In the Center of the Omega Nebula
6.05.2012

In the depths of the dark clouds of dust and molecular gas known as the Omega Nebula, stars continue to form. The above image from the Hubble Space Telescope's Advanced Camera for Surveys shows exquisite detail in the famous star-forming region.

Henrietta Leavitt Calibrates the Stars
27.10.1998

Humanity's understanding of the relative brightness and variability of stars was revolutionized by the work of Henrietta Swan Leavitt (1868-1921). Working at Harvard College Observatory, Leavitt precisely calibrated the photographic magnitudes of 47 stars to which all other stars could be compared.

Mars and the Beehive
10.06.2023

This month, bright Mars and brilliant Venus are the prominent celestial beacons in planet Earth's western skies after sunset. Wandering through the constellation Cancer the Crab, the Red Planet was captured here on the evening of June 3 near the stars of open cluster Messier 44.

VB 10: A Large Planet Orbiting a Small Star
3.06.2009

Can a planet be as large as the star that it orbits? Recent observations have discovered that nearby Van Biesbroeck's star might have just such a large planet. Although VB 10 lies only...

Nebulosity in Sagittarius
10.08.1997

What causes the colors in this beautiful nebulosity in Sagittarius? Dubbed NGC 6589 and NGC 6590, the colors of this nebulosity, are caused by gas and dust. The blue color of the nebula nearest the bright stars is caused by reflection off interstellar dust.

Moon, Venus, and Planet Earth
19.09.2013

In this engaging scene from planet Earth, the Moon shines through cloudy skies following sunset on the evening of September 8. Despite the fading light, the camera's long exposure still recorded a colorful, detailed view of a shoreline and western horizon looking toward the island San Gabriel from Colonia del Sacramento, Uruguay.

APOD: 2026 March 11 Б CG 4: The Globule and the Galaxy
11.03.2026

Is this a cosmic monster ready to devour an unsuspecting galaxy? Thankfully, that is not the case. The red БmonsterБ shown in the featured image is Cometary Globule CG 4, 1,300 light-years away in the Constellation Puppis.

APOD: 2024 January 29 Б The Pleiades: Seven Dusty Sisters
29.01.2024

The well-known Pleiades star cluster is slowly destroying part of a passing cloud of gas and dust. The Pleiades is the brightest open cluster of stars on Earth's sky and can be seen from almost any northerly location with the unaided eye.

Two Million Stars on the Move
17.04.2017

If you could watch the night sky for one million years -- how would it change? Besides local effects caused by the Earth's spin and the reorientation of the Earth's spin axis, the stars themselves will move.

NGC 3603: X-Rays From A Starburst Cluster
24.01.2001

A mere 20,000 light-years from the Sun lies the NGC 3603 star cluster, a resident of the nearby Carina spiral arm of our Milky Way galaxy. Seen here in this recent false-color x-ray...