New observations on the Galactic Center gas cloud "G2"
September 12, 2012
New observations on the gas cloud "G2" falling towards the Galactic Center confirm its highly elliptical orbit, but with updated orbital parameters. With the new data, the cloud is now expected to come even closer -- the updated pericenter distance is 2200 Schwarzschild radii -- to the super-massive black hole at the center of our galaxy. While its origin is still unclear, its apocenter is near the inner edge of the disk of young stars. This supports speculations that the cloud, which has a mass of only about three earth masses, originated as a wind of one of these stars.
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In the course of this year, more observations of the cloud are planned, of course, and not only in the infrared but campaigns have been started by many groups to observe this accretion event in the whole electromagnetic spectrum. A wiki page has been set up to collect all information on "G2".
More information:
top of page This composite image shows the positions of the gas cloud in 2002, 2007, and 2011 marked in colour. The cross indicates the position of the black hole in the galactic centre. Image: MPE |
Galactic Black Hole disrupts Gas CloudOver the next few years, astronomers will be able to observe first-hand how the super massive black hole at the centre of our Milky Way is being fed: an international team of astronomers led by the Max Planck Institute for Extraterrestrial Physics has found a gas cloud that is falling towards the black hole in the galactic centre. While some distortion due to the huge gravitational pull of the black hole can already be seen, the gas cloud will be completely disrupted and ultimately swallowed by the black hole, resulting in largely increased X-ray emission. The observations and analysis are described in a Nature paper, published online on 14 December 2011. For more information see  MPE Press Release. |
 This illustration shows an Ultra-Luminous InfraRed Galaxy (ULIRG) that exhibits massive outflows of molecular gas. Image: MPE |
Caught in the act: Herschel detects gigantic storms sweeping entire galaxies cleanWith observations from the PACS instrument on board the ESA Herschel space observatory, an international team of scientists led by the Max Planck Institute for Extraterrestrial Physics have found gigantic storms of molecular gas gusting in the centres of many galaxies. Some of these massive outflows reach velocities of more than 1000 kilometres per second, i.e. thousands of times faster than in terrestrial hurricanes. The observations show that the more active galaxies contain stronger winds, which can blow away the entire gas reservoir in a galaxy, thereby inhibiting both further star formation and the growth of the central black hole. This finding is the first conclusive evidence for the importance of galactic winds in the evolution of galaxies. For more information see MPE Press Release. |
 This image of the GOODS-S field with the Herschel PACS instrument demonstrates that the weak cosmic infrared radiation is produced mainly by individual galaxies. Image: MPE |
Herschel Space Telescope: Successful first year for German researchersOne year after the launch of ESA's Herschel space telescope, German scientists have reason to celebrate: The instruments' performance and first results have exceeded all expectations. Initial observations with the largest telescope currently in space, which was designed primarily to study the coldest matter in our Universe, have led to new insights into the formation of stars, the properties of dust in distant galaxies and the presence of molecules in interstellar clouds. For more information see MPE Press Release. |
 Star forming region in the Milky Way |
Making the invisible visibleThe Large Binocular Telescope (LBT) partners in Germany, the U.S.A. and Italy are pleased to announce that the first of two new innovative near-infrared cameras/spectrographs for the LBT is now available to astronomers for scientific observations at the telescope on Mt. Graham in south-eastern Arizona. After more than a decade of design, manufacturing and testing, the new instrument, dubbed LUCI 1, provides a powerful tool to gain spectacular insights into the universe, from the Milky Way up to extremely distant galaxies. LUCI 1 has been built by a consortium of German institutes and will be followed by an identical twin instrument that will be delivered to the telescope in early 2011. For more information see MPE Press Release. |
 Herschel image of the Rosette nebula Image: ESA/PACS & SPIRE Consortium/HOBYS Key Programme Consortia |
Where stars are born...Herschel's latest image reveals the formation of previously unseen large stars, each one up to ten times the mass of our Sun. These are the stars that will influence where and how the next generation of stars are formed. The Rosette Nebula resides some 5,000 light years from Earth and is associated with a larger cloud that contains enough dust and gas to make the equivalent of 10,000 Sun-like stars. The Herschel image shows half of the nebula and most of the Rosette cloud. The massive stars powering the nebula lie to the right of the image but are invisible at these wavelengths. Each colour represents a different temperature of dust, from -263°C (only 10ºC above absolute zero) in the red emission to -233ºC in the blue. |
ESA Press Release  IRAM  Galaxy EGS 1305123 Copyright: MPE/IRAM
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Young galaxies gorge on gasScientists find explanation for higher star formation rate in young galaxiesStars form from giant gas clouds in galaxies - the star formation rate however has changed over cosmic timescales. In the young universe many more stars were born. Scientists from the Max Planck Institute for extraterrestrial Physics, together with an international team of astronomers have found a plausible explanation: a few billion years after the Big Bang, normal star forming galaxies contained five to ten times more cold gas than today, providing more "food" to fuel the star formation process. |
 IRAS 4B in NGC 1333 in the radio |
Pin-pointing water in spaceFor the first time, scientists succeeded in localising large amounts of water in a disk around a young starWater is regarded as a key ingredient for life - and water exists plenty in the universe. Now scientists have found the precious element in a disk around a young star, similar to our Sun. This disk, supposedly the birth place for future planets, contains a hundred times more than all oceans on Earth. The astronomical observations obtained with the IRAM interferometer appear very promising to solve the mystery around the origin of water in our solar system |
MPE Highlight and Press Release:
 Herschel-PACS images of the 'GOODS-N' field in the constellation of Ursa Major at far-infrared wavelengths of 100 and 160 µm. Image: MPE |
Herschel Space Telescope uncovers the sources of the Cosmic Infrared BackgroundA weak cosmic infrared radiation field that reaches Earth from all directions contains not yet deciphered messages about the evolution of galaxies. Using first observations with the PACS Instrument on board ESA's Herschel Space Telescope, scientists from the Max Planck Institute for Extraterrestrial Physics and other institutions have for the first time resolved more than half of this radiation into its constituting sources. Observations with Herschel open the road towards understanding the properties of these galaxies, and trace the dusty side of galaxy evolution. |
 Hα velocity fields |
SINS: Gas kinematics and star formation of 100 high redshift galaxies with SINFONIOur data resolve the emission line distributions and kinematics (primarily Hα) on scales of ~1-5 kpc. About 1/3 of the galaxies are rotation-dominated yet turbulent disks, 1/3 are more compact dispersion dominated objects, and 1/3 are clear mergers (illustrated with the Hα velocity fields of 30 of the 103 sources below). The data imply comparable current and past-averaged SFRs, high gas mass fractions of ~30% and baryonic mass fractions of ~60%-80% within ~10kpc. The high z disks are more turbulent and gas-rich than their z~0 counterparts, often showing luminous massive (~107.5-109.5Mo) kpc-sized "clumps", as expected for Toomre-unstable gas-rich disks. A picture emerges in which the gas reservoirs of the galaxies are constantly replenished, fueling intense star formation over a substantial part of their stellar lifetimes and ~10 dynamical timescales. This suggests steady gas accretion via cold flows or rapid series of minor mergers (as opposed to violent dissipative major mergers) is at play, heating the disks without destroying the highly ordered gas motions. |
 Part of the milkyway in IR Image: MPE ( high resolution) |
Herschel views deep-space pearls on a cosmic string Europe's new space observatory Herschel has delivered marvellous vistas of cold gas clouds lying near the plane of the Milky Way.
Further MPE/PACS milestones:
Contact: |
 Far-infrared colour image of the "Whirlpool Galaxy" M51. |
Herschel's first glimpse of the Universe The PACS team at MPE is all excited: After the successful opening of the satellite's cryostat lid on Sunday, June 14, the instruments on board had their first view of the Universe. Against all odds, the Photodetector Array Camera and Spectrometer (PACS) was immediately able to capture some images, which far exceeded all our expectations. They already demonstrated - at this early phase of the mission - the superiority of Herschel, the largest infrared space telescope. [
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 Gas Streamers in NGC1068 |
Gas Streamers in NGC 1068Although a prototypical Seyfert 2, NGC 1068 is in fact rather unusual. The H2 emission in the central 250pc originates in an expanding off-centre shell with particularly bright and massive clumps around the north east side. Filaments of gas extend from the ring at a radius of about 30pc to the AGN on both sides. Modelling the morphology and kinematics of the filaments has shown that the only way to simultaneously account for both constraints is if they trace gas that is falling almost directly in towards the AGN. These models indicate that the infall timescale is about 1.3Myr. One of the filaments lies across the front of the AGN, suggesting that inelastic collisions may allow the gas to settle on scales of a few parsecs. |
The central 25 arcseconds of our Milky Way. |
Unprecedented 16-Year Long Study Tracks Stars Orbiting Milky Way Black Hole In a 16-year long study, using several of ESO's flagship telescopes, a team of German astronomers has produced the most detailed view ever of the surroundings of the monster lurking at our Galaxy's heart — a supermassive black hole. The research has unravelled the hidden secrets of this tumultuous region by mapping the orbits of almost 30 stars, a five-fold increase over previous studies. One of the stars has now completed a full orbit around the black hole.
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