Zooming in on Star Cluster Terzan 5
24.03.2019

Globular clusters once ruled the Milky Way. Back in the old days, back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy. Today, there are less than 200 left. Over the eons, many globular clusters were destroyed by repeated fateful encounters with each other or the Galactic center.

The Horsehead Nebula in Infrared from Hubble
12.04.2020

While drifting through the cosmos, a magnificent interstellar dust cloud became sculpted by stellar winds and radiation to assume a recognizable shape. Fittingly named the Horsehead Nebula, it is embedded in the vast and complex Orion Nebula (M42).

Globular Cluster Omega Centauri
11.07.2024

Globular star cluster Omega Centauri packs about 10 million stars much older than the Sun into a volume some 150 light-years in diameter. Also known as NGC 5139, at a distance...

APOD: 2025 September 9 Б Up from the Earth: Gigantic Jet Lightning
9.09.2025

What's that rising up from the Earth? When circling the Earth on the International Space Station early in July, astronaut Nicole Ayers saw an unusual type of lightning rising up from the Earth: a gigantic jet. The powerful jet appears near the center of the featured image in red, white, and blue.

APOD: 2025 December 2 Б M77: Spiral Galaxy with an Active Center
2.12.2025

What's happening in the center of nearby spiral galaxy M77? The face-on galaxy lies a mere 47 million light-years away toward the constellation of the Sea Monster (Cetus). At that estimated distance, this gorgeous island universe is about 100 thousand light-years across.

Planetary Nebula Mz3: The Ant Nebula
5.02.2001

Why isn't this ant a big sphere? Planetary nebula Mz3 is being cast off by a star similar to our Sun that is, surely, round. Why then would the gas that is streaming away create an ant-shaped nebula that is distinctly not round?

Neptune's Great Dark Spot: Gone But Not Forgotten
1.12.2001

When NASA's Voyager 2 spacecraft flew by distant Neptune in August of 1989, astronomers were shocked. Since Neptune receives only 3 percent the sunlight Jupiter does, they expected to find a dormant, dark, frigid planet. Instead, the Voyager images revealed evidence of a dynamic and turbulent world.

M57: The Ring Nebula
22.03.2003

Except for the rings of Saturn, the Ring Nebula (M57) is probably the most famous celestial band. This planetary nebula's simple, graceful appearance is thought to be due to perspective -- our view from planet Earth looking straight into what is actually a barrel-shaped cloud of gas shrugged off by a dying central star.

NGC 3370: A Sharper View
11.09.2003

Similar in size and grand design to our own Milky Way, spiral galaxy NGC 3370 lies about 100 million light-years away toward the constellation Leo. Recorded here in exquisite detail by the Hubble Space...

Planetary Nebula Mz3: The Ant Nebula
1.05.2005

Why isn't this ant a big sphere? Planetary nebula Mz3 is being cast off by a star similar to our Sun that is, surely, round. Why then would the gas that is streaming away create an ant-shaped nebula that is distinctly not round?