Analemma over the Callanish Stones
17.09.2022

If you went outside at the same time every day and took a picture that included the Sun, how would the Sun's position change? A more visual answer to that question is an analemma, a composite image taken from the same spot at the same time over the course of a year.

Supernova Survivor
10.09.2005

Beginning with a full view of beautiful spiral galaxy M81, follow the insets (left, bottom, then right) to zoom in on a real survivor. Seen at the center of the final field on the right is a star identified as the survivor of a cosmic cataclysm -- the supernova explosion of its companion star.

Perijove 11: Passing Jupiter
7.09.2019

Here comes Jupiter! NASA's robotic spacecraft Juno is continuing on its 53-day, highly-elongated orbits around our Solar System's largest planet. The featured video is from perijove 11 in early 2018, the eleventh time Juno has passed near Jupiter since it arrived in mid-2016.

APOD: 2025 February 16 Б Perijove 11: Passing Jupiter
15.02.2025

Here comes Jupiter. NASA's robotic spacecraft Juno is continuing on its highly elongated orbits around our Solar System's largest planet. The featured video is from perijove 11 in early 2018, the eleventh time Juno passed near Jupiter since it arrived in mid-2016.

APOD: 2025 November 16 Б Crossing Saturns Ring Plane
15.11.2025

If this is Saturn, where are the rings? When Saturn's "appendages" disappeared in 1612, Galileo did not understand why. Later that century, it became understood that Saturn's unusual protrusions were rings and that when the Earth crosses the ring plane, the edge-on rings will appear to disappear.

Live: Watching for Venus to Cross the Sun
5.06.2012

Today Venus moves in front of the Sun. One way to follow this rare event is to actively reload the above live image of the Sun during the right time interval and look for an unusual circular dark dot. The smaller sprawling dark areas are sunspots. The circular dot is the planet Venus.

Blue Stragglers in NGC 6397
8.08.2003

In our neck of the Galaxy stars are too far apart to be in danger of colliding, but in the dense cores of globular star clusters star collisions may be relatively common. In fact...

Z Machine Sets Unexpected Earth Temperature Record
12.03.2006

Why is this plasma so hot? Physicists aren't sure. What is known for sure is that the Z Machine running at Sandia National Laboratories created a plasma that was unexpectedly hot. The plasma...

Launch of the Parker Solar Probe
14.08.2018

When is the best time to launch a probe to the Sun? The now historic answer -- which is not a joke because this really happened this past weekend -- was at night. Night, not only...

Simulation: Formation of the First Stars
29.06.2021

How did the first stars form? To help find out, the SPHINX computer simulation of star formation in the very early universe was created, some results of which are shown in the featured video. Time since the Big Bang is shown in millions of years on the upper left.