Young Star Cluster Trumpler 14 from Hubble
14.05.2019

Why does star cluster Trumpler 14 have so many bright stars? Because it is so young. Many cluster stars have formed only in the past 5 million years and are so hot they emit detectable X-rays.

Ship Tracks over the Pacific Ocean
8.06.2022

What are those unusual streaks? Some images of planet Earth show clear bright streaks that follow the paths of ships. Known as ship tracks, these low and narrow bands are caused by the ship's engine exhaust.

APOD: 2023 October 9 Б A Distorted Sunrise Eclipse
9.10.2023

Yes, but have you ever seen a sunrise like this? Here, after initial cloudiness, the Sun appeared to rise in two pieces and during a partial eclipse in 2019, causing the photographer to describe it as the most stunning sunrise of his life.

Perigee Moon, Apogee Moon
22.12.1999

Tonight, those blessed with clear skies can enjoy a glorious full moon, the last full moon of the "Y1.9K"s. In fact, tonight's moon will be a full-perigee-solstice moon, reaching its full phase and perigee (the closest point in its orbit) on the solstice, the first day of northern hemisphere winter.

Galaxy Zoo Catalogs the Universe
26.10.2009

You, too, can Zoo. The Galaxy Zoo project has been enabling citizen scientists -- inquisitive people like yourself armed with only a web browser-- to sort through the universe. Specifically, after a brief training session...

The Opposing Tails of Comet Garradd
28.02.2012

Why does Comet Garradd have two tails? Visible on the left, Comet Garradd's dust tail is composed of ice and dust bits that trial the comet in its orbit around the Sun. Visible...

Orbits of Potentially Hazardous Asteroids
12.08.2013

Are asteroids dangerous? Some are, but the likelihood of a dangerous asteroid striking the Earth during any given year is low. Because some past mass extinction events have been linked to asteroid impacts, however, humanity has made it a priority to find and catalog those asteroids that may one day affect life on Earth.

In the Shadow of Saturn
13.11.2013

In the shadow of Saturn, unexpected wonders appear. The robotic Cassini spacecraft now orbiting Saturn drifted in giant planet's shadow earlier this year and looked back toward the eclipsed Sun. Cassini saw a unique and celebrated view.

An Active Night over the Magellan Telescopes
21.02.2017

The night sky is always changing. Featured here are changes that occurred over a six hour period in late 2014 June behind the dual 6.5-meter Magellan Telescopes at Las Campanas Observatory in Chile.

Hayabusa2 Approaches Asteroid Ryugu
25.06.2018

It looks like a big space diamond -- but with craters. It's 162173 Ryugu (Dragon's Castle), and Japan's robotic Hayabusa2 mission is now arriving at this near-Earth asteroid. Ambitious Hayabusa2 is carrying...