APOD: 2023 January 17 Б Unexpected Clouds Toward the Andromeda Galaxy
16.01.2023

Why are there oxygen-emitting arcs near the direction of the Andromeda galaxy? No one is sure. The gas arcs, shown in blue, were discovered and first confirmed by amateur astronomers just last year.

Comet PanSTARRS in the Southern Fish
16.06.2016

Now approaching our fair planet this Comet PanSTARRS (C/2013 X1) will come closest on June 21-22, a mere 5.3 light-minutes away. By then its appearance low in northern hemisphere predawn skies (high in the south), will be affected by the light of a nearly Full Moon, though.

Dark Markings of the Sky
25.04.2009

Based on wide field photographs, American astronomer Edward Emerson Barnard cataloged the dark markings of the sky in the early 20th century. Barnard's markings are dark nebulae, interstellar clouds of obscuring gas and dust.

Asteroid 2005 YU55 Passes the Earth
9.11.2011

Asteroid 2005 YU55 passed by the Earth yesterday, posing no danger. The space rock, estimated to be about 400 meters across, coasted by just inside the orbit of Earth's Moon. Although the passing...

Lovejoy in the New Year
3.01.2014

A rival to vanquished Comet ISON in 2013, Comet Lovejoy (C/2013 R1) still sweeps through early morning skies, captured in this starry scene on New Year's day. The frame stretches some 3.5 degrees across a background of faint stars in the constellation Hercules.

Zodiacal Light and Mars
10.03.2021

Just after sunset on March 7, a faint band of light still reaches above the western horizon in this serene, rural Illinois, night skyscape. Taken from an old farmstead, the luminous glow is zodiacal light, prominent in the west after sunset during planet Earth's northern hemisphere spring.

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.

Shell Galaxies in Pisces
26.08.2020

This intergalactic 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 right of center, the curious shell galaxy NGC 474 and its blue, spiral-armed neighbor NGC 470.

Orion over Green Bank
22.02.2022

What will the huge Green Bank Telescope discover tonight? Pictured, the Robert C. Byrd Green Bank Telescope (GBT) on the lower right is the largest fully-pointable single-dish radio telescope in the world. With...

From the Pleiades to the Eridanus Loop
22.03.2020

If you stare at an interesting patch of sky long enough, will it look different? In the case of Pleiades and Hyades star clusters -- and surrounding regions -- the answer is: yes, pretty different. Long...