Sunday, December 16, 2018

Today Comet Wirtanen Passes near the Earth

Today Comet Wirtanen passes by the Earth. The kilometer-sized dirty snowball orbits the Sun every 5.4 years, ranging as far out as Jupiter and as close in as the Earth. Today Comet 46P/Wirtanen passes within only 31 lunar distances to the Earth, the closest approach in 70 years. If you know where to look (Taurus), you can see the cometthrough binoculars as an unusual blue smudgePictured a week ago, Comet Wirtanen was photographed in the sky beyond an old abandoned church inSkagenDenmark. The image composite also captures the astrophotographer. After today, the comet will begin to fade as it recedes from the Earth and the Sun.

Image Credit & Copyright: Ruslan Merzlyakov (RMS Photography)

Friday, December 14, 2018

3D Bennu

Put on your red/blue glasses and float next to asteroid 101955 Bennu. Shaped like a spinning top toy with boulders littering its rough surface, the tiny Solar System world is about 1 Empire State Building (less than 500 meters) across. Frames used to construct this 3D anaglyph were taken by PolyCam on board the OSIRIS_REx spacecraft on December 3 from a distance of about 80 kilometers. Now settling in to explore Bennu from orbit, the OSIRIS-REx mission is expected to deliver samples of the asteroid to planet Earth in 2023. Samples of dust from another asteroid will streak through Earth's atmosphere much sooner though, when the Geminid meteor shower peaks in predawn skies on December 14. The parent body for the annual Geminids is asteroid 3200 Phaethon.
For image credit and copyright guidance, please visit the image website


Monday, December 10, 2018

Sound and Light Captured by Mars InSight

Your arm on Mars has unusual powers. For one thing it is nearly 2 meters long, has a scoop and grapple built into itshand, and has a camera built into itsforearm. For another, it will soon deploy your ear -- a sensitive seismometer that will listen for distant rumblings -- onto the surface of Mars. Your SEISmomet-ear is the orange box in the foreground, while the gray dome behind it will be its protective cover. Your arm is attached to the InSight robotic lander that touched down on Mars two weeks ago. Somewhat unexpectedly, your ear hasalready heard something -- slight vibrations caused by the Martian windflowing over the solar panels. Light from the Sun is being collected by the solar panels, part of one being visible on the far right. Actually, at the present time, you have two arms operating on Mars, but they are separated by about 600 kilometers. That's because your other active arm is connected to the Curiosity rover exploring a distant crater. Taken a week ago, rusty soil and rocks are visible in the featured image beyond Insight, as well as the orange sky of Mars.

Image Copyright: Image Credit:NASA/JPL-Caltech

Curiosity Mars Rover

Sunday, December 9, 2018

Highlights of the North Winter Sky

What can you see in the night sky this season? The featured graphic gives a few highlights for Earth's northern hemisphere. Viewed as a clock face centered at the bottom, early (northern) winter sky events fan out toward the left, while late winter events are projected toward the right. Objects relatively close to Earth are illustrated, in general, as nearer to the cartoon figure with the telescope at the bottom center -- although almost everything pictured can be seen without a telescope. As happens during any season,constellations appear the same year to year, and, as usual, the Geminids meteor shower will peak in mid-December. Also as usual, the International Space Station(ISS) can be seen, at times, as a bright spot drifting across the sky after sunset. Less usual, the Moon is expected topass nearly in front of several planets in early January. A treat this winter isComet 46P/Wirtanen, already bright, will pass only 36 lunar distances from the Earth in mid-December, potentially making it easily visible to the unaided eye.

Image Credit & Copyright:

The Fairy of Eagle Nebula

The dust sculptures of the Eagle Nebula are evaporating. As powerful starlight whittles away these cool cosmic mountains, the statuesque pillars that remain might be imagined as mythical beasts. Featured here is one of several striking dust pillars of the Eagle Nebulathat might be described as a gigantic alien fairy. This fairy, however, is tenlight years tall and spews radiation much hotter than common fire. Thegreater Eagle Nebula, M16, is actually a giant evaporating shell of gas and dustinside of which is a growing cavity filled with a spectacular stellar nursery currently forming an open cluster of stars. This great pillar, which is about 7,000 light years away, will likely evaporate away in about 100,000 years. The featured image in scientifically re-assigned colors was released in 2005 as part of the fifteenth anniversary celebration of the launch of the Hubble Space Telescope.

Image Copyright: Image Credit: NASA,ESAThe Hubble Heritage Team, (STScI/AURA)

Hubble Space Telescope

Saturday, December 1, 2018

IC 1871: Inside the Soul Nebula

This cosmic close-up looks deep inside the Soul Nebula. The dark and broodingdust clouds on the left, outlined by bright ridges of glowing gas, are cataloged as IC 1871. About 25 light-years across, the telescopic field of view spans only a small part of the much larger Heart and Soul nebulae. At an estimated distance of 6,500 light-years the star-forming complex lies within thePerseus spiral arm of our Milky WayGalaxy, seen in planet Earth's skies toward the constellation Cassiopeia. An example of triggered star formation, the dense star-forming clouds of IC 1871 are themselves sculpted by the intense winds and radiation of the region's massive young stars. The featured image appears mostly red due to the emission of a specific color of light emitted by excited hydrogen gas.

Image Credit & Copyright: Mark Hanson

Hubble Explores the Coma Cluster's More Than 1,000 Galaxies

This Hubble Space Telescope mosaic is of a portion of the immense Coma cluster of over 1,000 galaxies, located 300 million light-years from Earth. Hubble's incredible sharpness was used to conduct a comprehensive census of the cluster's most diminutive members: a whopping 22,426 globular star clusters. Among the earliest homesteaders of the universe, globular star clusters are snow-globe-shaped islands of several hundred thousand ancient stars. The survey found the globular clusters scattered in the space between the galaxies. They have been orphaned from their home galaxies through galaxy tidal interactions within the bustling cluster. Astronomers will use the globular cluster field for mapping the distribution of matter and dark matter in the Coma galaxy cluster.

The study, published in the November 9, 2018, issue of The Astrophysical Journal, will allow for astronomers to use the globular cluster field to map the distribution of matter and dark matter in the Coma galaxy cluster.

Image Credit: NASA, ESA, J. Mack (STScI) and J. Madrid (Australian Telescope National Facility)

Hubble Space Telescope