A Mercury Transit Music Video from SDO
21.10.2019

What's that small black dot moving across the Sun? Mercury. Possibly the clearest view of Mercury crossing in front of the Sun in 2016 May was from Earth orbit. The Solar Dynamics Observatory obtained an uninterrupted vista recording it not only in optical light but also in bands of ultraviolet light.

NGC 7331 Close Up
7.02.2020

Big, beautiful spiral galaxy NGC 7331 is often touted as an analog to our own Milky Way. About 50 million light-years distant in the northern constellation Pegasus, NGC 7331 was recognized early on as a spiral nebula and is actually one of the brighter galaxies not included in Charles Messier's famous 18th century catalog.

NGC 2359: Thor s Helmet
12.06.2020

NGC 2359 is a helmet-shaped cosmic cloud with wing-like appendages popularly called Thor's Helmet. Heroically sized even for a Norse god, Thor's Helmet is about 30 light-years across. In fact, the helmet...

M13: The Great Globular Cluster in Hercules
20.05.2021

In 1716, English astronomer Edmond Halley noted, "This is but a little Patch, but it shews itself to the naked Eye, when the Sky is serene and the Moon absent." Of course...

A Supercell Thunderstorm Over Texas
13.06.2021

Is that a cloud or an alien spaceship? It's an unusual and sometimes dangerous type of thunderstorm cloud called a supercell. Supercells may spawn damaging tornados, hail, downbursts of air, or drenching rain. Or they may just look impressive.

APOD: 2023 April 4 Б Olympus Mons: Largest Volcano in the Solar System
4.04.2023

The largest volcano in our Solar System is on Mars. Although three times higher than Earth's Mount Everest, Olympus Mons will not be difficult for humans to climb because of the volcano's shallow slopes and Mars' low gravity.

APOD: 2023 November 1 Б Annular Solar Eclipse over Utah
1.11.2023

Part of the Sun disappeared earlier this month, but few people were worried. The missing part, which included the center from some locations, just went behind the Moon in what is known as an annular solar eclipse. Featured here is an eclipse sequence taken as the Moon was overtaking the rising Sun in the sky.

APOD: 2024 September 24 Б NGC 6727: The Rampaging Baboon Nebula
24.09.2024

This dusty region is forming stars. Part of a sprawling molecular cloud complex that resembles, to some, a rampaging baboon, the region is a relatively close by 500 light-years away toward the constellation Corona Australis. That's about one third the distance of the more famous stellar nursery known as the Orion Nebula.

APOD: 2025 March 16 Б Venus and the Triply Ultraviolet Sun
16.03.2025

This was a very unusual type of solar eclipse. Typically, it is the Earth's Moon that eclipses the Sun. In 2012, though, the planet Venus took a turn. Like a solar eclipse by the Moon, the phase of Venus became a continually thinner crescent as Venus became increasingly better aligned with the Sun.

APOD: 2026 April 20 Б Comet R3 PanSTARRS over a Himalayan Valley
20.04.2026

The best way to see comet R3 PanSTARRSБs long tail is with a camera. This week, the recently brightened comet appears in northern skies to the east just before dawn, but is only barely visible to the unaided eye.