APOD: 2024 April 21 Б Perijove 16: Passing Jupiter
20.04.2024

Watch Juno zoom past Jupiter. NASA's robotic spacecraft Juno is continuing on its now month-long, highly-elongated orbits around our Solar System's largest planet. The featured video is from perijove 16, the sixteenth time that Juno passed near Jupiter since it arrived in mid-2016.

Anemic Spiral NGC 4921 from Hubble
14.05.2019

How far away is spiral galaxy NGC 4921? It's surpringly important to know. Although presently estimated to be about 300 million light years distant, a more precise determination could be coupled with its known recession speed to help humanity better calibrate the expansion rate of the entire visible universe.

Abell 370: Galaxy Cluster Gravitational Lens
21.09.2009

What is that strange arc? While imaging the cluster of galaxies Abell 370, astronomers had noted an unusual arc to the right of many cluster galaxies. Although curious, one initial response was to avoid commenting on the arc because nothing like it had ever been noted before.

A Total Lunar Eclipse Over Tajikistan
6.11.2022

If the full Moon suddenly faded, what would you see? The answer was recorded in a dramatic time lapse video taken during the total lunar eclipse in 2011 from Tajikistan. During a total lunar eclipse, the Earth moves between the Moon and the Sun, causing the moon to fade dramatically.

APOD: 2020 July 22 Б The Structured Tails of Comet NEOWISE
21.07.2020

What is creating the structure in Comet NEOWISE's tails? Of the two tails evident, the blue ion tail on the left points directly away from the Sun and is pushed out by the flowing and charged solar wind.

Hale-Bopp, Jupiter, and the Milky Way
23.07.1996

Shining brightly, the mighty Jupiter rules this gorgeous Kodacolor photo of the Milky Way near Sagittarius. Astronomer Bill Keel took the picture earlier this month (July 7) while standing near the summit of Hawaii's Mauna Kea contemplating the sky in the direction of the center of the Galaxy (right of picture center).

Tycho and Clavius
4.08.2021

South is up in this detailed telescopic view across the Moon's rugged southern highlands. Captured on July 20, the lunar landscape features the Moon's young and old, the large craters Tycho and Clavius.

Simulation: A Disk Galaxy Forms
17.07.2012

How do galaxies like our Milky Way form? Since our universe moves too slowly to watch, faster-moving computer simulations are created to help find out. Green depicts (mostly) hydrogen gas in the above movie, while time is shown in billions of years since the Big Bang on the lower right.

Neutrinos in the Sun
5.06.1998

Neutrinos, along with things like electrons and quarks, are fundamental pieces of matter according to physicists' Standard Model. But neutrinos are hard to detect. Readily produced in nuclear reactions and particle collisions, they can easily pass completely through planet Earth without once interacting with any other particle.

Abell 370: Galaxy Cluster Gravitational Lens
27.08.2016

What is that strange arc? While imaging the cluster of galaxies Abell 370, astronomers had noted an unusual arc to the right of many cluster galaxies. Although curious, one initial response was to avoid commenting on the arc because nothing like it had ever been noted before.