Comet Lovejoy over The Great Wall
20.02.2014

Fading now as it returns to the outer solar system Comet Lovejoy (C/2013 R1) still graces planet Earth's sky, a delicate apparition in binoculars or small telescopes. The comet, a relic...

M31: The Andromeda Galaxy
30.07.2014

Andromeda is the nearest major galaxy to our own Milky Way Galaxy. Our Galaxy is thought to look much like Andromeda. Together these two galaxies dominate the Local Group of galaxies. The diffuse light from Andromeda is caused by the hundreds of billions of stars that compose it.

The Old Moon in the Young Moon s Arms
10.11.2018

Tonight the Moon is young again, but this stunning image of a young Moon near the western horizon was taken just after sunset on October 10. On the lunar disk Earthshine, earthlight reflected from the Moon's night side, is embraced by the slim, sunlit crescent just over 2 days old.

NGC 4676: The Mighty Mice
14.06.2019

These two mighty galaxies are pulling each other apart. Known as The Mice because they have such long tails, each large spiral galaxy has actually passed through the other. Their long tails are drawn out by strong gravitational tides rather than collisions of their individual stars.

Perihelion to Aphelion
8.07.2021

Aphelion for 2021 occurred on July 5th. That's the point in Earth's elliptical orbit when it is farthest from the Sun. Of course, the distance from the Sun doesn't determine the seasons.

APOD: 2025 August 7 Б The Double Cluster in Perseus
7.08.2025

This stunning starfield spans about three full moons (1.5 degrees) across the heroic northern constellation of Perseus. It holds the famous pair of open star clusters, h and Chi Persei. Also cataloged...

Cepheus 1: Nearby Galaxy Hiding
1.12.1998

Some galaxies are hard to find. Besides being hidden behind the dust and bright foreground stars of our Milky Way Galaxy, recently discovered Cepheus 1 was missed previously because it is so uniformly dim.

M100: A Grand Design
3.02.2001

Majestic on a truly cosmic scale, M100 is appropriately known as a Grand Design spiral galaxy. A large galaxy of over 100 billion or so stars with well defined spiral arms, it is similar to our own Milky Way.

Antares and Rho Ophiuchi
22.09.1997

Why is the sky near Antares and Rho Ophiuchi so colorful? The colors result from a mixture of objects and processes. Fine dust illuminated from the front by starlight produces blue reflection nebulae. Gaseous clouds whose atoms are excited by ultraviolet starlight produce reddish emission nebulae. Backlit dust clouds block starlight and so appear dark.

Spiral Sunspot
4.02.1999

Spiral galaxies abound in the universe, but spiral sunspots are definitely an unusual twist. This distinctive spiral-shaped sunspot caught the attention of National Solar Observatory astronomers and was photographed on February 19, 1982 with the Vacuum Solar Telescope on Kitt Peak.