Dark Matter in a Simulated Universe
25.10.2020

Is our universe haunted? It might look that way on this dark matter map. The gravity of unseen dark matter is the leading explanation for why galaxies rotate so fast, why galaxies orbit clusters...

Starburst Galaxy M94 from Hubble
31.07.2022

Why does this galaxy have a ring of bright blue stars? Beautiful island universe Messier 94 lies a mere 15 million light-years distant in the northern constellation of the Hunting Dogs (Canes Venatici).

APOD: 2024 May 15 Б AR 3664 at the Suns Edge
15.05.2024

What did the monster active region that created the recent auroras look like when at the Sun's edge? There, AR 3664 better showed its 3D structure. Pictured, a large multi-pronged solar prominence...

Ancient Craters of Southern Rhea
13.05.2008

Saturn's ragged moon Rhea has one of the oldest surfaces known. Estimated as changing little in the past billion years, Rhea shows craters so old they no longer appear round their edges have become compromised by more recent cratering.

The Long Jet of the Lighthouse Nebula
21.02.2014

The Lighthouse nebula was formed by the wind of a pulsar, a rapidly rotating, magnetized neutron star, as it speeds through the interstellar medium at over 1,000 kilometers per second. Some...

A Face in the Clouds of Jupiter from Juno
8.06.2021

What do you see in the clouds of Jupiter? On the largest scale, circling the planet, Jupiter has alternating light zones and reddish-brown belts. Rising zone gas, mostly hydrogen and helium, usually swirls around regions of high pressure. Conversely, falling belt gas usually whirls around regions of low pressure, like cyclones and hurricanes on Earth.

Fermi Epicyles: The Vela Pulsar s Path
4.05.2012

Exploring the cosmos at extreme energies, the Fermi Gamma-ray Space Telescope orbits planet Earth every 95 minutes. By design, it rocks to the north and then to the south on alternate orbits in order to survey the sky with its Large Area Telescope (LAT).

A Milky Way Shadow at Loch Ard Gorge
23.08.2010

Have you ever seen the Milky Way's glow create shadows? To do so, conditions need to be just right. First and foremost, the sky must be relatively clear of clouds so that the long band of the Milky Way's central disk can be seen.

Elements in the Aftermath
26.10.2001

Massive stars spend their brief lives furiously burning nuclear fuel. Through fusion at extreme temperatures and densities surrounding the stellar core, nuclei of light elements like Hydrogen and Helium are combined to heavier elements like Carbon, Oxygen, etc. in a progression which ends with Iron.

M87: Elliptical Galaxy with Jet
20.05.2010

In spiral galaxies, majestic winding arms of young stars, gas, and dust rotate in a flat disk around a bulging galactic nucleus. But elliptical galaxies seem to be simpler. Lacking gas and dust to form new stars, their randomly swarming older stars, give them an ellipsoidal (egg-like) shape. Still, elliptical galaxies can be very large.