Swift RocketCam
24.12.2004

A forward-facing RocketCam (TM) mounted inside the payload fairing of a Delta II rocket captured these dramatic video frames on November 20th -- as the Swift satellite observatory journeyed to an orbit 600 kilometers above planet Earth. Some frames were interpolated to correct for transmission problems.

Earth size Kepler 186f
19.04.2014

Planet Kepler-186f is the first known Earth-size planet to lie within the habitable zone of a star beyond the Sun. Discovered using data from the prolific planet-hunting Kepler spacecraft, the distant world orbits...

NuSTAR XRay Telescope Launched
19.06.2012

What's left after a star explodes? To help find out, NASA launched the Nuclear Spectroscopic Telescope Array (NuSTAR) satellite into Earth orbit last week. NuSTAR's ability to focus hard X-rays emitted from...

APOD: 2024 December 22 Б The Local Fluff
22.12.2024

The stars are not alone. In the disk of our Milky Way Galaxy, about 10 percent of visible matter is in the form of gas called the interstellar medium (ISM). The ISM is not uniform and shows patchiness even near our Sun.

A Double Ringed Basin on Mercury
7.10.2009

What created the internal second ring of this double ringed basin on Mercury? No one is sure. The unusual feature spans 160 kilometers and was imaged during the robotic MESSENGER spacecraft's swing past our Solar System's innermost planet last week.

Cluster Crash Illuminates Dark Matter Conundrum
20.08.2007

Huge clusters of galaxies are surely colliding in Abell 520 but astrophysicists aren't sure why the dark matter is becoming separated from the normal matter. The dark matter in the above multi-wavelength image is shown in false blue, determined by carefully detailing how the cluster distorts light emitted by more distant galaxies.

SIRTF Streak
5.09.2003

Streaking skyward, a Boeing Delta 2-Heavy rocket carries NASA's Space InfraRed Telescope Facility (SIRTF) aloft during the early morning hours of August 25th. The dramatic scene was recorded in a time exposure from...

Zodiacal Light Panorama
5.04.2012

Sweeping from the eastern to western horizon, this 360 degree panorama follows the band of zodiacal light along the solar system's ecliptic plane. Dust scattering sunlight produces the faint zodiacal glow that spans...

Julius Caesar and Leap Days
29.02.2020

In 46 BC Julius Caesar reformed the calendar system. Based on advice by astronomer Sosigenes of Alexandria, the Julian calendar included one leap day every four years to account for the fact that an Earth year is slightly more than 365 days long.

Animation: Perseid Meteor Shower
8.08.2018

Where do Perseid meteors come from? Mostly small bits of stony grit, Perseid meteoroids were once expelled from Comet Swift-Tuttle and continue to follow this comet's orbit as they slowly disperse. The featured animation depicts the entire meteoroid stream as it orbits our Sun.