The constellation Coma Berenices contains a plethora of galaxies. Some of the most prominent ones appear in this image. Unbarred spiral galaxy M99 (center of image) lies 50 million light-years away. Just above it is edge-on spiral NGC 4302, at a distance of about 54 million light-years with its close neighbor NGC 4298 (just below) at about 53 million light-years. Spiral galaxy M98 (lower right) lies at a distance of 44.4 million light-years. M100 (top right) lies 55 million light-years distant. Edge-on spiral NGC 4216 (lower left) stands just inside the constellation Virgo and is part of the huge Virgo cluster. To the upper right are Virgo cluster members NGC 4222 and NGC 4206.
Sounding Rocket Launches Into Aurora Over Venetie, Alaska
On March 3, 2014, at 6:09 a.m. EST, a NASA-funded sounding rocket launched straight into an aurora over Venetie, Alaska. The Ground-to-Rocket Electrodynamics – Electron Correlative Experiment (GREECE) sounding rocket mission, which launched from Poker Flat Research Range in Poker Flat, Alaska, will study classic curls in the aurora in the night sky.
The GREECE mission seeks to understand what combination of events sets up these auroral curls as they're called, in the charged, heated gas – or plasma – where aurorae form. This is a piece of information, which in turn, helps paint a picture of the sun-Earth connection and how energy and particles from the sun interact with Earth's own magnetic system, the magnetosphere.
Phoebe's true nature is revealed in startling clarity in this mosaic of two images taken during Cassini's flyby on June 11, 2004. This image of Saturn’s moon shows evidence for the emerging view that Phoebe may be an ice-rich body coated with a thin layer of dark material. Small bright craters in the image are probably fairly young features. This phenomenon has been observed on other icy satellites, such as Jupiter’s Ganymede.
When impactors slammed into the surface of Phoebe, the collisions excavated fresh, bright material -- probably ice -- underlying the surface layer. Further evidence for this can be seen on some crater walls where the darker material appears to have slid downwards, exposing more light-colored material. Some areas of the image that are particularly bright -- especially near lower right -- are over-exposed.
ESO’s Very Large Telescope spots largest yellow hypergiant star
This star measures more than 1,300 times the diameter of the Sun and is part of a double star system, with the second component so close that it is in contact with the main star.
HR 5171, the brightest star just below the center of this wide-field image, is a yellow hypergiant, a very rare type of stars with only a dozen known in our galaxy. Its size is over 1,300 times that of the Sun — one of the 10 largest stars found so far. Observations with ESO’s Very Large Telescope Interferometer have shown that it is actually a double star, with the companion in contact with the main star. ESO/Digitized Sky Survey 2
The European Southern Observatory’s (ESO) Very Large Telescope Interferometer (VLTI) has revealed the largest yellow star — and one of the 10 largest stars found so far. This hypergiant measures more than 1,300 times the diameter of the Sun and is part of a double star system, with the second component so close that it is in contact with the main star. Observations spanning over 60 years, some from amateur astronomers, also indicate that this rare and remarkable object is changing rapidly and has been caught during a brief phase of its life.
Using ESO’s VLTI, Olivier Chesneau from the Observatory de la Côte d’Azur in Nice, France, and an international team of collaborators have found that the yellow hypergiant star HR 5171 A is absolutely huge — much bigger than was expected. This makes it the largest yellow star known — 50 percent larger than the famous red supergiant Betelgeuse — and about 1 million times brighter than the Sun.
“The new observations also showed that this star has a very close binary partner, which was a real surprise,” said Chesneau. “The two stars are so close that they touch, and the whole system resembles a gigantic peanut.”
The astronomers made use of a technique called interferometry to combine the light collected from multiple individual telescopes, effectively creating a giant telescope up to 140 meters in size. The new results prompted the team to thoroughly investigate older observations of the star spanning more than 60 years to see how it had behaved in the past.
Yellow hypergiants are rare, with only a dozen or so known in our galaxy — the best-known example being Rho Cassiopeiae. They are among the biggest and brightest stars known and are at a stage of their lives when they are unstable and changing rapidly. Due to this instability, yellow hypergiants also expel material outward, forming a large extended atmosphere around the star.
Despite its great distance of nearly 12,000 light-years from Earth, the object can just about be seen with the naked eye by the keen-sighted. HR 5171 A has been found to be getting bigger over the past 40 years, cooling as it grows, and its evolution has now been caught in action. Only a few stars are caught in this brief phase where they undergo a dramatic change in temperature as they rapidly evolve.
By analyzing data on the star’s varying brightness using observations from other observatories, the astronomers confirmed the object to be an eclipsing binary system where the smaller component passes in front and behind the larger one as it orbits. In this case, the companion star orbits HR 5171 A every 1,300 days. The smaller companion is only slightly hotter than HR 5171 A’s surface temperature of 9000° Fahrenheit (5000° Celsius.)
“The companion we have found is very significant as it can have an influence on the fate of HR 5171 A, for example, stripping off its outer layers and modifying its evolution, Chesneau said.”
This new discovery highlights the importance of studying these huge and short-lived yellow hypergiants, and it could provide a means of understanding the evolutionary processes of massive stars in general.
Space Communications Antenna Supported Early NASA Missions
This 26 meter (85 foot) antenna operated in Woomera (Island Lagoon), Australia at Deep Space Station (DSS) 41, established in August 1960. The Island Lagoon site was the first deep space station to be established outside the United States and the first Australian antenna NASA built. The station was operated by the Australian Department of Supply and helped support the Ranger and early Mariner missions, as well as communications from the Deep Space Network (DSN) complex in Goldstone, California via a moon bounce. Woomera’s antenna ceased operations in 1972.
Today, the Deep Space Network -- consisting of three sites in Goldstone, California; Madrid, Spain; and Canberra, Australia -- supports space communications for NASA and non-NASA missions that explore the furthest points of our solar system. Each complex currently has a 70 meter (230 foot) antenna, one 34 meter (111 foot) High Efficiency (HEF) antenna, and one or more 34 meter Beam Wave Guide (BWG) antenna. The Deep Space Network is operated 24 hours a day, seven days a week, 365 days per year. To support future mission needs, construction is currently underway in Canberra, Australia to add two new 34 meter BWG antennas, Deep Space Station 35 (DSS-35) and DSS-36 by 2018.
Engineers document cargo as it is unloaded from the Soyuz TMA-10M spacecraft after it landed with Expedition 38 Commander Oleg Kotov of the Russian Federal Space Agency, Roscosmos, and Flight Engineers: Mike Hopkins of NASA, and, Sergey Ryazanskiy of Roscosmos, near the town of Zhezkazgan, Kazakhstan on Tuesday, March 11, 2014. Hopkins, Kotov and Ryazanskiy returned to Earth after five and a half months onboard the International Space Station where they served as members of the Expedition 37 and 38 crews.
Hubble Celebrates 24th Anniversary with Infrared Image of Nearby Star Factory
In celebration of the 24th anniversary of the launch of NASA's Hubble Space Telescope, astronomers have captured infrared-light images of a churning region of star birth 6,400 light-years away.
This colorful Hubble Space Telescope mosaic of a small portion of the Monkey Head Nebula unveils a collection of carved knots of gas and dust silhouetted against glowing gas. The cloud is sculpted by ultraviolet light eating into the cool hydrogen gas.
Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
This esthetic close-up of cosmic clouds and stellar winds features LL Orionis, interacting with the Orion Nebula flow. Adrift in Orion's stellar nursery and still in its formative years, variable star LL Orionis produces a wind more energetic than the wind from our own middle-aged Sun. As the fast stellar wind runs into slow moving gas a shock front is formed, analogous to the bow wave of a boat moving through water or a plane traveling at supersonic speed.
The small, arcing, graceful structure just above and left of center is LL Ori's cosmic bow shock, measuring about half a light-year across. The slower gas is flowing away from the Orion Nebula's hot central star cluster, the Trapezium, located off the upper left corner of the picture. In three dimensions, LL Ori's wrap-around shock front is shaped like a bowl that appears brightest when viewed along the "bottom" edge. The beautiful picture is part of a large mosaic view of the complex stellar nursery in Orion, filled with a myriad of fluid shapes associated with star formation.
Image Credit: NASA, ESA and the Hubble Heritage Team
NASA Releases First Interactive Mosaic of Lunar North Pole
Scientists, using cameras aboard NASA's Lunar Reconnaissance Orbiter (LRO), have created the largest high resolution mosaic of our moon’s north polar region. The six-and-a-half feet (two-meters)-per-pixel images cover an area equal to more than one-quarter of the United States.
The images making up the mosaic were taken by the two LRO Narrow Angle Cameras, which are part of the instrument suite known as the Lunar Reconnaissance Orbiter Camera (LROC). The cameras can record a tremendous dynamic range of lit and shadowed areas.
Web viewers can zoom in and out, and pan around an area. Constructed from 10,581 pictures, the mosaic provides enough detail to see textures and subtle shading of the lunar terrain. Consistent lighting throughout the images makes it easy to compare different regions.
