Europe's Cupola provides astronauts on the International Space Station with a panoramic view of Earth. Here STS-130 mission specialist Nicholas Patrick and fellow astronaut Robert Behnken (out of frame), carry out final steps to open the Cupola's seven windows.
Unicorns and roses are usually the stuff of fairy tales, but a new cosmic image taken by NASA's Wide-field Infrared Explorer (WISE) shows the Rosette Nebula located within the constellation Monoceros, or the Unicorn.
This flower-shaped nebula, also known by the less romantic name NGC 2237, is a huge star-forming cloud of dust and gas in our Milky Way galaxy. Estimates of the nebula's distance vary from 4,500 to 5,000 light-years away.
At the center of the flower is a cluster of young stars called NGC 2244. The most massive stars produce huge amounts of ultraviolet radiation, and blow strong winds that erode away the nearby gas and dust, creating a large, central hole. The radiation also strips electrons from the surrounding hydrogen gas, ionizing it and creating what astronomers call an HII region.
Although the Rosette Nebula is too faint to see with the naked eye, NGC 2244 is beloved by amateur astronomers because it is visible through a small telescope or good pair of binoculars. The English astronomer John Flamsteed discovered the star cluster NGC 2244 with a telescope around 1690, but the nebula itself was not identified until John Herschel (son of William Herschel, discoverer of infrared light) observed it almost 150 years later.
The streak seen at lower left is the trail of a satellite, captured as WISE snapped the multiple frames that make up this view.
This image is a four-color composite created by all four of WISE's infrared detectors. Color is representational: blue and cyan represent infrared light at wavelengths of 3.4 and 4.6 microns, which is dominated by light from stars. Green and red represent light at 12 and 22 microns, which is mostly light from warm dust.
NASA's Kepler spacecraft has discovered the first confirmed planetary system with more than one planet crossing in front of, or transiting, the same star.
The transit signatures of two distinct Saturn-sized planets were seen in the data for a Sun-like star designated "Kepler-9." The planets were named Kepler-9b and 9c. The discovery incorporates seven months of observations of more than 156,000 stars as part of an ongoing search for Earth-sized planets outside our solar system. The findings will be published in Thursday's issue of the journal Science.
Kepler's ultra-precise camera measures tiny decreases in the stars' brightness that occur when a planet transits them. The size of the planet can be derived from these temporary dips.
The distance of the planet from the star can be calculated by measuring the time between successive dips as the planet orbits the star. Small variations in the regularity of these dips can be used to determine the masses of planets and detect other non-transiting planets in the system.
In June, mission scientists submitted findings for peer review that identified more than 700 planet candidates in the first 43 days of Kepler data. The data included five additional candidate systems that appear to exhibit more than one transiting planet. The Kepler team recently identified a sixth target exhibiting multiple transits and accumulated enough follow-up data to confirm this multi-planet system.
"Kepler's high quality data and round-the-clock coverage of transiting objects enable a whole host of unique measurements to be made of the parent stars and their planetary systems," said Doug Hudgins, the Kepler program scientist at NASA Headquarters in Washington DC.
Scientists refined the estimates of the masses of the planets using observations from the W.M. Keck Observatory in Hawaii. The observations show Kepler-9b is the larger of the two planets, and both have masses similar to but less than Saturn. Kepler-9b lies closest to the star with an orbit of about 19 days, while Kepler-9c has an orbit of about 38 days. By observing several transits by each planet over the seven months of data, the time between successive transits could be analyzed.
"This discovery is the first clear detection of significant changes in the intervals from one planetary transit to the next, what we call transit timing variations," said Matthew Holman, a Kepler mission scientist from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts. "This is evidence of the gravitational interaction between the two planets as seen by the Kepler spacecraft."
In addition to the two confirmed giant planets, Kepler scientists also have identified what appears to be a third, much smaller transit signature in the observations of Kepler-9. That signature is consistent with the transits of a super-Earth-sized planet about 1.5 times the radius of Earth in a scorching, near-sun 1.6 day-orbit. Additional observations are required to determine whether this signal is indeed a planet or an astronomical phenomenon that mimics the appearance of a transit.
The giant, 70-meter-wide antenna at NASA's Deep Space Network complex in Goldstone, California, tracks a spacecraft on November 17, 2009. This antenna, officially known as Deep Space Station 14, is also nicknamed the "Mars antenna." Its name comes from its first task: to track the Mariner 4 spacecraft after its historic flyby of Mars in 1966.
Resembling the brush strokes of French Impressionist Claude Monet, electric blue-colored plankton blooms swirl in the North Atlantic Ocean off Ireland in this Envisat image. Plankton, the most abundant type of life found in the ocean, are microscopic marine plants that drift on or near the surface of the sea.
While individually microscopic, the chlorophyll they use for photosynthesis collectively tints the surrounding ocean waters, providing a means of detecting these tiny organisms from space with dedicated 'ocean color' sensors, like Envisat's Medium Resolution Imaging Spectrometer (MERIS), which acquired this image on 23 May 2010 at a resolution of 300 m.
This animation shows an artist’s impression of the remarkable planetary system around the Sun-like star HD 10180. Observations with the HARPS spectrograph, attached to ESO’s 3.6-meter telescope at La Silla, Chile, have revealed the definite presence of five planets and evidence for two more in orbit around this star. This system is similar to the Solar System in terms of number of planets and the presence of a regular pattern in the sizes of the orbits. If confirmed the closest planet detected would be the lightest yet known outside the Solar System, with a mass that could be as small as only 1.4 times that of the Earth.
Here we initially see the HD 10180 planetary system in its entirety with the planets labeled. As we close in on star we pass very close to the third planet in the system, the Neptune-sized world HD 10180d, and see the crescent of the second planet in the distance (HD 10180c).
This artist's concept illustrates an imminent planetary collision around a pair of double stars. NASA's Spitzer Space Telescope found evidence that such collisions could be common around a certain type of tight double, or binary, star system, referred to as RS Canum Venaticorums or RS CVns for short. The stars are similar to the Sun in age and mass, but they orbit tightly around each other. With time, they are thought to get closer and closer, until their gravitational influences change, throwing the orbits of planetary bodies circling around them out of whack.
Astronomers say that these types of systems could theoretically host habitable planets, or planets that orbit at the right distance from the star pairs to have temperatures that allow liquid water to exist. If so, then these worlds might not be so lucky. They might ultimately be destroyed in collisions like the impending one illustrated here, in which the larger body has begun to crack under the tidal stresses caused by the gravity of the approaching smaller one.
Spitzer's infrared vision spotted dusty evidence for such collisions around three tight star pairs. In this artist concept's, dust from ongoing planetary collisions is shown circling the stellar duo in a giant disk.
False-color composite view of Venus's southern hemisphere in the infrared (red: VIRTIS, 5 μm) and ultraviolet (purple: VMC, 0.365 μm). Brightness in the VIRTIS data tracks the cloud top temperature. The VMC UV data reveals the distribution of the unknown UV absorber at the cloud tops.
The oval feature in the polar region is the eye of the south polar vortex - a dynamical structure about 2000 km in size which is ~30 K warmer than its surroundings. The vortex eye is displaced from the south pole by about 1000 km, has an irregular and strongly variable shape, and rotates around the pole in ~2.5 days. The atmosphere rotates counter-clockwise in this view.
A dramatic new Chandra image of the nearby galaxy Centaurus A provides one of the best views to date of the effects of an active supermassive black hole. Opposing jets of high-energy particles can be seen extending to the outer reaches of the galaxy, and numerous smaller black holes in binary star systems are also visible.
The image was made from an ultra-deep look at the galaxy Centaurus A, equivalent to more than seven days of continuous observations. Centaurus A is the nearest galaxy to Earth that contains a supermassive black hole actively powering a jet.
A prominent X-ray jet extending for 13,000 light years points to the upper left in the image, with a shorter "counterjet" aimed in the opposite direction. Astronomers think that such jets are important vehicles for transporting energy from the black hole to the much larger dimensions of a galaxy, and affecting the rate at which stars form there.
High-energy electrons spiraling around magnetic field lines produce the X-ray emission from the jet and counterjet. This emission quickly saps the energy from the electrons, so they must be continually reaccelerated or the X-rays will fade out. Knot-like features in the jets detected in the Chandra image show where the acceleration of particles to high energies is currently occurring, and provides important clues to understanding the process that accelerates the electrons to near-light speeds.
The inner part of the X-ray jet close to the black hole is dominated by these knots of X-ray emission, which probably come from shock waves -- akin to sonic booms -- caused by the jet. Farther from the black hole there is more diffuse X-ray emission in the jet. The cause of particle acceleration in this part of the jet is unknown.
Hundreds of point-like sources are also seen in the Chandra image. Many of these are X-ray binaries that contain a stellar-mass black hole and a companion star in orbit around one another. Determining the population and properties of these black holes should help scientists better understand the evolution of massive stars and the formation of black holes.
Another surprise was the detection of two particularly bright X-ray binaries. These sources may contain stellar mass black holes that are unusually massive, and this Chandra observation might have caught them gobbling up material at a high rate.
In this image, low-energy X-rays are colored red, intermediate-energy X-rays are green, and the highest-energy X-rays detected by Chandra are blue. The dark green and blue bands running almost perpendicular to the jet are dust lanes that absorb X-rays. This dust lane was created when Centaurus A merged with another galaxy perhaps 100 million years ago.
This image shows the eruption of a galactic "super-volcano" in the massive galaxy M87, as witnessed by NASA's Chandra X-ray Observatory and NSF's Very Large Array (VLA). At a distance of about 50 million light years, M87 is relatively close to Earth and lies at the center of the Virgo cluster, which contains thousands of galaxies.
The cluster surrounding M87 is filled with hot gas glowing in X-ray light (shown in blue) that is detected by Chandra. As this gas cools, it can fall toward the galaxy's center where it should continue to cool even faster and form new stars.
However, radio observations with the VLA (red-orange) suggest that in M87 jets of very energetic particles produced by the black hole interrupt this process. These jets lift up the relatively cool gas near the center of the galaxy and produce shock waves in the galaxy's atmosphere because of their supersonic speed.
The interaction of this cosmic "eruption" with the galaxy's environment is very similar to that of the Eyjafjallajokull volcano in Iceland that occurred in 2010. With Eyjafjallajokull, pockets of hot gas blasted through the surface of the lava, generating shock waves that can be seen passing through the grey smoke of the volcano. This hot gas then rises up in the atmosphere, dragging the dark ash with it. This process can be seen in a movie of the Eyjafjallajokull volcano where the shock waves propagating in the smoke are followed by the rise of dark ash clouds into the atmosphere.
Video: Omar Ragnarsson
In the analogy with Eyjafjallajokull, the energetic particles produced in the vicinity of the black hole rise through the X-ray emitting atmosphere of the cluster, lifting up the coolest gas near the center of M87 in their wake. This is similar to the hot volcanic gases that drag up the clouds of dark ash. And just like the volcano here on Earth, shock waves can be seen when the black hole pumps energetic particles into the cluster gas. The energetic particles, coolest gas and shock waves are shown in a labeled version.
This image from NASA's Hubble Space Telescope shows the inner region of Abell 1689, an immense cluster of galaxies located 2.2 billion light-years away. The cluster's gravitational field is warping light from background galaxies, causing them to appear as arcs. The effect is similar to what happens when you look into a fun house mirror.
Dark matter in the cluster, which represents about 80 percent of its mass, is mapped by plotting these arcs. Dark matter cannot be photographed, but its distribution is shown in the blue overlay. The dark matter distribution is then used to better understand the nature of dark energy, a pressure that is accelerating the expansion of the universe.
The natural-color photo was taken with Hubble's Advanced Camera for Surveys.
Astronomers have found that stars are forming more rapidly in the center of a distant galaxy cluster than at its edges, which is completely reversed from galaxy clusters seen in the local universe. This cluster, designated CLG J02182-05102, is highlighted in the circle above.
The image combines infrared light from NASA's Spitzer Space Telescope with visible light from Japan's Subaru telescope atop Mauna Kea, Hawaii. This sensitive exposure captures galaxies that are relatively local along side some that date back almost 10 billion years, soon after the Big Bang. The most distant galaxies stand out clearly in the infrared, rendered here in green and red.
What is noteworthy is how many of these galaxies are particularly bright at the longest infrared wavelengths, appearing red in this image. This glow indicates these ancient galaxies are still actively forming stars, even near the core of the cluster. In our local portion of the universe, the cores of galaxy clusters are known to be galactic graveyards full of massive elliptical galaxies composed of old stars.
The group's discovery holds potentially compelling implications that could ultimately reveal more about how such massive galaxies form. Now that they have pinpointed the epoch when galaxy clusters are making the last of their stars, astronomers can focus on understanding why massive assemblies of galaxies transition from very active to passive. The galaxies here may represent a missing link between the active galaxies and the quiescent behemoths that live in the local universe.
Infrared light from Spitzer at wavelengths of 4.5 and 24 microns is rendered in green and red, respectively. Subaru observations of visible light at a wavelength of 0.7 microns are rendered in blue. These data are part of the Spitzer Wide-area InfraRed Extragalactic (SWIRE) survey.
This artist’s impression shows the Magnetar in the very rich and young star cluster Westerlund 1. This remarkable cluster contains hundreds of very massive stars, some shining with a brilliance of almost one million suns. European astronomers have for the first time demonstrated that this magnetar — an unusual type of neutron star with an extremely strong magnetic field — was formed from a star with at least 40 times as much mass as the Sun. The result presents great challenges to current theories of how stars evolve, as a star as massive as this was expected to become a black hole, not a magnetar.
NASA's Wide-field Infrared Survey Explorer, or WISE, has captured a favorite observing target of amateur astronomers -- Omega Centauri. Also known as NGC 5139, this celestial cluster of stars can be found in the constellation Centaurus and can be seen by the naked eye to observers at low northern latitudes and in the southern hemisphere. Omega Centauri contains approximately 10 million stars and is about 16,000 light-years away. This image spans an area on the sky equivalent to a grid of about 3 by 2 full moons.
The ancient astronomer Ptolemy thought Omega Centauri was a star, and Edmond Halley identified it as a nebula in 1677. In the 1830s, John Herschel identified it as a globular star cluster orbiting our Milky Way galaxy. A globular cluster is a spherical group of stars that are bound together by gravity.
Omega Centauri has always been the black sheep of globular clusters, since it has several characteristics that mark it as different from the typical globular cluster. For example, Omega Centauri is ten times more massive than other globular clusters. It also includes stars of a variety of ages, whereas other globular clusters contain stars from only one generation.
Recent research based on observations using NASA's Hubble Space Telescope and the Gemini Observatory indicates that there is a black hole at its center. This suggests that Omega Centauri may actually be a dwarf galaxy that has been stripped of its outer stars and not a globular cluster after all.
All four infrared detectors aboard WISE were used to create this mosaic image of Omega Centauri. The colors blue and cyan represent light emitted from stars at wavelengths of 3.4 and 4.6 microns. The green halo surrounding the center represents light at 12 microns, emitted by warm dust.
Thinking about locations on the Moon where humans should be exploring is nothing new. In the late 1950s, at the dawn of the Space Age (when Project Mercury was still getting off the ground), the United States Army proposed to establish a large lunar base to use for a variety of science, engineering, and military tasks. Despite the paucity of data about the lunar surface at that point in history, the Army team that proposed Project Horizon suggested several notional sites for this lunar outpost based on what was known at the time. One of these sites was located near this region in Sinus Aestuum, located southeast of Eratosthenes Crater just beyond the southern rim of the of the great Imbrium basin.
We know more about the Moon now than we did when this location was proposed over five decades ago. Knowing what we do now, it turns out that this would have been a fantastic location for an early lunar outpost. As you can see in the image above, this mare surface is relatively smooth, the near-equatorial location would have made for a dynamically favorable landing target, and the nearside location would enable continuous real-time communications with Earth. The location would have permitted sampling (and age-dating) the rays of Copernicus and direct exploration of Eratosthenes Crater, the foundations for the lunar stratigraphic time scale. This location is centrally located between several targets now known to have high scientific and exploration interest, including the aforementioned Eratosthenes Crater, Copernicus Crater, the rich ores of the Rima Bode regional dark mantling deposit, the Sinus Aestuum regional dark mantling deposit, and the southern rim of the Imbrium Basin, although an extended surface traverse would have been required to access those locations from this site. Future robotic and human lunar sortie missions will provide important new scientific insights into the lunar surface, but long-duration human lunar outposts will provide even more valuable benefits, including the flexibility to make exploration forays that last longer (or even repeat visits) to key scientific locations, as well as providing more infrastructure to leverage existing lunar resources.
A long-exposure Hubble Space Telescope image shows a majestic face-on spiral galaxy located deep within the Coma Cluster of galaxies, which lies 320 million light-years away in the northern constellation Coma Berenices.
The galaxy, known as NGC 4911, contains rich lanes of dust and gas near its center. These are silhouetted against glowing newborn star clusters and iridescent pink clouds of hydrogen, the existence of which indicates ongoing star formation. Hubble has also captured the outer spiral arms of NGC 4911, along with thousands of other galaxies of varying sizes. The high resolution of Hubble's cameras, paired with considerably long exposures, made it possible to observe these faint details.
NGC 4911 and other spirals near the center of the cluster are being transformed by the gravitational tug of their neighbors. In the case of NGC 4911, wispy arcs of the galaxy's outer spiral arms are being pulled and distorted by forces from a companion galaxy (NGC 4911A), to the upper right. The resultant stripped material will eventually be dispersed throughout the core of the Coma Cluster, where it will fuel the intergalactic populations of stars and star clusters.
The Coma Cluster is home to almost 1,000 galaxies, making it one of the densest collections of galaxies in the nearby universe. It continues to transform galaxies at the present epoch, due to the interactions of close-proximity galaxy systems within the dense cluster. Vigorous star formation is triggered in such collisions.
Galaxies in this cluster are so densely packed that they undergo frequent interactions and collisions. When galaxies of nearly equal masses merge, they form elliptical galaxies. Merging is more likely to occur in the center of the cluster where the density of galaxies is higher, giving rise to more elliptical galaxies.
This natural-color Hubble image, which combines data obtained in 2006, 2007, and 2009 from the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys, required 28 hours of exposure time.
Curling around itself like a question mark, the unusual looking galaxy NGC 4696 itself begs many questions. Why is it such a strange shape? What are the odd, capillary-like filaments that stretch out of it? And what is the role of a large black hole in explaining its decidedly odd appearance?
This picture, taken by Hubble's Advanced Camera for Surveys, is not just a beautiful snapshot of NGC 4696, the largest galaxy in the Centaurus Cluster (galaxy cluster Abell 3526). It is also an illustration of the rich variety of objects that astronomers can see with the NASA/ESA Hubble Space Telescope.
NGC 4696 is an elliptical galaxy with a difference. Lacking the complex structure and active star formation of their spiral brethren, elliptical galaxies are usually little more than shapeless collections of aging stars.
Most likely formed by collisions between spiral galaxies, elliptical galaxies experience a brief burst of star formation triggered as the interstellar dust and gas crash into each other, but which quickly leaves the young elliptical galaxies exhausted. With no more gas to form new stars from, the galaxies gradually grow older and fainter.
But NGC 4696 is more interesting than most elliptical galaxies.
The huge dust lane, around 30,000 light-years across, that sweeps across the face of the galaxy is one way in which it looks different from most other elliptical galaxies. Viewed at certain wavelengths, strange thin filaments of ionized hydrogen are visible within it. In this picture, these structures are visible as a subtle marbling effect across the galaxy's bright center.
Looking at NGC 4696 in the optical and near-infrared wavelengths seen by Hubble gives a beautiful and dramatic view of the galaxy. But in fact, much of its inner turmoil is still hidden from view in this picture. At the heart of the galaxy, a supermassive black hole is blowing out jets of matter at nearly the speed of light. When looked at in X-ray wavelengths (see related links for a view of NGC 4696 by NASA's Chandra X-ray Observatory), huge voids within the galaxy become visible, telltale signs of these jets' enormous power.
The picture was created from images taken using the NASA/ESA Hubble Space Telescope's Advanced Camera for Surveys. A total of 5,440 seconds of exposure through a blue filter (F435W, shown in blue) were combined with 2,320 seconds of exposure through a near-infrared filter (F814W, shown in red). The field of view is 3.2 by 1.5 arcminutes.
This VISTA image shows the spectacular 30 Doradus star-forming region, also called the Tarantula Nebula. At its core is a large cluster of stars known as R 136, in which some of the most massive stars known are located. This infrared image, made with ESO’s VISTA survey telescope, is from the VISTA Magellanic Cloud Survey. The project will scan a vast area — 184 square degrees of the sky (corresponding to almost one thousand times the apparent area of the full Moon), including our nearby neighboring galaxies, the Large and Small Magellanic Clouds. The end result will be a detailed study of the star formation history and three-dimensional geometry of the Magellanic system.
This image was created from images taken through Y, J and Ks filters in the near-infrared part of the spectrum (colored blue, green and red respectively). The exposure times were 40, 47 and 81 minutes per filter respectively. The image covers a region of sky about 52 by 70 arcminutes.
Astronomers have found unexpected rings and arcs of ultraviolet light around a selection of galaxies, four of which are shown here as viewed by NASA's and the European Space Agency's Hubble Space Telescope.
Observations from NASA's Galaxy Evolution Explorer (GALEX) picked out 30 elliptical and lens-shaped "early-type" galaxies with puzzlingly strong ultraviolet emissions but no signs of visible star formation. Early-type galaxies, so the scientists' thinking goes, have already made their stars and now lack the cold gas necessary to build new ones.
Hubble images captured the great, shining rings of ultraviolet light, with some ripples stretching 250,000 light-years.
In these Hubble images, ultraviolet light has been rendered in blue, while green and red light from the galaxies is shown in their natural colors.
The study detailing the findings appeared in the April 21 issue of the Astrophysical Journal.
This image shows a map of the Galactic Bulge region, reconstructed from data collected over seven years, from 2003 to 2010, with IBIS/ISGRI on board INTEGRAL, and covering the 17-60 keV energy band. The overlaid green contours are isophotes of the 4.9-micron surface brightness of the Galaxy as seen by COBE/DIRBE, revealing the bulge/disc structure of the inner Galaxy. The near-infrared brightness of the Galaxy traces also the hard X-ray Galactic Ridge emission.
This image captured by NASA's Wide-field Infrared Survey Explorer (WISE) highlights the Small Magellanic Cloud. Also known as NGC 292, the Small Magellanic Cloud is a small galaxy about 200,000 light-years away.
The Small Magellanic Cloud is named after the Portuguese explorer Fernando de Magellan who observed it on his voyage around the world in 1519. Since it is visible to the naked eye in dark-sky conditions, it is likely that people in the southern hemisphere observed the galaxy long before Magellan recorded it.
Located in the constellation Tucana, the Small Magellanic Cloud looks like a wispy cloud that circles the south celestial pole. Nearby, but not visible in this image, is the Large Magellanic Cloud, a sister galaxy to the Small Magellanic Cloud. Astronomers originally thought that both galaxies were orbiting our Milky Way galaxy. But recent research suggests that they might be moving too fast to be bound by the Milky Way's gravity and are passing by for the first time.
This WISE image illustrates why the SMC is considered an irregular galaxy. Galaxies are classified according to their shape, such as spiral or elliptical. Irregular galaxies don't fit into any of these categories -- they are unique in shape.
The two streaks seen in the upper half of the image are satellites orbiting Earth, which happened to pass in front of the Small Magellanic Cloud when WISE captured this view.
This mosaic image was made from all four infrared detectors aboard WISE. The color in this image represents different wavelengths of infrared light. Blue and cyan represent light at wavelengths of 3.4 and 4.6 microns mostly emitted from stars. Green and red represent light at 12 and 22 microns, which is mostly light from warm dust.
Bright spokes can be seen on Saturn's B-ring just in front of the shadow cast on the rings on the night side of the planet in this Cassini spacecraft image.
The spokes are on the left of the image. See PIA12605 to learn more. Saturn's moon Tethys (1,062 kilometers, or 660 miles across) can be seen in the upper right of the image. The moon Enceladus (504 kilometers, or 313 miles across) is visible in the lower right. Both moons are overexposed.
This view looks toward the northern, sunlit side of the rings from about 8 degrees above the ringplane.
The image was taken in visible green light with the Cassini spacecraft wide-angle camera on May 30, 2010. The view was obtained at a distance of approximately 1.9 million kilometers (1.2 million miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 104 degrees. Image scale is 110 kilometers (68 miles) per pixel.
For the first time, astronomers have been able to directly follow the motion of an exoplanet as it moves to the other side of its host star. The planet has the smallest orbit so far of all directly imaged exoplanets, lying as close to its host star as Saturn is to the Sun.
The team of astronomers used the NAOS-CONICA instrument (or NACO), mounted on one of the 8.2-meter Unit Telescopes of ESO's Very Large Telescope (VLT), to study the immediate surroundings of Beta Pictoris in 2003, 2008 and 2009. In 2003 a faint source inside the disc was seen, but it was not possible to exclude the remote possibility that it was a background star. In new images taken in 2008 and spring 2009 the source had disappeared! The most recent observations, taken during autumn 2009, revealed the object on the other side of the disc after having been hidden either behind or in front of the star. This confirmed that the source indeed was an exoplanet and that it was orbiting its host star. It also provided insights into the size of its orbit around the star.
The above composite shows the reflected light on the dust disc in the outer part, as observed in 1996 with the ADONIS instrument on ESO's 3.6-meter telescope. In the central part, the observations of the planet obtained in 2003 and autumn 2009 with NACO are shown. The possible orbit of the planet is also indicated, albeit with the inclination angle exaggerated.
