... The force F of gravity between two objects of mass m and M, whose centres are a distance r apart, is given by Newton's famous equation: [pic], where G = 6.67(10-11 N m2 kg-2, and F is measured in Newtons. So, the force in orbit Fo is weaker than the force on the Earth's surface F0 by the ratio: [pic] where the radius of the Earth is 6,400 km, and the orbit is 1000 km above the Earth's surface. ... Energy Considerations Another way to see all this is to consider the energy of an object in orbit. ...

... Space flight . ... Simulators . ... Space camp . Space Hotel . ... Virtual reality-based stand for ISS crew training is used for cosmonauts pre-training preparation at different stages of training for the space flight. ... At present cosmonauts and astronauts can work both with the SM and FGB images independently and having them in mated state. ... Info: Industry news On-line Data Company ATLAS news Events We in press Contact . Copyright 2000-2016 ATLAS Aerospace . ...

... Mass . 17a. Measuring Mass . ... A medium-size (1.25 inch wide) binder clip, as is used in offices to hold papers together--the type made of flat blue steel, with two wire handles. ... The theory predicts that the oscillation period should be proportional to the square root of the oscillating mass, including the mass of the clip. Note that gravity plays no part here: the oscillation period would be the same on the Moon or in zero-g. Denoting square root by SQRT, we have . ...

... A lightweight stick with two balls of equal weight at its end obviously has its CG in the middle. When one ball is twice the weight of the other, the CG divides the distance between them by a ratio 1:2, in a way that makes it closer to the heavier mass ( see figure ). ... Even though the balls are separate, one can speak of their common center of gravity, on the line connecting their centers, 1/3 of the distance from the center of the heavier ball. ...

... Earth at Twilight . ... It looks like a double comet, but Comet PanSTARRS (C/2011 L4) is just offering skygazers a Messier moment. Outward bound and fading in this starry scene, the well-photographed comet is remarkably similar in brightness to M31, the Andromeda Galaxy. ... Comet PANSTARRS and the Andromeda Galaxy . ... Currently, comet PANSTARRS is passing nearly in front of the galaxy Andromeda. Coincidentally, both comet and galaxy appear now to be just about the same angular size. ...

... This distance is equivalent to 3.26 light years. ... The Universe was now a large place and the intrinsic energy output of the stars had to be huge in order that their light could reach us. ... Newton implicitly assumes space is flat . ... An Orbit in Curved Space This is a prediction made by General Relativity and confirmed by direct observation of Mercury. The Ant Universe in Flat Space . ... Hubble noticed a correlation between recessional velocity and distance. ...

... Bad Astronomy . ... Bitesize Astronomy . ... Keep Bad Astronomy close to your heart, and help make me filthy rich. ... How many times have you heard the phrases "escape from Earth's gravity" and "zero gravity"? ... Gravity goes on forever, and there is no place in the Universe where there isn't some gravitational force. Anything with mass has gravity. ... So there really is no place in the Universe where there is zero gravity, except in the annals of Bad Astronomy. 2008 Phil Plait. ...

... 2013 April 8 . A Redshift Lookup Table for our Universe . ... One such table is listed above , where redshift z is listed in the first and last columns, while the corresponding universe age in billions of years is listed in the central column. ... Although stars in our galaxy are effectively at cosmological redshift zero, the most distant supernova e seen occur out past redshift one , which the above chart shows occurred when the universe was approximately half its present age. ... About APOD | ...

3) Planets and Brown Dwarfs . ... By its nature, this method is most sensitive to massive planets orbiting close to their stars. ... That means that some of the more massive extrasolar planets could actually be brown dwarfs (although the statistics of the finds suggest that most of them are not). ... Another possible difference between brown dwarfs and massive planets is how they are born. ... They would base the fundamental definition on the mode of formation: a planet is built from planetesimals. ...

Blackholes Forum Message . Forums: . ... Discussion Forums | Blackholes I | ... The “space-time” Isn’t Actual Reality . Forum List | ... Post Message | ... There are shown that the “Space-time”, introduced by Minkovsky and Einstein, it’s a false physical reality only. ... www.astronomy.net . About Astronomy Net | Advertise on Astronomy Net | ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... In Spiral . Between spiral . ... Center of vortices . ... to density exterema . ...

In order to measure the density of the Universe, it is necessary to sample a region that is larger than the scale on which the Universe becomes approximately homogeneous. ... When applied to clusters of galaxies we find a mass to luminosity ratio that implies a density of the Universe that is about 0.3 times the critical density. ... Thus the mass-to-muinosity ratio appears to vary with the size of the region measured, from 3 in the solar neighborhood to 30 in galaxies to 300 in clusters of galaxies. ...

... How much brighter is the Sun as viewed from the planet Mercury as compared to Earth ? ... Actually, all of these questions can be answered through a very simple mathematical relationship known as the inverse square law. ... As the distance from the Sun increases the surface area of the sphere grows by the square of the distance. ... Common sense tells us that the Sun will be brighter and the inverse square law tells us how much brighter. ... gr = 0.912 G or 91.2% gravity felt at Earth's surface. ...

Lecture 15 Plan for Lecture Will complete derivation of Angular Diameter Distance and then go through a specific example-- Einstein de Sitter universe Then look at what it becomes in a ` flat ' universe (currently favoured) Then discuss velocities and the Hubble Law (actually derive this) And then specific examples of what the data on Luminosity distance seems to be saying about the dynamics of the universe Finally, a new topic -- horizons, in ... Also, k = 0 (for EdS) S () . ...

... THE SIMPLEST MODEL. ... 13, Moscow 119992, Russia E-mail: san@sai.msu.ru Abstract: The analysis of the simplest model shows that an asteroid ­ rubble pile evolves, depending on the parameter V2d (where V is the average velocity of fragments and d is the average distance between fragments), either as a conglomerate of "independent mutually gravitating clusters" (when V2d < fm, where f is the gravitational constant and m is the average mass of a fragment) or as a "receding cluster" (when V2d > fm). ...

The sky background can contribute significant Poisson noise in broad and medium band filters, and must be taken into account during noise calculations. The actual sky b1rightness depends on the heliocentric ecliptic coordinates (latitude and longitude) in a manner summarized in Table 6.3 . ... 22.4 . ... Values for other filters or sky brightnesses can be computed from Table 6.2 , Table 6.1 , Table 6.3 , and Equation 6.2. Table 6.4: Sky Count Rate per Pixel (P sky ). ...

... NOW HERE'S THE BEEF: The VSWR tolerance of a transmitter like ours depends on a number of potential problem areas, such as plate voltage swing, voltages and currents in the elements of the matching network and filter, voltage and current tolerance at nodes in the Heliax line, etc. ... The screen grid has a finite power dissipation limit (before it starts melting!), and this limit is given on the tube datasheet. Transmitter metering should show both screen voltage and screen current. ...

Authors: V.A. Marsakov , Yu.G. Shevelev , . Journal: 1988, Astron Zh. ... Absolute magnitudes, metallicities, effective temperatures, surface gravities, distances, and tangential velocities are calculated for 5498 F stars with homogeneous data on uvby photometry and proper motion, and placed within 80 pc from the Sun. Components of space velocities, eccentricities of galactic orbits, perigalactic and apogalactic distances, and maximal remotness from galactic plane are presented for 1787 stars. ...

... It is expected that the offset for each CCD's pulse-height calibration will depend on the actual light background, which is a function of the aspect of the telescope. rgsoffsetcalc utilizes the simultaneously transmitted diagnostic mode data (the Q-dumps ) and determines the offset per diagnostic dataset. These are written together with time stamps into a calibration data file, which must be explicitly presented to the CAL by each task that would have them override the static calibration data. ...

... Exposure Time Calculator (ETC) . Survey processing . ... VISTA is a 4-m class wide field survey telescope for the southern hemisphere, equipped with a near infrared camera (1.65 degree diameter field of view at VISTA's nominal pixel size) containing 67 million pixels of mean size 0.34 arcsec and available broad band filters at Z,Y,J,H,K s and a narrow band filter at 1.18 micron. A wide field visible camera, if constructed, could also be used on VISTA. ... Tile . ... ESO VISTA Public Surveys . ...