NGC 6946 is a medium-sized, face-on spiral galaxy about 22 million light years away from Earth. In the past century, eight supernovas have been observed to explode in the arms of this galaxy. Chandra observations (purple) have, in fact, revealed three of the oldest supernovas ever detected in X-rays, giving more credence to its nickname of the “Fireworks Galaxy.” This composite image also includes optical data from the Gemini Observatory in red, yellow, and cyan.
Image: X-ray: NASA/CXC/MSSL/R.Soria et al, Optical: AURA/Gemini OBs [high-resolution]
An annular eclipse flares briefly above Kenya’s Lake Turkana last Sunday (Nov. 13, 2013). The solar eclipse was viewable from almost all of Africa, but only a narrow swath of the continent saw a total eclipse of the sun during the event.
Lake Turkana was one of those places that briefly saw the total eclipse. It also afforded views of an annular eclipse, which occurs when the moon almost but not quite covers the solar disc. That allows the sun’s corona to brightly rim the edges of the moon, as seen in this picture.
A quintet of Saturn’s moons dance elegantly above the planet’s famed rings in this photo taken by the Cassini spacecraft and released November 4.In orbit around the ringed planet since 2004, Cassini has offered unparalleled views of Saturn’s rings and moons, including this picture shot from slightly above the plane of the rings.
On the right, the closest moon is Rhea, which is Saturn’s second-largest satellite, and in the center is Enceladus, shining brightly with frost vented from its south pole geysers.
Jellyfish Nebula, the gas-filled remains of a distant stellar explosion, seems to swim away from remnants of its former home in a photo uploaded to Your Shot on November 2. Some 5,200 light-years away, the nebula is joined on its left by an “emission nebula,” a cloud of electrically charged gas thrown off an exploded star.
Hubble sees asteroid spouting six comet-like tails
(Phys.org) — Astronomers using NASA’s Hubble Space Telescope have identified what they can only describe as a never-before-seen “weird and freakish object” in the asteroid belt that looks like a rotating lawn sprinkler.
Normal asteroids should appear simply as tiny points of light. But this asteroid, designated P/2013 P5, has six comet-like tails of dust radiating from it like spokes on a wheel.Because nothing like this has ever been seen before, astronomers are scratching their heads to find an adequate explanation for its out-of-this-world appearance… (read more)
This chat starts at 4 p.m. EST., Thursday, Nov. 7th. Please check just before then for the video window to appear.
Roughly 85% of the matter in the universe is dark matter, the mysterious stuff whose gravity holds the galaxies together but that has not revealed itself in any other way. Although many physicists think that dark matter consists of beefy “weakly interacting massive particles,” or WIMPs, it’s also possible that it’s made of incredibly light particles known as axions that physicists dreamed up for another reason entirely. Over the next 3 years, the Axion Dark Matter Experiment, or ADMX, aims to detect those odd particles and either prove conclusively that axions are dark matter or that they can’t be.
Join Gianpaolo Carosi, the spokesperson for the ADMX team, and Frank Wilczek, a theorist who helped develop the concept of the axion, on Thursday, 7 November, on the linked page, for a live chat about what axions are and how physicists hope to detect them. Be sure to leave your questions for our guests in the comment box below…
Now that November has arrived it’s time to get ready for Comet C/2012 S1 (ISON). On November 28 (yes, Thanksgiving Day) at 1:45 pm ET, Comet ISON will fly only 730,000 miles above the surface of the Sun. Even though it is moving as fast as 375 km/s (840,000 mph), the Sun will heat Comet ISON, causing it to sublimate and leave a lot of water and grit behind. Comet ISON is about 2 km across, much bigger than Comet Lovejoy in December 2011, and it will leave a lot of itself behind.
Once the stuff sublimates we will watch for it to light up the corona in the AIA bandpasses. We saw Comet Lovejoy in 7 of the 10 bandpasses in December 2011. This time we will point SDO toward three different places where the comet is predicted to be. One will be centered about the time of perihelion for a half hour on each side of perihelion…
Kepler Telescope Finds Plethora of Earth-Size Planets
NASA’s premier planet-hunting scope turns up 647 possible Earth-size worlds in the Milky Way
By Clara Moskowitz
A little more than two decades ago, no planets had ever been detected outside the solar system. Now, more than 1,000 extrasolar planets have been confirmed, and on Monday the team behind the Kepler Space Telescope announced a haul of 833 more candidate planets to consider adding to the tally.
This embarrassment of riches is far beyond what scientists dared to hope for before NASA launched the Kepler mission in 2009. The telescope, in permanent orbit around the sun, identifies planets by watching them “transit,” or pass in front of, their stars, briefly dimming the stars’ light. “When I first started working with Kepler right before launch, I thought there would be maybe a thousand planets that Kepler would find,” Jason Rowe, an astronomer at the Search for Extraterrestrial Intelligence Institute in Mountain View, Calif., said during a press conference Monday at the Kepler Science Conference in Moffett Field, Calif.
In actuality, Kepler has uncovered more than 3,500 candidate exoplanets in its first three years, including large and small planets, rocky and gaseous worlds, and a total of 647 possible planets that appear to be Earth-sized…
The spectacular swirling arms and central bar of the Sculptor galaxy are revealed in this new view from NASA’s Spitzer Space Telescope. This image is an infrared composite combining data from two of Spitzer’s detectors taken during its early cold, or cryogenic, mission.
Also known as NGC 253, the Sculptor galaxy is part of a cluster of galaxies visible to observers in the Southern hemisphere. It is known as a starburst galaxy for the extraordinarily strong star formation in its nucleus. This activity warms the surrounding dust clouds, causing the brilliant yellow-red glow in the center of this infrared image.
Figure 1 is split into two constituent parts on the right. On the top is a blue glow primarily from the light of stars as seen at the shorter wavelengths of infrared light. In this view, the disk, spiral arms and central bar are easy to see. The lower right image shows the glow of dust at longer infrared wavelengths in green and red. Regions of star formation glow especially bright at the longest wavelengths (red)…
Jets generated by supermassive black holes at the centers of galaxies can transport huge amounts of energy across great distances. 3C353 is a wide, double-lobed source where the galaxy is the tiny point in the center and giant plumes of radiation can be seen in X-rays from Chandra (purple) and radio data from the Very Large Array (orange).
Image: X-ray: NASA/CXC/Tokyo Institute of Technology/J.Kataoka et al, Radio: NRAO/VLA [high-resolution]
A witch appears to be screaming out into space in this new image from NASA’s Wide-Field Infrared Survey Explorer, or WISE. The infrared portrait shows the Witch Head nebula, named after its resemblance to the profile of a wicked witch. Astronomers say the billowy clouds of the nebula, where baby stars are brewing, are being lit up by massive stars. Dust in the cloud is being hit with starlight, causing it to glow with infrared light, which was picked up by WISE’s detectors.
The Witch Head nebula is estimated to be hundreds of light-years away in the Orion constellation, just off the famous hunter’s knee. WISE was recently “awakened” to hunt for asteroids in a program called NEOWISE. The reactivation came after the spacecraft was put into hibernation in 2011, when it completed two full scans of the sky, as planned.
This trio of ghostly images from NASA’s Spitzer Space Telescope shows the disembodied remains of dying stars called planetary nebulas. Planetary nebulas are a late stage in a sun-like star’s life, when its outer layers have sloughed off and are lit up by ultraviolet light from the central star. They come in a variety of shapes, as indicated by these three spooky structures. In all of the images, infrared light at wavelengths of 3.6 microns is rendered in blue, 4.5 microns in green, and 8.0 microns in red.
Exposed Cranium Nebula (left) - The brain-like orb called PMR 1 has been nicknamed the “Exposed Cranium” nebula by Spitzer scientists. This planetary nebula, located roughly 5,000 light-years away in the Vela constellation, is host to a hot, massive dying star that is rapidly disintegrating, losing its mass. The nebula’s insides, which appear mushy and red in this view, are made up primarily of ionized gas, while the outer green shell is cooler, consisting of glowing hydrogen molecules.
Ghost of Jupiter Nebula (middle) - The Ghost of Jupiter, also known as NGC 3242, is located roughly 1,400 light-years away in the constellation Hydra. Spitzer’s infrared view shows off the cooler outer halo of the dying star, colored here in red. Also evident are concentric rings around the object, the result of material being periodically tossed out in the star’s final death throes.
Little Dumbbell Nebula (right)This planetary nebula, known as NGC 650 or the Little Dumbbell, is about 2,500 light-years from Earth in the Perseus constellation. Unlike the other spherical nebulas, it has a bipolar or butterfly shape due to a “waist,” or disk, of thick material, running from lower left to upper right. Fast winds blow material away from the star, above and below this dusty disk. The ghoulish green and red clouds are from glowing hydrogen molecules, with the green area being hotter than the red.
Solar flares release strong radiation outbursts, ones sometimes strong enough to interfere with radio signals on Earth. This October 23 outburst clocked in near the top of the “medium” class of such flares, making it an M9.4-class solar flare.
Such flares have become more common with the sun now near the peak of its regular sunspot activity cycle.
SDO watches for such outbursts in the infrared spectrum, as seen here, to see details of flares washed out or unseen in visible-light images.
A canyon of fire remains behind as an arc of solar material blasts off from the sun’s surface and punches through the solar atmosphere.The 200,000-mi-long (321,000-km-long) string of charged particles was fired from the sun by a clash of powerful magnetic field loops. As the loops pulled apart, they lofted the filament through the solar atmosphere, where temperatures reach 1.8 million°F (1 million°C). (Learn about the sun’s magnetic field.)The eruption’s buildup took place over two days from October 29 to October 30, captured by NASA’s Solar Dynamics Laboratory.