Meteor before Galaxy
7.08.2022

What's that green streak in front of the Andromeda galaxy? A meteor. While photographing the Andromeda galaxy in 2016, near the peak of the Perseid Meteor Shower, a small pebble from deep space crossed right in front of our Milky Way Galaxy's far-distant companion.

AR 9169: A Large Sunspot
25.09.2000

One of the largest sunspots in recent years is now crossing our Sun. Dominating active region AR 9169, the sunspot is the large dark complex visible below (west) and right of center in the above photograph of our Sun taken last Thursday.

The Bubble Nebula
4.08.2012

Blown by the wind from a massive star, this interstellar apparition has a surprisingly familiar shape. Cataloged as NGC 7635, it is also known simply as The Bubble Nebula. Although it looks delicate, the 10 light-year diameter bubble offers evidence of violent processes at work.

The Large Cloud of Magellan
5.09.2019

The 16th century Portuguese navigator Ferdinand Magellan and his crew had plenty of time to study the southern sky during the first circumnavigation of planet Earth. As a result, two fuzzy cloud-like objects easily...

The Largest Rock in our Solar System
1.01.2023

There, that dot on the right, that's the largest rock known in our Solar System. It is larger than every known asteroid, moon, and comet nucleus. It is larger than any other local rocky planet.

APOD: 2025 November 10 Б Micro Moon vs Super Moon
10.11.2025

What was so super about Wednesday's supermoon? Last week, a full moon occurred that appeared slightly larger and brighter than usual. The reason is that the Moon's fully illuminated phase occurred within a short time from perigee - when the Moon was its closest to the Earth in its elliptical orbit.

Shocked by Supernova 1987A
23.02.2002

Fifteen years ago today, the brightest supernova of modern times was sighted. Over time, astronomers have watched and waited for the expanding debris from this tremendous stellar explosion to crash into previously expelled material.

A Higher Dimensional Universe
18.04.2001

Does our universe have higher but unusual spatial dimensions? This idea has been gaining popularity to help explain why vastly separated parts of our universe appear so similar, and why the geometry of our universe does not seem to result naturally from the amounts of matter it

Cassini Flyby
26.08.1999

Connect the dots and you'll trace the path of the Cassini spacecraft as it took a final turn by Earth on its way to the outer solar system. The dots (in a horizontal row just below center) are actually successive images of the spacecraft.

Approaching the Bubble Nebula
31.05.2017

What would it look like to approach the Bubble Nebula? Blown by the wind and radiation from a massive star, this bubble now spans seven light-years in diameter. The hot star inside is thousands of times more luminous than our Sun, and is now offset from the nebula's center.