Hitomi Launches
18.02.2016

On February 17 at 5:45pm JST this H-IIA rocket blasted skyward from JAXA's Tanegashima Space Center located off the southern coast of Japan, planet Earth. Onboard was the ASTRO-H X-ray astronomy satellite, now in orbit.

IC 4406: A Seemingly Square Nebula
8.01.2017

How can a round star make a square nebula? This conundrum comes to light when studying planetary nebulae like IC 4406. Evidence indicates that IC 4406 is likely a hollow cylinder, with its square appearance the result of our vantage point in viewing the cylinder from the side.

Daphnis the Wavemaker
21.01.2017

Plunging close to the outer edges of Saturn's rings, on January 16 the Cassini spacecraft captured this closest yet view of Daphnis. About 8 kilometers across and orbiting within the bright ring system's Keeler gap, the small moon is making waves.

Mercury as Revealed by MESSENGER
23.07.2017

Mercury had never been seen like this before. In 2008, the robotic MESSENGER spacecraft buzzed past Mercury for the second time and imaged terrain mapped previously only by comparatively crude radar. The featured image was recorded as MESSENGER looked back 90 minutes after passing, from an altitude of about 27,000 kilometers.

AZURE Vapor Tracers over Norway
8.04.2019

What's happening in the sky? The atmosphere over northern Norway appeared quite strange for about 30 minutes last Friday when colorful clouds, dots, and plumes suddenly appeared. The colors were actually created by the NASA-funded Auroral Zone Upwelling Rocket Experiment (AZURE) which dispersed gas tracers to probe winds in Earth's upper atmosphere.

Stereo Helene
15.06.2019

Get out your red/blue glasses and float next to Helene, small, icy moon of Saturn. Appropriately named, Helene is one of four known Trojan moons, so called because it orbits at a Lagrange point. A Lagrange point is a gravitationally stable position near two massive bodies, in this case Saturn and larger moon Dione.

Io in True Color
11.12.2022

The strangest moon in the Solar System is bright yellow. The featured picture, an attempt to show how Io would appear in the "true colors" perceptible to the average human eye, was taken in 1999 July by the Galileo spacecraft that orbited Jupiter from 1995 to 2003.

APOD: 2024 October 27 Б LDN 43: The Cosmic Bat Nebula
27.10.2024

What is the most spook-tacular nebula in the galaxy? One contender is LDN 43, which bears an astonishing resemblance to a vast cosmic bat flying amongst the stars on a dark Halloween night. Located...

The Hubble Deep Field
9.07.2000

Galaxies like colorful pieces of candy fill the Hubble Deep Field - one of humanity's most distant optical views of the Universe. The dimmest, some as faint as 30th magnitude (about four billion times...

Behind CL1358+62: A New Farthest Object
31.07.1997

What if we could see back to the beginning of the universe? At one tenth the universe's present age, we might see galaxies forming. But what did galaxies look like when they were forming?