Three Tails of Comet NEOWISE
8.03.2021

What created the unusual red tail in Comet NEOWISE? Sodium. A spectacular sight back in the summer of 2020, Comet NEOWISE, at times, displayed something more than just a surprisingly striated white dust tail and a pleasingly patchy blue ion tail.

APOD: 2025 August 13 Б Trapezium: In the Heart of Orion
13.08.2025

What lies in the heart of Orion? Trapezium: four bright stars, that can be found near the center of this sharp cosmic portrait. Gathered within a region about 1.5 light-years in radius, these stars dominate the core of the dense Orion Nebula Star Cluster.

NGC 7023: The Iris Nebula
14.12.2001

Like delicate cosmic petals, these clouds of interstellar dust and gas have blossomed 1,300 light-years away in the fertile star fields of the constellation Cepheus. Sometimes called the Iris Nebula and dutifully cataloged as NGC 7023, this is not the only nebula in the sky to evoke the imagery of flowers.

Jovian Aurora
23.01.1998

These two recently released Hubble Space Telescope close-ups show the Northern and Southern lights ... on Jupiter. Like aurora on Earth, these Jovian aurora are caused by charged particles funneled into the atmosphere above the planet's North (right) and South poles by magnetic fields.

Clouds of Perseus
21.10.2011

Cosmic clouds of gas and dust drift across this magnificent panorama, spanning some 17 degrees near the southern boundary of the heroic constellation Perseus. The collaborative skyscape begins with bluish stars of Perseus at the left, but the eye is drawn to the striking, red NGC 1499.

The Ghosts of Cassiopeia
25.10.2019

These bright rims and flowing shapes look ghostly on a cosmic scale. A telescopic view toward the constellation Cassiopeia, the colorful skyscape features swept-back, comet-shaped clouds IC 59 (left) and IC 63. About 600 light-years distant, the clouds aren't actually ghosts.

M27: Not A Comet
9.10.1998

While searching the skies above 18th century France for comets, astronomer Charles Messier diligently recorded this object as number 27 on his list of things which are definitely not comets. So what is it?

XMM Launched
21.12.1999

X-ray astronomy entered a golden age earlier this month with the successful launch of the X-ray Multi-Mirror (XMM) satellite. XMM's three huge telescope barrels each hold 58 concentric cylindrical mirrors, together totaling a surface area rivaling a tennis court.

NGC 6914 Nebulae
4.03.2011

A dramatic study in contrasts, this colorful skyscape features stars, dust, and glowing gas in NGC 6914. The complex of nebulae lies some 6,000 light-years away, toward the high-flying northern constellation Cygnus and the plane of our Milky Way Galaxy.

NGC 6302: The Butterfly Nebula
2.03.2019

The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects. Though its wingspan covers over 3 light-years, NGC 6302 is no exception. With an estimated surface...