APOD: 2025 June 15 Б Two Worlds One Sun
15.06.2025

How different does sunset appear from Mars than from Earth? For comparison, two images of our common star were taken at sunset, one from Earth and one from Mars. These images were scaled to have the same angular width and are featured here side-by-side.

Hyakutake, Big Dipper, and Observatory Dome
1.04.1996

In one of the more spectacular pictures yet taken, Comet Hyakutake is shown here on March 26 high in the dark Missouri sky. In the foreground is Elmcrest Observatory complete with a dim red light glowing inside the dome.

The Vela Pulsar s Dynamic Jet
3.07.2003

The Vela pulsar is a neutron star born over 10,000 years ago in a massive supernova explosion. Above, false-color x-ray images from the Chandra Observatory reveal details of this remnant pulsar's x-ray bright nebula along with emission from a spectacular jet of high-energy particles.

Albert Einstein s Miraculous Year
22.04.2005

In 1905 Albert Einstein had a miraculous year. One hundred years ago, he wrote four papers which revolutionized our understanding of the Universe. The papers outlined; the idea that light could behave...

SOFIA s Window Seat
25.02.2006

Earlier this month, a 2.5-meter diameter infrared telescope was permanently assigned a window seat, looking through this opening in the fuselage of a historic Boeing 747 aircraft. The telescope mirror, about the size of the Hubble Space Telescope mirror, is protected by a red covering.

Rumors of a Strange Universe
24.12.2006

Eight years ago results were first presented indicating that most of the energy in our universe is not in stars or galaxies but is tied to space itself. In the language of cosmologists, a large cosmological constant is directly implied by new distant supernovae observations.

NGC 2261: Hubble s Variable Nebula
8.11.2017

What causes Hubble's Variable Nebula to vary? The unusual nebula featured here changes its appearance noticeably in just a few weeks. Discovered over 200 years ago and subsequently cataloged as NGC 2661, the remarkable nebula is named for Edwin Hubble, who studied it early last century.

The Spider Nebula in Infrared
4.09.2019

Will the spider ever catch the fly? Not if both are large emission nebulas toward the constellation of the Charioteer (Auriga). The spider-shaped gas cloud on the left is actually an emission nebula labelled...

Mars, Pleiades, and Andromeda over Stone Lions
13.10.2020

Three very different -- and very famous -- objects were all captured in a single frame last month. On the upper left is the bright blue Pleiades, perhaps the most famous cluster of stars on the night sky. The Pleiades (M45) is about 450 light years away and easily found a few degrees from Orion.

APOD: 2025 May 7 Б Galaxy Wars: M81 versus M82
7.05.2025

In the upper left corner, surrounded by blue arms and dotted with red nebulas, is spiral galaxy M81. In the lower right corner, marked by a light central line and surrounded by red glowing gas, is irregular galaxy M82.