... With enough velocity, a spacecraft can break loose from the Earth's gravity and enter an orbit around the Sun, like that of a planet. If it then orbits the Sun with the same period as the Earth--one year--it may keep a fixed position relative to Earth. ... If the distance is just right--about 4 times the distance to the Moon or 1/100 the distance to the Sun--the spacecraft, too, will need just one year to go around the Sun, and will keep its position between the Sun and the Earth. ...

... With enough velocity, a spacecraft can break loose from the Earth's gravity and enter an orbit around the Sun, like that of a planet. If it then orbits the Sun with the same period as the Earth--one year--it may keep a fixed position relative to Earth. ... If the distance is just right--about 4 times the distance to the Moon or 1/100 the distance to the Sun--the spacecraft, too, will need just one year to go around the Sun, and will keep its position between the Sun and the Earth. ...

... Current APO Weather . ... Search Site . ... Information for New Users . ... Technical Staff pages . Night Logs and Mailing Lists (maintained by APO) . ... Technical Documents and Database Search . ... Observer's Documentation and Procedures . ... Problem Reporting and APO Technical Documents Database Search . ... APO Drawing/Document Management Procedures . ... APO Technical Documents Database Search . Home Astrophysical Research Consortium . ... Mail Lists (maintained by APO) . ...

... Our restless globe and its companion. ... A Look at the Motions of the Earth in Space and How They Are Changing . ... Earth's rotation as viewed from above the north and south geographic poles. ... The Earth revolves around the Sun-also counterclockwise viewed from above the North Pole, clockwise viewed from the South Pole-to give us our years (see Figure 2 ). The plane of the Earth's orbit is called the ecliptic (where eclipses happen). ... Earth's orbit as viewed from the north ecliptic pole. ...

... These two images of the Jovian moon Thebe were taken by Galileo's solid state imaging system in November 1996 and June 1997, respectively. ... Thebe, whose longest dimension is approximately 116 kilometers (72 miles) across, is tidally locked so that the same side of the satellite always points towards Jupiter, similar to how the near side of our own Moon always points toward Earth. ... The image on the right emphasizes the side of Thebe that faces away from Jupiter (the "anti-Jupiter" side). ...

... connection points . ... The point P3 is the connection between the horizontal and vertical actuators and is the axis of rotation for the tail gunner motion. processing: survey/020204/reduc We can compute P3,P5 (the moveable points) in dome centerline coordinates if we have the actuator distances and we know the positions of the above connection points in dome centerline coordinates for a given position of the tertiary (say the nominal focus position).(see actuator distances to dome centerline ). ...

GRANAT is the Russian x-ray sattelite launched to the high apogee orbit (200,000 km) and operated almost for 10 years (1989 -1999) , carrying out four major instruments: French SIGMA coded-mask hard x-ray telescope (30-1000 keV), Soviet ART-P coded-mask telescope (2??-60?? keV), all-sky monitor WATCH (6-150 keV), and a gamma-burst detector PHEBUS . ... Since September 1994, GRANAT is in the survey mode. ... Explore pages devoted to individual GRANAT instruments (including main scientific results): . ...

... Abstract Find the nearest point on a line to a specified point, and find the distance between the two points. Required_Reading None. Brief_I/O Variable I/O Description -------- --- -------------------------------------------------- linpt, lindir I Point on a line and the line's direction vector. point I A second point. pnear O Nearest point on the line to point. dist O Distance between point and pnear. ... Index_Entries distance between point and line nearest point on line to point . ...

... 11.04.2012 . ... Credit Copyright: Michael Kunze Explanation: Why don't those stars move? Stars in the sky will typically appear to rise and set as the Earth turns. ... Called geostationary satellites , they don't fall down because they do orbit the Earth -- they just orbit at exactly the same speed that the Earth rotates . ... The satellites also all appear on a single line -- actually the projection of the Earth's equator onto the sky. ... April . ... April 2012 . ... 2011 2012 . ...

WCSLIB љ 5.15 . ... sph.h File Reference . Go to the source code of this file. intљ . sphx2s (const double eul[5], int nphi, int ntheta, int spt, int sxy, const double phi[], const double theta[], double lng[], double lat[]) . ... sphs2x (const double eul[5], int nlng, int nlat, int sll, int spt, const double lng[], const double lat[], double phi[], double theta[]) . ... sphdpa (int nfield, double lng0, double lat0, const double lng[], const double lat[], double dist[], double pa[]) . ...

... Bad Astronomy . Misconceptions . ... Bad Astronomy : The Moon only shows one face to us because it is not rotating. Better astronomy : The Moon only shows one face because it is rotating, once every time it revolves around the Earth. ... Place the Moon model on the table about 30 centimeters (one foot) away with the X facing the Earth model. ... You'll see that to keep the X facing the Earth model, you have to rotate the Moon model as it goes around the Earth model . ... 2008 Phil Plait. ...

... Parameter Mand Type Default Constraints siamset yes string /data/cerd/ CCF /ccfdev/packages/xmm- siam /XMM BORESIGHT for siam .matrix0005. CCF DataSet containing the SIAM angles in BoreSight CCF format. (see comments) ry yes oat 0 3600{3600 shift of source in the FOV of the instrument corresponding to a rotation of the space-craft around the Y-axis in arcsec rz yes oat 0 3600{3600 shift of source in the FOV of the ... SIAM matrix, but formatted as a BoreSight constituent. ...

... One of this year's largest mass ejections from the Sun's atmosphere was recorded last Sunday by TESIS telescopes aboard the CORONAS-PHOTON satellite ( video - wmv 4.3 MB ). ... Over the course of a week, two gigantic solar prominences were simultaneously ejected from the surface of the Sun. ... Earth will not feel the Sun's influence either. ... The TESIS observatory ї TESIS: www.tesis.lebedev.ru . ... One of this year's largest mass ejections from the Sun's atmosphere (movie WMV, 4.3 MB) . ...

Astronotes Armagh Planetarium's Stellar Blog! ... Armagh Planetarium . ... Moon . ... Space Flight . ... Science Fiction . UFOs and Fringe Science . Monthly Sky Notes . ... NASA's Cassini spacecraft obtained this image of Saturn's moon Helene on June 18, 2011. Image credit: NASA/JPL-Caltech/Space Science Institute) . ... Your email address will not be published. ... Email * . ... Here you will find the latest news and views from the fascinating worlds of astronomy and space exploration. ...

... They are concerned with Attitude Control System of the spacecraft, satellite visibility from tracking stations, limits on the satellite autonomous operations during the orbit, and needs for auxiliary operations with the spacecraft. ... Among the operational constraints the most important one is the number of programmed slews per orbit, which determines the maximum number of radio sources to be observed during one orbit. ... System temperature (K) . ... Progress of the RadioAstron Project in Pictures...

SINGULAR POINTS IN THE SOLAR CHROMOSPHERE . ... In the structure of the solar chromosphere, containing information on the configuration of the magnetic field, we have found and identified all the main types of the singular points ( see Fig. 1 ), which are known as inherent features of the 2-D vector field. ... The main types of the singular points are the node, the focus, the center, and the saddle. ... Singular point of the focus type in the solar chromosphere. ...

Operations in Point operations use the pointer to query sets about points, delete points in a set, and move points. In all cases where interaction is required, pressing the right mouse button with the pointer in the drawing area cancels the operation. ... Report on a point in a set . ... Press the left mouse button. ... Press Delete point with the left mouse button to activate. ... Move the pointer to the new location and press the left mouse button again to register the point's new location. ...

Russian SHAREABLE DATA CENTER Institute of Solar-Terrestial Physics SB RAS . ... The algorithm and appropriate program for decametric radiosignal propagation conditions prediction for paths from 500 to 9000 km have been developed at ISTP SB on the basis of normal wave method (AltyntsevaB.I,Iliyin N.V., Kurkin V.I. and others //Decameters channel simulation on the base of normal wave method . ... Solar activity indices are chosen automatically from the prediction date from the database . ...

... Direct data transmission rate (Mbps) . ... the density of electron fluexs with energies in four bands from 0.04 MeV to 1.7 MeV; . ... sensor (TV, IR) data and heliogeophisical information (HGI) transmission to data receiving and processing centers at a rate of up to 2.56 Mbps; . ... 1.76 GHz - TV- and heliogeophysical information and DCLI's data transmission to data receiving and processing centers; . 7.5 GHz - TV- and heliogeophisical data transmission to data receiving and processing centers; . ...

... A small yet powerful planning and scheduling toolkit has been built for the Submillimeter Wave Astronomy Satellite ( SWAS ) Small Explorer spacecraft. ... The simple design, minimal resource requirements and easy extensibility of the SWAS planning and scheduling toolkit should make it useful for other space astronomy missions. ... The relatively severe time and manpower constraints for the development of the SWAS Planning and Scheduling toolkit have forced it to remain small and simple. ...