The "ring of fire" seen by satellite cameras around the polar caps (picture below) is probably created by electrons leaking from the tail's plasma sheet, whose magnetic field lines form a somewhat imperfect trap. ... One possible explanation involves the close association between auroral arcs and electric currents which flow along field lines between the ionosphere and distant space ( Birkeland currents ). ... That produces an extra resistance to the flow of current. ...

... Aurora from Space . ... Magnetic Storms . ... The "ring of fire" seen by satellite cameras around the polar caps (picture below) is probably created by electrons leaking from the tail's plasma sheet, whose magnetic field lines form a somewhat imperfect trap. ... One possible explanation involves the close association between auroral arcs and electric currents which flow along field lines between the ionosphere and distant space ( Birkeland currents ). ... Why no aurora at the magnetic poles? ...

Databases (NSDC) of the Natural Planetary Satellites. ... NSDC: Database of astrometric observations of Natural Planetary Satellites . ... They are thoroughly looking for observations in different sources, creating their owndatabases which are then mostly inaccessible to other researchers. ... In the file "content" with explications, the reference is given to the data source as well as the bibliographic reference. ... Data sources. ... Why a specific bibliographic database for Natural satellites? ...

. The XMM-Newton website has moved to the following location: . http://www.cosmos.esa.int/web/xmm-newton

... 8, ``Celestial Mechanics'', 2002 Earth penumbra effects on AES motion taking into account the refraction and the extinction of the light in the atmosphere A. M. Fominov Institute of Applied Astronomy, St. Petersburg, Russia The perturbing acceleration F of the Artificial Earth Satellite (AES) due to the solar ... In step 1, the table of the shadow function values with the angle distances d between the solar disk and the earth disk edge may be calculated. ...

... Observatory . ... Science . ... Science Users Information > Data Handling and Products > Data Reduction FAQ > How can I improve the flux calibration of my spectra? ... Observing Facilities . ... Observing with ESO Telescopes . ... Data Pipelines and Calibrations . ... Science Data Products Forum . ... ESO Data . ... Also to ensure the best possible flux calibration, your science observations should have 5" slits observations, i.e. same slits than for the specphot standard star observations. ...

HUBBLE SPACE TELESCOPE DAILY REPORT #954 PERIOD COVERED: 0800 EST Daily Status Report as of 231/1200Z. 1.0 ACTIVITIES SCHEDULED AND ACCOMPLISHED: 1.1 Complete PC 5020 (Separate Light Curves of Pluto and Charon - Split of 3848) The Planetary Camera was used to make two photometry observations of the planet Pluto and its moon Charon. ... 1.6 Complete FGS 5062 (Scale Cycle 2 Calibration - Fixed) Fine Guidance Sensor #3 was used to calibrate the scale in the central region using standard star HD16620. ...

... HVAC flow rate reduction improves sensitivity Seismic up-conversion experiments S4 H1-H2 coincident events from site activity PEM injections Electronics rack diagnostic magnetometer Crab protection 1 Gravitational wave sensitivity improves when HVAC off Blue: All site turbines and chiller pad equipment off; Red: normal 2 Half-normal flow rate about as good as fans off DARM Black: off; Blue: Ѕ flow ; Red: full flow seismometer 3 ... Labs at 50% D)Full LVEA flow with 3 fans. ...

... Bad Astronomy . ... Bitesize Astronomy . ... Bad Astro Store . ... Site Info . ... It is from from Voyager 1 and shows a whopping big impact crater dominating the profile of the moon. Note that Mimas is about 400 kilometers across (about 250 miles). ... The wall around the crater is 5 kilometers high, and that central peak rises 6 kilometers above the surface (many impact craters have a large central peak which is caused by a pressure rebound from the impact). ... 2008 Phil Plait. ...

... Binary orbits in the acceleration/period plane . Circular Orbits . ... We first present the equations for the period and acceleration of a pulsar in an eccentric binary system as a function of its position in the orbit. ... In Freire, Kramer & Lyne (2001) (from where most of this text and following equations are taken), we describe in more detail how circular binary orbits can be determined from the observed periods and accelerations of the pulsar. ... where is the orbital period of the binary. ...

In 2007-2008, the planet Uranus will reach one of its annual equinoxes for the first time since 1966. As a consequence, its five major satellites orbiting in the equatorial plane will undergo a season of mutual eclipses and occultations very similar to the one that Jupiter's Galilean satellites undergo every 6 years. ... Some of these events occur when Uranus is at conjunction, or the satellite is transiting or too close to the limb of the planet. ... Complete table of events . ...

ATNF Home . ... About ATNF overview . ... Australia Telescope Steering Committee . ... Australia Telescope User Committee . ... Murchison Radio-astronomy Observatory . ... Parkes radio telescope . Australia Telescope Compact Array . Mopra radio telescope . ... Information & tools for observers . ... Australia Telescope Online Archive (ATOA) . ... ATCA | ... Visiting Parkes radio telescope . ... Parkes radio telescope webcam . ... The Australia Telescope National Facility Colloquium . ...

University Satellites and . Space Science Education . ... It is necessary to select a topic interesting from scientific point of view and simple enough to allow students understand and participate in all stages of experiment from measurements via data analysis to physical inference. ... Solar modulation effects and physical characteristics and analysis of the major solar events are possible only by joining data from space-born and surface particle and radiation detectors. ...

... The SMS program is a critical endeavor to investigate whether the predictions of standard cold dark matter cosmology are consistent with the observed matter distribution in the Milky Way halo. It is the deepest, most extended search for optically elusive dwarf satellite galaxies and tidal streams to date, covering the entire Southern hemisphere. ... However only a few dwarf satellites have been found around the Milky Way to date - 22 dwarfs compared to 500-10,000 predicted by theory (Klypin et al. ...

... Basic Observables: Zero-differenced phase and code ionosphere-free combinations of global GNSS network stations, corrected by P1-C1 satellite code biases (cc2noncc), daily observations with 30 seconds sampling rate Sites coordinates : IGb08 reference frame coordinates and velocities Displacements: solid tides, ocean loading, pole tide loading (IERS 2010) Geometric model : Receivers antennas eccentricities, absolute receiver and ...

... Solar System . ... Pioneering Solar Sail: Artist?s impression of Nanosail-D after deployment above Earth?s atmosphere (image credit: NASA) . ... This is the basic idea behind solar sails, however the practical application of this theory hasnтАЩt always run a smooth course. ... Cosmos 1 was to be the first solar sail spacecraft, which would rely exclusively on solar pressure to control the crafts orbit. ... The solar sail had confirmed acceleration due to solar radiation by 9 July 2010. ...

For non-spherical isotropic particles, the classic variant of the RDG approximation does not include the anisotropy of the shape and hence does not give the correct Rayleigh limit, say, for small ellipsoids. ... We call this variant a modified RDG approximation (MRDG). ... First, the MRDG leads to the correct Rayleigh limit. ... The second approach to generalization of the RDG is connected with the use of the Born iterations for the scattering integral equation [ 95 , 124 , 132 , 264 ]. ...

Next: Input and Output Up: CCD Reductions Previous: Basic Reduction Steps . Before the actual processing can start, multiple calibration frames have to been combined into a master. The command that takes care of combining the calibration frames in the CCD package is COMBINE/CCD . ... Depending on the actual parameter settings, the command can take into account the exposure times in the combining process, and can adjust for a (variable) sky background. ... Combining Bias Frames . ...

AGP=Accelerated Graphics Port . ... 132 PIN EDGE CONNECTOR at the computer. ... Reserved* Ground . ... Ground . ... VCC 3.3 . ... Vddq 3.3 . ... AGP pinout at The Pin-Out directory . ...

Structure Formation : Bright side of the Universe Anatoly Klypin New Mexico State University Also: Stefan Gottloeber (Astrophysikalisches Institut Potsdam) Gustavo Yepes (UAM, Madrid) Cosmological ... -body+hydro simulations Codes: SPH + TREE AMR + shock capturing hydro Physical processes: Compton cooling/heating on CMB Radiative gas cooling Star formation with simple approximations Metal enrichment Energy/momentum feedback from young stars and SN Galaxies too concentrated. ...