IC 4603: Reflection Nebula in Ophiuchius
4.06.2007

Why does this starfield photograph resemble an impressionistic painting? The effect is created not by digital trickery but by large amounts of interstellar dust. Dust, minute globs rich in carbon and similar in size to cigarette smoke, frequently starts in the outer atmospheres of large, cool, young stars.

Messier 101
15.04.2011

Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's famous catalog, but definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way galaxy.

The Whirlpool Galaxy and Beyond
5.09.2016

Follow the handle of the Big Dipper away from the dipper's bowl, until you get to the handle's last bright star. Then, just slide your telescope a little south and west and you might find this stunning pair of interacting galaxies, the 51st entry in Charles Messier's famous catalog.

Find the Moon
10.07.2021

Where's the Moon? Somewhere in this image, the Earth's Moon is hiding. The entire Moon is visible, in its completely full phase, in plain sight. Even the photographer's keen eye couldn...

APOD: 2025 May 21 Б International Space Station Crosses the Sun
20.05.2025

Typically, the International Space Station is visible only at night. Slowly drifting across the night sky as it orbits the Earth, the International Space Station (ISS) can be seen as a bright spot about once a month from many locations.

Shell Galaxies in Pisces
25.02.2011

This colorful cosmic skyscape features a peculiar system of galaxies cataloged as Arp 227 some 100 million light-years distant. Swimming within the boundaries of the constellation Pisces, Arp 227 consists of the two galaxies prominent on the left; the curious shell galaxy NGC 474 and its blue, spiral-armed neighbor NGC 470.

Moon and Planets Over Catalonia
29.02.2012

Venus and Jupiter will appear unusually close in the sky over the next month. The planetary conjunction will be easily visible to the unaided eye because Venus will appear brighter than any background star, and Jupiter will be nearly as bright. To see the near-alignment, simply look to the west after sunset.

A View Toward M101
19.05.2017

Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's famous catalog, but definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way galaxy.

The Aurora and the Sunrise
30.04.2018

On the International Space Station (ISS), you can only admire an aurora until the sun rises. Then the background Earth becomes too bright. Unfortunately, after sunset, the rapid orbit of the ISS around the Earth means that sunrise is usually less than 47 minutes away.

Comet 46P Wirtanen
14.11.2018

Periodic Comet 46P/Wirtanen is now the brightest comet in the night sky, but too faint to be seen by eye. From dark sky sites it could just become naked-eye visible though, as it's 5.4 year long looping orbit takes it closest to Earth and the Sun in mid December.