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Saturday, October 8, 2011

Comet Hartley 2: The Same Here as There


New measurements from the Herschel Space Observatory have discovered water with the same chemical signature as our oceans in a comet called Hartley 2 (pictured at right). Previously, astronomers thought icy comets impacting on a young Earth had deposited only about 10 percent of the water comprising our oceans. The new findings, however, suggest that comets played a much bigger role.

The image of Comet Hartley 2 at top right was taken by NASA's EPOXI mission. The image at bottom right is an artist's concept of a comet.

Using the Herschel Space Observatory, astronomers have discovered that Comet Hartley 2 possesses a ratio of "heavy water" to light, or normal, water that matches what's found in Earth's oceans. In heavy water, one of the two hydrogen atoms has been replaced by the heavy hydrogen isotope known as deuterium. Hartley 2 contains half as much heavy water as other comets analyzed to date. Herschel's "Heterodyne Instrument for the Far Infrared," or HIFI, was used to obtain the spectral signatures of the water molecules, as shown here in the graphs.

The image of Comet Harley 2 was taken by NASA's EPOXI mission.

Image credit: NASA/JPL-Caltech

Note: For more information, see Herschel Finds First Evidence of Earth-Like Water in a Comet; also, PIA14737: Heavy and Light Just Right.

Friday, October 7, 2011

Curiosity All Dressed Up And Someplace To Go


At the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center in Florida, the Mars Science Laboratory rover, Curiosity, and the spacecraft's descent stage have been enclosed inside the spacecraft's aeroshell.

This image, taken October 1, 2011, shows the aeroshell with its heat shield on top.

The heat shield and the spacecraft's back shell together form the encapsulating aeroshell that will protect the rover from the intense heat that will be generated as the flight system descends through the Martian atmosphere.

The mission is on track for launch from Cape Canaveral Air Force Station during the period from November 25 to December 18, 2011.

Photo credit: NASA/JPL-Caltech

Thursday, October 6, 2011

NGC 4038 and 4039 - The Antennae Galaxies


The Antennae Galaxies (also known as NGC 4038 and 4039) are a pair of distorted colliding spiral galaxies about 70 million light-years away, in the constellation of Corvus (The Crow). This view combines ALMA observations, made in two different wavelength ranges during the observatory’s early testing phase, with visible-light observations from the NASA/ESA Hubble Space Telescope.

The Hubble image is the sharpest view of this object ever taken and serves as the ultimate benchmark in terms of resolution. ALMA observes at much longer wavelengths which makes it much harder to obtain comparably sharp images. However, when the full ALMA array is completed its vision will be up to ten times sharper than Hubble.

Most of the ALMA test observations used to create this image were made using only twelve antennas working together — far fewer than will be used for the first science observations — and much closer together as well. Both of these factors make the new image just a taster of what is to come. As the observatory grows, the sharpness, speed, and quality of its observations will increase dramatically as more antennas become available and the array grows in size. This is nevertheless the best sub-millimeter-wavelength image ever taken of the Antennae Galaxies and opens a new window on the sub-millimeter Universe.

While visible light — shown here mainly in blue — reveals the newborn stars in the galaxies, ALMA’s view shows us something that cannot be seen at those wavelengths: the clouds of dense cold gas from which new stars form. The ALMA observations — shown here in red, pink and yellow — were made at specific wavelengths of millimeter and sub-millimeter light (ALMA bands 3 and 7), tuned to detect carbon monoxide molecules in the otherwise invisible hydrogen clouds, where new stars are forming.

Massive concentrations of gas are found not only in the hearts of the two galaxies but also in the chaotic region where they are colliding. Here, the total amount of gas is billions of times the mass of the Sun — a rich reservoir of material for future generations of stars. Observations like these will be vital in helping us understand how galaxy collisions can trigger the birth of new stars. This is just one example of how ALMA reveals parts of the Universe that cannot be seen with visible-light and infrared telescopes.

Photo credit: ALMA (ESO/NAOJ/NRAO). Visible light image: the NASA/ESA Hubble Space Telescope

Note: For more information (and many more photographs), see ALMA Opens Its Eyes.

Wednesday, October 5, 2011

Saturn's Lengthening Shadows


The Cassini spacecraft watches as the shadows of Saturn's rings grow wider and creep farther south as the seasons progress from the planet's August 2009 equinox.

See PIA11667 to learn more about the changing seasons and to see a view from equinox when the rings cast only a thin shadow on Saturn's equator. See PIA09793 for an even earlier view of the rings' wide shadows draped high on the northern hemisphere.

This view looks toward the northern, sunlit side of the rings from just above the ringplane.

The image was taken with the Cassini spacecraft wide-angle camera on August 22, 2011 using a spectral filter sensitive to wavelengths of near-infrared light centered at 939 nanometers. The view was acquired at a distance of approximately 252,000 miles (405,000 kilometers) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 140 degrees. Image scale is 13 miles (21 kilometers) per pixel.

Photo credit: NASA/JPL-Caltech/Space Science Institute

Tuesday, October 4, 2011

Rocas Coloridas en Terra Sabaea


Esta zona de las antiguas tierras altas australes ha sido modificada por la tectónica, es decir, por fallas y pliegues que afectan a las unidades de roca.

Esta imagen también es interesante vista a través de los colores de la HiRISE. Estos (mejorados en la subimagen) indican la variedad de minerales que hay presentes. Esta región fue objetivo del CRISM para estudiar con más detalle la detección de olivino que se había hecho previamente. El olivino, un mineral volcánico, da los colores verdes y azules que se aprecian en la imagen de la HiRISE.

Colorful Rocks in Terra Sabaea

This area of ​​the ancient southern highlands has been modified by tectonics, i.e., faults and folds that affect the rock units.

This image is also interesting view through the colors of the HiRISE. These (enhanced in the subpicture) indicate the variety of minerals that are present. This region was the target of CRISM to study in more detail the detection of olivine that had been done previously. Olivine, a volcanic mineral, giving the green and blue colors that are seen in the HiRISE image.

Photo credit: NASA/JPL/La Universidad de Arizona

Note: This location is about halfway between Hellas Planitia (which is due south) and Harris Crater, which is slightly to the north-northeast.

Monday, October 3, 2011

Holmberg II


The NASA/ESA Hubble Space Telescope has captured this image of dwarf irregular galaxy Holmberg II. The galaxy is dominated by huge bubbles of glowing gas, which are sites of ongoing star formation.

As high-mass stars form in dense regions of gas and dust they expel strong stellar winds that blow away the surrounding material. The cavities are also blown clear of gas by the shock waves produced in supernovae, the violent explosions that mark the end of the lives of massive stars.

Photo credit: NASA/ESA

Note: For more information, see Galaxy caught blowing bubbles.

Sunday, October 2, 2011

Changing Views of Our Solar System



This animation illustrates new results from NASA's Wide-field Infrared Survey Explorer, or WISE, taken during its one-year survey of the sky in infrared light. The asteroid-hunting portion of the mission, called NEOWISE, scanned for asteroids both in the main belt between Mars and Jupiter, and those near Earth. The observations led to a reduced estimate of the total population of medium to large-sized near-Earth asteroids (objects larger than 330 feet or 100 meters).

The movie begins by showing a simulated view of the estimated population before the NEOWISE survey, depicted in red. Each dot represents one asteroid. Object sizes are not to scale. At that time, the best models for the entire population, based on visible-light surveys, indicated roughly 36,000 members.

The movie then reveals known asteroids in orange. About 5,200 near-Earth asteroids larger than 330 feet have already been discovered. Next, the blue dots show which asteroids NEOWISE observed, and the white dots are those the project discovered. The NEOWISE telescope observed more than 500 of these space rocks, including the newfound ones.

The animation also illustrates how NEOWISE was able to capture a slice of the near-Earth asteroid population. The telescope orbited the poles of Earth, continuously taking snapshots of the sky at 90-degree angles from the Sun. As Earth orbited around the Sun, WISE detected more and more near-Earth asteroids. It also saw more than 150,000 asteroids in the main belt between Mars and Jupiter, which are not shown here.

From these data, the science team was able to make the most accurate estimates to date of what the entire near-Earth asteroid population looks like. The next part of the movie shows what the mission found -- fewer total numbers. The NEOWISE observations indicate that there are about 20,500 near-Earth asteroids in total that are larger than 330 feet -- 43 percent less than previous estimates of 36,000.

Video credit: NASA/JPL-Caltech

Note: A number of related videos and illustrations have been released in addition to the one above. For more information, see PIA14732: Infrared Telescopes Spy Small, Dark Asteroids, PIA14733: How to Tell the Size of An Asteroid, PIA14734: WISE Revises Numbers of Asteroids Near Earth, and PIA14736: Portrait of Two Asteroids in Different Light.

Saturday, October 1, 2011

China Launches First Module for Space Station



China launched the first module of what may ultimately become that country's first space station. The module, Tiangong-1 (Heavenly Palace-1), was launched from the Jiuquan Satellite Launch Center on Thursday, September 29th. The module, the first of three, is designed to test rendezvous and orbital docking capabilities for the ultimate goal of creating a 20-ton multi-module space station, scheduled to begin construction around the year 2020. Tiangong-1 is scheduled to be visited by three Shenzhou missions within the next year, and has room for two astronauts to sleep on-board the spacecraft.

For a variety of global opinions about the launch of Tiangong-1, see:
BBC: Tiangong rocket: China media reacts to space launch
CNN: China's Space Ambition Soars
International Business Times: Developing Nations Working Toward China’s Space Success
People's Daily Online: China's space station realizes 'rendezvous, docking' of dreams, reality
The Guardian: China space station signals shift in space race

Video credit: Al-Jazeera English

Friday, September 30, 2011

NGC 281 - The Pacman Nebula


High-mass stars are important because they are responsible for much of the energy pumped into our galaxy over its lifetime. Unfortunately, these stars are poorly understood because they are often found relatively far away and can be obscured by gas and dust. The star cluster NGC 281 is an exception to this rule. It is located about 6,500 light years from Earth and, remarkably, almost 1,000 light years above the plane of the galaxy, giving astronomers a nearly unfettered view of the star formation within it.

This composite image of NGC 281 contains X-ray data from Chandra, in purple, with infrared observations from Spitzer, in red, green, blue. The high-mass stars in NGC 281 drive many aspects of their galactic environment through powerful winds flowing from their surfaces and intense radiation that creates charged particles by stripping electrons off atoms. The eventual deaths of massive stars as supernovas will also seed the galaxy with material and energy.

NGC 281 is known informally as the "Pacman Nebula" because of its appearance in optical images. In optical images the "mouth" of the Pacman character appears dark because of obscuration by dust and gas, but in the infrared Spitzer image the dust in this region glows brightly.

NGC 281 is typically divided into two subregions: the region in the upper middle of the image, which is surrounded by the purple 10-million-degree gas, and a younger region in the lower part of the image. There is evidence that the formation of a cluster, appearing in a beige cloud to the lower right, was triggered by a previous generation of star formation. Also, astronomers have found some isolated star formation on the left side of the image that appears to have been occurring at the same time as star formation in other regions of the cluster. This supports the idea that something externally triggered the "baby boom" of stars in NGC 281.

Photo credit: X-ray: NASA/CXC/CfA/S.Wolk; IR: NASA/JPL/CfA/S.Wolk

Note: For more information, see NGC 281: Living the High Life.

Thursday, September 29, 2011

The Fried Egg Nebula


This picture of the nebula around a rare yellow hypergiant star called IRAS 17163-3907 is the best ever taken of a star in this class and shows for the first time a huge dusty double shell surrounding the central hypergiant. The star and its shells resemble an egg white around a yolky center, leading astronomers to nickname the object the Fried Egg Nebula.

Photo credit: ESO/E. Lagadec

Note: For more information, see Feast Your Eyes on the Fried Egg Nebula.

Wednesday, September 28, 2011

Shangri-La of Titan


Saturn's rings lie in the distance as the Cassini spacecraft looks toward Titan and its dark region called Shangri-La, east of the landing site of the Huygens Probe.

See PIA06136 and PIA09739 and PIA08137 to learn more about Titan's atmosphere.

Photo credit: NASA/JPL-Caltech/Space Science Institute

Tuesday, September 27, 2011

The Origin of Ultrafast Substorm Auroras



This animation depicts the sequence of events that give rise to ultrafast substorm auroras.

A magnetic reconnection event occurs far out in the magnetotail, at a distance of around 125,000 - 200,000 km.

Energy from this event is transported by kinetic Alfvén waves (KAW) - which carry electrons - towards Earth at speeds of several thousand kilometers per second.

These KAW can reach Earth quickly enough, and carry sufficient energy, to produce intense auroras.

In reality, the reconnection process is persistent and less bursty, continuously emitting energy via the KAWs to the aurora.

Video credit: ESA/AOES Medialab

Note: For more information, see Ultrafast Substorm Auroras Explained.

Monday, September 26, 2011

The Thirty Meter Telescope (TMT)

The Minister was watching this week's episode of Science Zero on NHK World this morning, which happened to be about the proposed Thirty Meter Telescope (TMT). If built, the TMT will have a collective primary mirror that is 30 meters wide and an area of 655 square meters. By "collective," the Minister means that the primary mirror will be segmented, composed of 492 individual hexagonal mirrors that are each 1.4 meters across. If built, the TMT will gather its first light in October 2017, with scientific operations starting in June 2018.

Below are two videos that have been produced about the TMT, providing more information about the telescope and what astronomers hope to be able to achieve with it.




Youtube Link



Youtube Link

Sunday, September 25, 2011

Dust Shells in IRC+10216


New images of IRC+10216, obtained with the PACS instrument on the Herschel Space Observatory, have revealed never before seen dust shells extending out to a distance of 320 arc seconds from the central star.

This image was obtained at 100 micron and shows a field of view of 16 arc minutes × 11 arc minutes.

The 6 radial spikes are due to the support structure of the secondary mirror.

Photo credit: ESA/PACS/MESS Consortia

Notes: For an annotated version of the above image, see here. For more information, see Herschel Probes the Dusty History of a Giant Star. IRC+10216, aka CW Leonis, has been discussed on MinSEx before; see Water Around CW Leonis.

Saturday, September 24, 2011

Ocean Salinity by Aquarius


NASA's new Aquarius instrument has produced its first global map of the salinity, or saltiness, of Earth's ocean surface, providing an early glimpse of the mission's anticipated discoveries. Its rich tapestry of global salinity patterns demonstrates Aquarius' ability to resolve large-scale salinity distribution features clearly and with sharp contrast. The map provides a much better picture of ocean surface salinity than the Aquarius science team expected to have this early in the mission.

The new map is a composite of the first two and a half weeks of data since Aquarius became operational on August 25. The numerical values represent salt concentration in parts per thousand (grams of salt per kilogram of sea water). Yellow and red colors represent areas of higher salinity, with blues and purples indicating areas of lower salinity. Areas colored black are gaps in the data. The average salinity on the map is about 35.

The map reveals predominantly well-known ocean salinity features, such as higher salinity in the subtropics, higher average salinity in the Atlantic Ocean compared to the Pacific and Indian Oceans, and lower salinity in rainy belts near the equator, in the northernmost Pacific Ocean and elsewhere. These features are related to large-scale patterns of rainfall and evaporation over the ocean, river outflow and ocean circulation. Aquarius will monitor how these features change over time and study their link to climate and weather variations.

Other important regional features are clearly evident, including a sharp contrast between the arid, high-salinity Arabian Sea west of the Indian subcontinent, and the low-salinity Bay of Bengal to the east, which is dominated by the Ganges River and south Asia monsoon rains. The data also show important smaller details, such as a larger-than-expected extent of low-salinity water associated with outflow from the Amazon River.

To produce the map, Aquarius scientists performed a preliminary calibration of the early data gathered by comparing them with ocean surface salinity reference data. These early data contain some uncertainties, and months of additional calibration and data validation work remain. For example, measurements in the southernmost ocean regions are not yet reliable as they have large uncertainties associated with high winds and low surface temperatures. The north-south striped patterns visible throughout the image are artifacts of small residual calibration errors and are not real. In addition, low salinity values immediately adjacent to land and ice-covered areas are due to proximity to coastlines or ice edges, which introduces errors into the data that will require additional analyses to correct.

Image credit: NASA/GSFC/JPL-Caltech

Friday, September 23, 2011

The Spectrum of a Star That Should Not Exist


This picture shows the distribution of the light of different colors coming from the remarkable star SDSS J102915+172927 after it has been split up by the X-Shooter instrument on the ESO VLT. Different colors fall in different places in this strange picture and astronomers can use this data to find the chemical signals from different elements within the star, which show up as dark interruptions of the curved lines. The spectrum of the star appears to be triple at each wavelengths as it was split up using an integral field unit to collect as much light as possible. This ancient star has been found to have the lowest amount of elements heavier than helium of all stars yet studied. The only evidence of elements heavier than helium is two dark lines from the element calcium.

Photo credit: ESO/E. Caffau

Note: For more information, see The Star That Should Not Exist.

Thursday, September 22, 2011

The Running Chicken Nebula


This new image from the Wide Field Imager on the MPG/ESO 2.2-meter telescope shows the Running Chicken Nebula, a cloud of gas and newborn stars that lies around 6500 light-years away from us in the constellation of Centaurus (The Centaur). Officially called IC 2944, or the Lambda Centauri Nebula, its strange nickname comes from the bird-like shape of its brightest region. The star Lambda Centauri itself lies just outside the field of view.

Photo credit: ESO

Notes: The Minister has blogged about the Running Chicken Nebula before; see Chasing Chickens in the Lambda Centauri Nebula. For more information, see An Angry Bird in the Sky.

Wednesday, September 21, 2011

Flying Over the Earth



A rare time-lapse clip showing a bird’s-eye view of our planet from outer space in one minute has surfaced on the Web.

The video shows a collection of 600 images downloaded from NASA’s astronaut database and merged together by science blogger James Drake.

During the clip, storms over the Pacific Ocean, the Earth’s ionosphere (thin yellow line) and the stars in our galaxy are illustrated as the International Space Station (ISS) orbits the Earth.

Heavily populated urban areas can be seen beautifully lit up in the dark of night.

The 62-second montage begins over the Pacific Ocean at an altitude of 220 miles and continues over North and South America before sunrise near Antarctica.

Mr. Drake notes in order of appearance a few of the places that can be seen in the stunning clip, including Vancouver Island, Victoria, Vancouver, Seattle, Portland, San Francisco, Los Angeles, Arizona, Texas, New Mexico, Mexico City, the Gulf of Mexico, the Yucatan Peninsula, Guatemala, Panama, Colombia, Ecuador, the Amazon, Peru and Chile.

The images were hand-picked from the Gateway to Astronaut Photography of Earth which contains over a million snaps of the planet dating back to the 1960’s.

Text credit: Yahoo! News; video credit: NASA/James Drake

Tuesday, September 20, 2011

NGC 2100


The brilliant star cluster NGC 2100 lies in the Large Magellanic Cloud, a small satellite galaxy of the Milky Way. This image was taken with the EMMI instrument on the ESO New Technology Telescope (NTT) at the La Silla Observatory in Chile. This star cluster lies close to the Tarantula Nebula and some of the colorful outer parts of the nebula appear in this image. The smaller cluster, close to the right-hand edge of the picture and just below center, is NGC 2092.

Photo credit: ESO

Note: For more information, see Young Stars Take a Turn in the Spotlight.

Monday, September 19, 2011

Into the Depths of the Lagoon Nebula


Swirling dust clouds and bright newborn stars dominate the view in this image of the Lagoon nebula from NASA's Spitzer Space Telescope. Also known as Messier 8 and NGC 6523, astronomers estimate it to be between 4000 and 6000 light years away, lying in the general direction of the center of our galaxy in the constellation Sagittarius.

The Lagoon nebula was first noted by the astronomer Guillaume Le Gentil in 1747, and a few decades later became the 8th entry in Charles Messier's famous catalog of nebulae. It is of particular interest to stargazers as it is only one of two star-forming nebulae that can be seen with the naked eye from northern latitudes, appearing as a fuzzy grey patch.

The glowing waters of the Lagoon, as seen in visible light, are really pools of hot gas surrounding the massive, young stars found here. Spitzer's infrared vision looks past the gas to show the dusty basin that it fills. Here we see the central regions of the Lagoon with green showing the glow of carbon-based dust grains, and red highlighting the thermal glow of the hottest dust.

The various columns of dust all seem to point inwards towards the central depths of the Lagoon. These structures are being sculpted by the intense glow of giant, young stars found at the nebula's core. Within these clouds of dust and gas, a new generation of stars is forming.

This image was made using data from Spitzer's Infrared Array Camera (IRAC). Blue shows infrared light with wavelengths of 3.6 microns, green represents 4.5-micron light and red, 8.0-micron light.

Photo credit: NASA/JPL-Caltech

Sunday, September 18, 2011

Journey Above Vesta



A new video from NASA's Dawn spacecraft takes us on a flyover journey above the surface of the giant asteroid Vesta.

The data obtained by Dawn's framing camera, used to produce the visualizations, will help scientists determine the processes that formed Vesta's striking features. It will also help Dawn mission fans all over the world visualize this mysterious world, which is the second most massive object in the main asteroid belt.

The video, which shows Vesta as seen from Dawn's perspective, can be viewed at: http://www.jpl.nasa.gov/video/index.cfm?id=1020.

You'll notice in the video that Vesta is not entirely lit up. There is no light in the high northern latitudes because, like Earth, Vesta has seasons. Currently it is northern winter on Vesta, and the northern polar region is in perpetual darkness. When we view Vesta's rotation from above the south pole, half is in darkness simply because half of Vesta is in daylight and half is in the darkness of night .

Another distinct feature seen in the video is a massive circular structure in the south pole region. Scientists were particularly eager to see this area close-up, since NASA's Hubble Space Telescope first detected it years ago. The circular structure, or depression, is several hundreds of miles, or kilometers, wide, with cliffs that are also several miles high. One impressive mountain in the center of the depression rises approximately 9 miles (15 kilometers) above the base of this depression, making it one of the highest elevations on all known bodies with solid surfaces in the solar system.

The collection of images, obtained when Dawn was about 1,700 miles (2,700 kilometers) above Vesta's surface, was used to determine its rotational axis and a system of latitude and longitude coordinates. One of the first tasks tackled by the Dawn science team was to determine the precise orientation of Vesta's rotation axis relative to the celestial sphere.

The zero-longitude, or prime meridian, of Vesta was defined by the science team using a tiny crater about 1,640 feet (500 meters) in diameter, which they named "Claudia," after a Roman woman during the second century B.C. Dawn's craters will be named after the vestal virgins-the priestesses of the goddess Vesta, and famous Roman women, while other features will be named for festivals and towns of that era.

Video credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Saturday, September 17, 2011

NASA's Kepler Discovery Confirms First Planet Orbiting Two Stars



The existence of a world with a double sunset, as portrayed in the film Star Wars more than 30 years ago, is now scientific fact. NASA's Kepler mission has made the first unambiguous detection of a circumbinary planet -- a planet orbiting two stars -- 200 light-years from Earth.

Unlike Star Wars’ Tatooine, the planet is cold, gaseous and not thought to harbor life, but its discovery demonstrates the diversity of planets in our galaxy. Previous research has hinted at the existence of circumbinary planets, but clear confirmation proved elusive. Kepler detected such a planet, known as Kepler-16b, by observing transits, where the brightness of a parent star dims from the planet crossing in front of it.

"This discovery confirms a new class of planetary systems that could harbor life,” Kepler principal investigator William Borucki said. “Given that most stars in our galaxy are part of a binary system, this means the opportunities for life are much broader than if planets form only around single stars. This milestone discovery confirms a theory that scientists have had for decades but could not prove until now."

A research team led by Laurance Doyle of the SETI Institute in Mountain View, California, used data from the Kepler space telescope, which measures dips in the brightness of more than 150,000 stars, to search for transiting planets. Kepler is the first NASA mission capable of finding Earth-size planets in or near the "habitable zone," the region in a planetary system where liquid water can exist on the surface of the orbiting planet.

Scientists detected the new planet in the Kepler-16 system, a pair of orbiting stars that eclipse each other from our vantage point on Earth. When the smaller star partially blocks the larger star, a primary eclipse occurs, and a secondary eclipse occurs when the smaller star is occulted, or completely blocked, by the larger star.

Astronomers further observed that the brightness of the system dipped even when the stars were not eclipsing one another, hinting at a third body. The additional dimming in brightness events, called the tertiary and quaternary eclipses, reappeared at irregular intervals of time, indicating the stars were in different positions in their orbit each time the third body passed. This showed the third body was circling, not just one, but both stars, in a wide circumbinary orbit.

The gravitational tug on the stars, measured by changes in their eclipse times, was a good indicator of the mass of the third body. Only a very slight gravitational pull was detected, one that only could be caused by a small mass. The findings are described in a new study published Friday, September 16, in the journal Science.

"Most of what we know about the sizes of stars comes from such eclipsing binary systems, and most of what we know about the size of planets comes from transits," said Doyle, who also is the lead author and a Kepler participating scientist. "Kepler-16 combines the best of both worlds, with stellar eclipses and planetary transits in one system."

This discovery confirms that Kepler-16b is an inhospitable, cold world about the size of Saturn and thought to be made up of about half rock and half gas. The parent stars are smaller than our sun. One is 69 percent the mass of the sun and the other only 20 percent. Kepler-16b orbits around both stars every 229 days, similar to Venus’ 225-day orbit, but lies outside the system’s habitable zone, where liquid water could exist on the surface, because the stars are cooler than our sun.

"Working in film, we often are tasked with creating something never before seen," said visual effects supervisor John Knoll of Industrial Light & Magic, a division of Lucasfilm Ltd., in San Francisco. "However, more often than not, scientific discoveries prove to be more spectacular than anything we dare imagine. There is no doubt these discoveries influence and inspire storytellers. Their very existence serves as cause to dream bigger and open our minds to new possibilities beyond what we think we 'know.'"

Text credit: NASA/Ames Research Center

Video credit: NASA/Ames Research Center

Friday, September 16, 2011

Chester Lake


An outcrop informally named "Chester Lake" is the second rock on the rim of Endeavour crater to be approached by NASA's Mars Exploration Rover Opportunity for close inspection with instruments on the rover's robotic arm. This view of Chester Lake combines images taken through three different filters by Opportunity's panoramic camera (Pancam) and is presented in false color to emphasize differences among materials in the rock and soil. The component images were taken during the 2,709th Martian day, or sol, of Opportunity's work on Mars (September 7, 2011).

Chester Lake is about 3 feet (1 meter) across. It lies on the inboard (southeastern) side of a low ridge, "Cape York," which forms a portion of the western rim of Endeavour crater. Rover team scientists chose it for inspection because it is in-place bedrock that appears to be representative of a region of outcrops on the inboard side of Cape York.

Chester Lake differs from the first rock inspected by Opportunity on the Endeavour rim, "Tisdale 2," which is a boulder excavated during an impact event that produced a small crater on the rim. Both rocks appear to be breccia, a type of rock fusing together broken fragments of older rocks. By Sol 2713 (September 11, 2011), researchers had used Opportunity's microscopic imager and alpha particle X-ray spectrometer to study Chester Lake and were planning to use the rover's rock abrasion tool and, possibly, its Moessbauer spectrometer on the rock. They will use all the data to reconstruct the chemistry, mineralogy and geologic setting of Chester Lake, including evidence about whether or not the rock has any clay minerals in its composition.

Images combined into this view were taken through Pancam filters admitting light with wavelengths centered at 753 nanometers (near infrared), 535 nanometers (green) and 432 nanometers (violet).

Photo credit: NASA/JPL-Caltech/Cornell/ASU

Note: For two other pictures of Chester Lake, see PIA14751: Shadow Across 'Chester Lake' on Endeavour Rim, Sol 2710 and PIA14753: 'Chester Lake' Bedrock on Rim of Endeavour Crater.

Thursday, September 15, 2011

Artist's Impression of a Gently-Forming Galaxy


This illustration shows a galaxy which is accreting mass from rapid, narrow streams of cold gas. These filaments provide the galaxy with a continuous flow of raw material to support its star-forming activity at a rather leisurely pace.

This theoretical scenario for galaxy formation is based on the numerical simulations presented by Dekel et al., 2009 (Nature, 457, 451D). However, the actual process of stream accretion onto a galaxy has never been directly observed to date and the scenario remains only speculative.

Illustration credit: ESA/AOES Medialab

Note: For more information, see Herschel Reveals How Most Stars Formed in the Universe.

Wednesday, September 14, 2011

Super-Earth Planet HD 85512b



This animation shows an artist’s impression the planet orbiting the Sun-like star HD 85512 in the southern constellation of Vela (The Sail). This planet is one of sixteen super-Earths discovered by the HARPS instrument on the 3.6-meter telescope at ESO’s La Silla Observatory. This planet is about 3.6 times as massive as the Earth and lies at the edge of the habitable zone around the star, where liquid water, and perhaps even life, could potentially exist.

Video credit: ESO/M. Kornmesser

Note: For more information, see Fifty New Exoplanets Discovered by HARPS.

Saturday, September 10, 2011

Vesta in Visible and Infrared Light


NASA's Dawn spacecraft obtained these images with its visible and infrared instrument on July 23, 2011. The two images represent the same zone of the giant asteroid Vesta with an image resolution of 1.3 kilometers per pixel.

The top image is a simulated true-color picture of the asteroid's surface to show what it would like to the human eye. The image was produced by assigning visible-light colors (blue, green and red) to three visible and infrared channels (440, 550 and 700 nanometers).

In the bottom image, visible and infrared channels have again been assigned visible-light colors. But in this case, the colors were chosen to enhance the differences in the composition of the asteroid surface and, therefore, in the geologic processes that must have created them.

Photo credit: NASA/JPL-Caltech/UCLA/ASI/INAF/IASF/IFSI

Monday, September 5, 2011

Herbig-Haro Objects in the Orion Complex


This image from the Kitt Peak National Observatory (KPNO) 4-meter telescope shows a roughly 1/2-degree square region of the sky in the constellation of Orion (about the same size as the diameter of the full Moon). This is a small part of the Orion Molecular Cloud Complex, a giant region of gas and dust undergoing active star formation some 1,500 light-years away.

Numerous small knots known as Herbig-Haro Objects, labeled here in white, are signatures of recently formed stars ejecting material into space. The three HH objects labeled in green have been subjects of intense study by the NASA/ESA Hubble Space Telescope over several years, resulting in a better understanding of how the material ejected from stars interacts with the surrounding medium.

Photo credit: Z. Levay (STScI), T.A. Rector (University of Alaska Anchorage), and H. Schweiker (NOAO/AURA/NSF)

Sunday, September 4, 2011

Stellar Jets HH 47, HH 34 and HH 2


The glowing, clumpy streams of material shown in these NASA/ESA Hubble Space Telescope images are the signposts of star birth.

Ejected episodically by young stars like cannon salvos, the blobby material zips along at more than 700,000 kilometers per hour. The speedy jets are confined to narrow beams by the powerful stellar magnetic field. Called Herbig-Haro or HH objects, these outflows have a bumpy ride through space.

When fast-moving blobs collide with slower-moving gas, bow shocks arise as the material heats up. Bow shocks are glowing waves of material similar to waves produced by the bow of a ship ploughing through water.

In HH 2, at lower right, several bow shocks can be seen where several fast-moving clumps have bunched up like cars in a traffic jam. In HH 34, at lower left, a grouping of merged bow shocks reveals regions that brighten and fade over time as the heated material cools where the shocks intersect.

In HH 47, at top, the blobs of material look like a string of cars on a crowded motorway, which ends in a chain-reaction accident. The smash up creates the bow shock, left.

These images are part of a series of time-lapse movies astronomers have made showing the outflows' motion over time. The movies were stitched together from images taken over a 14-year period by Hubble's Wide Field Planetary Camera 2. Hubble followed the jets over three epochs: HH 2 from 1994, 1997, and 2007; HH 34 from 1994, 1998, and 2007; and HH 47 from 1994, 1999, and 2008.

The outflows are roughly 1350 light-years from Earth. HH 34 and HH 2 reside near the Orion Nebula, in the northern sky. HH 47 is located in the southern constellation of Vela.

Photo credit: NASA, ESA, and P. Hartigan (Rice University)

Note: For more information, see Hubble Movies Provide Unprecedented View of Supersonic Jets from Young Stars.


Saturday, September 3, 2011

Tisdale 2


This rock, informally named "Tisdale 2," was the first rock the NASA's Mars Rover Opportunity examined in detail on the rim of Endeavour crater. It has textures and composition unlike any rock the rover examined during its first 90 months on Mars. Its characteristics are consistent with the rock being a breccia -- a type of rock fusing together broken fragments of older rocks. Tisdale 2 is about 12 inches (30 centimeters) tall.

Photo credit: NASA/JPL-Caltech/Cornell/Arizona State University

Note: A number of other photos have been released with regard to Tisdale 2; see PIA14745: Locations of Microscopic Imager Observations on 'Tisdale 2', PIA14746: Magnified View of Texture on Part of "Tisdale 2" Rock, PIA14747: Elevated Zinc and Bromine in Rock on Endeavour Rim, PIA14748: Approaching 'Tisdale 2' Rock on Rim of Endeavour Crater, Sol 2690, and PIA14749: Opportunity at Work Examining 'Tisdale 2,' Sol 2695.

Friday, September 2, 2011

Earth and Moon, by Juno


On its way to the biggest planet in the solar system -- Jupiter, NASA's Juno spacecraft took time to capture its home planet and its natural satellite -- the Moon.

"This is a remarkable sight people get to see all too rarely," said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. "This view of our planet shows how Earth looks from the outside, illustrating a special perspective of our role and place in the universe. We see a humbling yet beautiful view of ourselves."

The image was taken by the spacecraft’s camera, JunoCam, on August 26 when the spacecraft was about 6 million miles (9.66 million kilometers) away. The image was taken as part of the mission team’s checkout of the Juno spacecraft. The team is conducting its initial detailed checks on the spacecraft’s instruments and subsystems after its launch on August 5.

Juno covered the distance from Earth to the Moon (about 250,000 miles or 402,000 kilometers) in less than one day's time. It will take the spacecraft another five years and 1,740 million miles (2,800 million kilometers) to complete the journey to Jupiter. The spacecraft will orbit the planet's poles 33 times and use its eight science instruments to probe beneath the gas giant's obscuring cloud cover to learn more about its origins, structure, atmosphere and magnetosphere, and look for a potential solid planetary core.

The solar-powered Juno spacecraft lifted off from Cape Canaveral Air Force Station in Florida at 9:25 a.m. PDT (12:25 p.m. EDT) on August 5 to begin its five-year journey to Jupiter.

Photo credit: NASA/JPL-Caltech

Thursday, September 1, 2011

The Necklace Nebula


A giant cosmic necklace glows brightly in this NASA Hubble Space Telescope image.

The object, aptly named the Necklace Nebula, is a recently discovered planetary nebula, the glowing remains of an ordinary, Sun-like star. The nebula consists of a bright ring, measuring 12 trillion miles across, dotted with dense, bright knots of gas that resemble diamonds in a necklace. The knots glow brightly due to absorption of ultraviolet light from the central stars.

A pair of stars orbiting very close together produced the nebula, also called PN G054.2-03.4. About 10,000 years ago one of the aging stars ballooned to the point where it enveloped its companion star. This caused the larger star to spin so fast that much of its gaseous envelope expanded into space. Due to centrifugal force, most of the gas escaped along the star's equator, producing a dense ring. The embedded bright knots are the densest gas clumps in the ring.

The stars are furiously whirling around each other, completing an orbit in a little more than a day. (For comparison, Mercury, the closest planet to the Sun, takes 88 days to orbit the Sun.)

The Necklace Nebula is located 15,000 light-years away in the constellation Sagitta (the Arrow). In this composite image, taken on July 2, 2011, Hubble's Wide Field Camera 3 captured the glow of hydrogen (blue), oxygen (green), and nitrogen (red).

Photo credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)