Astronomy Picture Of the Day (APOD)Great Conjunction over Sicilian Lighthouse
DonБt miss the coming great conjunction. In just under two weeks, the two largest planets in our Solar System will angularly pass so close together in Earth's sky that the Moon would easily be able to cover them both simultaneously. This pending planetary passage -- on December 21 -- will be the closest since 1623.
Mammatus Clouds over Mount Rushmore
What's that below those strange clouds? Presidents. If you look closely, you may recognize the heads of four former US Presidents carved into famous Mount Rushmore in South Dakota, USA. More obvious in the featured image are the unusual mammatus clouds that passed briefly overhead.
M16: Pillars of Star Creation
These dark pillars may look destructive, but they are creating stars. This pillar-capturing image of the inside of the Eagle Nebula, taken with the Hubble Space Telescope in 1995, shows evaporating gaseous globules (EGGs) emerging from pillars of molecular hydrogen gas and dust.
Mons Rumker in the Ocean of Storms
Mons Rumker, a 70 kilometer wide complex of volcanic domes, rises some 1100 meters above the vast, smooth lunar mare known as Oceanus Procellarum, the Ocean of Storms. Daylight came to the area late last month.
Curly Spiral Galaxy M63
A bright spiral galaxy of the northern sky, Messier 63 is nearby, about 30 million light-years distant toward the loyal constellation Canes Venatici. Also cataloged as NGC 5055, the majestic island universe is nearly 100,000 light-years across, about the size of our own Milky Way.
The Antennae Galaxies in Collision
Sixty million light-years away toward the southerly constellation Corvus, these two large galaxies are colliding. The cosmic train wreck captured in stunning detail in this Hubble Space Telescope snapshot takes hundreds of millions of years to play out. Cataloged as NGC 4038 and NGC 4039, the galaxies' individual stars don't often collide though.
Eye of Moon
Who's watching who? The featured image of the Moon through a gap in a wall of rock may appear like a giant eye looking back at you. Although, in late October, it took only a single exposure to capture this visual double, it also took a lot of planning.
NGC 346: Star Forming Cluster in the SMC
Are stars still forming in the Milky Way's satellite galaxies? Found among the Small Magellanic Cloud's (SMC's) clusters and nebulas, NGC 346 is a star forming region about 200 light-years across, pictured here in the center of a Hubble Space Telescope image.
Cygnus Without Stars
The sky is filled with faintly glowing gas, though it can take a sensitive camera and telescope to see it. For example, this twelve-degree-wide view of the northern part of the constellation Cygnus reveals a complex array of cosmic clouds of gas along the plane of our Milky Way galaxy.
Verona Rupes: Tallest Known Cliff in the Solar System
Could you survive a jump off the tallest cliff in the Solar System? Quite possibly. Verona Rupes on Uranus' moon Miranda is estimated to be 20 kilometers deep -- ten times the depth of the Earth's Grand Canyon.