A Cosmic Snowball
30.05.1997

Like cosmic snowballs, fluffy comet-like objects the size of houses and composed mostly of water-ice, may be pummeling planet Earth 5 to 30 times a minute. This controversial theory was originally proposed in 1986 by Dr. Louis Frank (U. Iowa) based on data from NASA's Dynamics Explorer 1.

Illustris Simulation of the Universe
22.02.2020

How did we get here? Click play, sit back, and watch. A computer simulation of the evolution of the universe provides insight into how galaxies formed and perspectives into humanity's place in the universe.

APOD: 2023 December 31 Б Illustris: A Simulation of the Universe
30.12.2023

How did we get here? Click play, sit back, and watch. A computer simulation of the evolution of the universe provides insight into how galaxies formed and perspectives into humanity's place in the universe.

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.

The Broad Tail of PanSTARRS
30.03.2013

For northern hemisphere skygazers, fading Comet PanSTARRS (C/2011 L4) still hangs above the western horzion, after sunset but before moonrise in the coming days. Its perspective from planet Earth continues to reveal the comet's broad dust tail.

M81 and Arp s Loop
8.12.2010

One of the brightest galaxies in planet Earth's sky and similar in size to the Milky Way, big, beautiful spiral M81 lies 11.8 million light-years away in the northern constellation Ursa Major. This...

Illustris Simulation of the Universe
12.05.2014

How did we get here? Click play, sit back, and watch. A new computer simulation of the evolution of the universe -- the largest and most sophisticated yet produced -- provides new insight into how galaxies formed and new perspectives into humanity's place in the universe.

Cancri 55 e: Climate Patterns on a Lava World
4.04.2016

Why might you want to visit super-earth Cancri 55 e? Its extremely hot climate would be a deterrent, as mornings on this world might bring fresh lava flows. Discovered in 2004, the planet Cancri 55 e has twice the diameter of our Earth and about 10 times Earth's mass.

ROSAT Explores The X-Ray Sky
8.10.1996

Launched in 1990, the orbiting ROSAT observatory explored the Universe by viewing the entire sky in x-rays - photons with about 1,000 times more energy than visible light. This ROSAT survey produced the sharpest, most sensitive image of the x-ray sky to date.

Fermi s Gamma Ray Sky
20.03.2009

Scanning the entire sky in gamma-rays, photons with over 50 million times the energy of visible light, the Fermi mission's Large Area Telescope (LAT) explores the high-energy universe. This all-sky map constructed from...