better known? Roughly the same angular size as the Andromeda Galaxy, the Great Lacerta Nebula can be found toward the constellation of the Lizard (Lacerta).

Encke and the Tadpoles
27.10.2023

History's second known periodic comet is Comet Encke (2P/Encke). As it swings through the inner Solar System, Encke's orbit takes it from an aphelion, its greatest distance from the Sun, inside the orbit of Jupiter to a perihelion just inside the orbit of Mercury.

APOD: 2024 April 1 Б Swirling Magnetic Field around Our Galaxys Central Black Hole
1.04.2024

What's happening to the big black hole in the center of our galaxy? It is sucking in matter from a swirling disk -- a disk that is magnetized, it has now been confirmed. Specifically, the black hole's accretion disk has recently been seen to emit polarized light, radiation frequently associated with a magnetized source.

Shell Game in NGC 300
22.08.2002

Featured in color in yesterday's episode, big, beautiful, face-on spiral galaxy NGC 300 is seen here through a narrow filter that transmits only the red light of hydrogen atoms. Ionized by energetic starlight, a hydrogen atom emits the characteristic red H-alpha light as its single electron is recaptured and transitions to lower energy states.

Hale-Bopp on Schedule
25.07.1996

Late March and early April of 1996 marked a banner season for viewing the spectacular naked-eye comet Hyakutake. The spring of 1997 could well offer a similar cometary wonder, Comet Hale-Bopp. Discovered last year while approaching the inner solar sytem Hale-Bopp has been eagerly watched for signs that it will indeed brighten spectacularly.

The Heart in NGC 346
14.02.2003

Yes, it's Valentine's Day (!) and looking toward star cluster NGC 346 in our neighboring galaxy the Small Magellanic Cloud, astronomers have noted this heart-shaped cloud of hot, x-ray emitting gas in the cluster's central region.

Redshift 10: Evidence for a New Farthest Galaxy
17.03.2004

What's the farthest galaxy known? The answer keeps changing as astronomers compete to find galaxies that top the list. The new claimed record holder is now the faint smudge indicated in the above images by an 8.2-meter Very Large Telescope (VLT) operating in Chile.