APOD: 2020 August 14 Б NGC 5189: An Unusually Complex Planetary Nebula
14.08.2020

Why is this nebula so complex? When a star like our Sun is dying, it will cast off its outer layers, usually into a simple overall shape. Sometimes this shape is a sphere, sometimes a double lobe, and sometimes a ring or a helix.

A Year of Resolving Cosmology
31.12.2003

This year, humanity learned that the universe is 13.7 billion years old. Before this year, the universe's age was thought to be about 13 billion years, but really only constrained to be between about 12 billion and 15 billion years old.

CMBR Dipole: Speeding Through the Universe
8.05.2005

Our Earth is not at rest. The Earth moves around the Sun. The Sun orbits the center of the Milky Way Galaxy. The Milky Way Galaxy orbits in the Local Group of Galaxies. The Local Group falls toward the Virgo Cluster of Galaxies.

Discovery s Cloud
8.04.2010

The space shuttle orbiter Discovery is now docked with the International Space Station, some 350 kilometers above planet Earth. Last Monday, its launch to orbit was a beautiful one as it rose into clear, predawn skies at 6:21am EDT from Kennedy Space Center's pad 39A.

X Ray Superbubbles in Galaxy NGC 3079
5.03.2019

What created these huge galactic superbubbles? Two of these unusual bubbles, each spanning thousands of light-years, were recently discovered near the center of spiral galaxy NGC 3079. The superbubbles, shown in purple on the image right, are so hot they emit X-rays detected by NASA's Earth-orbiting Chandra X-Ray Observatory.

Cold Comet Halley
3.10.2003

While this may not be the most esthetic image of Comet Halley that you have ever seen, it is likely the most unique. The tiny cluster of pixels circled is the famous comet along...

COBE Dipole: Speeding Through the Universe
8.03.1997

Our Earth is not at rest. The Earth moves around the Sun. The Sun orbits the center of the Milky Way Galaxy. The Milky Way Galaxy orbits in the Local Group. The Local Group falls toward the Virgo Cluster of Galaxies.

APOD: 2023 October 17 Б PDS 70: Disk, Planets, and Moons
17.10.2023

It's not the big ring that's attracting the most attention. Although the big planet-forming ring around the star PDS 70 is clearly imaged and itself quite interesting. It's also not the planet on the right, just inside the big disk, thatБs being talked about the most.

Symbiotic Star Bubbles
31.08.1999

The two stars at the center of this nebula are very different. One is a white dwarf star with a mass similar to our Sun but with a radius as small as our Earth.

Hubble Floats Free
6.03.1997

Why put observatories in space? Most telescopes are on the ground. On the ground, you can deploy a heavier telescope and upgrade it more easily. The trouble is that Earth-bound telescopes must look through the Earth's atmosphere.