M1 image More About M1 Nice Color Picture . ... M16 image More About M16 HST image . ... M31 image More About M31 Nice Color Picture . ... M42 image ; M43 image More About M42/43 Nice Color CCD Picture . M51 image More About M51 Color Image of M51 M51 Supernova . M57 image More About M57 Nice Color CCD Picture Very Deep M57 Image . ... M81 image More About M81 M81 Supernova Ultraviolet Image of M81 More about Ultraviolet Imaging . M82 image More About M82 M82 False Color M82 True Color . ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Risks Comparable to NEOs . ... The Increasing Rate of Discovery of Asteroids . ... Comet and Asteroid Collision Probabilities . ... Extreme albedo comets and the impact hazard (PDF Format) . ... Asteroid Impact Animations . ... Workshop on Scientific Requirements for Mitigation of Hazardous Comets and Asteroids - 2002 . ... The Spaceguard Survey Report, 1992 (PDF) . Tsunami from Asteroid/Comet Impacts . ...

Galileo showed convincingly that heavy objects fell no faster that light ones. ... If an iron ball was pulled down with a much greater force than a wooden one of the same size, why didn't it fall any faster? ... 1) It is harder to lift. ... It is the fact that the loaded wagon has a greater mass that gives it a larger inertia , a larger tendency to oppose any change in its state of rest or of constant motion in a straight line. ... One important quantity was the body mass of the astronauts. ...

... Tonight's Sky . ... The Magazine . ... Observing . ... Magazine . ... Gravitational wave search provides insights into galaxy evolution and mergers . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Gravity's star-stripping force . ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ... Astronomy Magazine . ...

Comets necessarily obey the same physical laws as every other object. ... If one considers only two bodies -- either the Sun and a planet, or the Sun and a comet -- the smaller body appears to follow an elliptical path or orbit about the Sun, which is at one focus of the ellipse. ... Another quantity that is conserved is called angular momentum. ... Comets simply are bodies which in general have more angular momentum per unit mass than do planets and therefore move in more elongated orbits. ...

... This version of the GHRS Instrument Handbook has had significant rewriting, mostly to incorporate information about the proposal writing software called RPS2 . ... We anticipate that Cycle 6 will be the last for the GHRS. ... Because Cycle 6 is short for both the GHRS and FOS, it is STScI's intention to schedule spectroscopic observations early in Cycle 6 to the greatest extent possible so that as many FOS and GHRS programs may be completed as is possible. ... Cycle 6 and the End of the GHRS . ...

... Duchamp | ... Top | Duchamp is a solution to this problem of three-dimensional source finding. ... A list of the detections and their properties, as well as the input parameters that were used. [text file] . ... It can be downloaded in source format, in a gzipped tar archive. ... Changes from the previous version can be seen here (this file is included in the tar archive), while the archive files and documentation from the previous release versions are here , if you are really interested. ...

... Two new LBV stars have been discovered in the Andromeda Galaxy. ... In Figure 1 the spectral energy distributions for six stars are shown: upper row - the newly discovered LBV stars, middle row - two well-known LBV stars Var A-1 and AE And, the lower row - two new B[e]-supergiant stars in Andromeda. ... Infrared spectra of the stars in the Andromeda Galaxy: two classical LBVs Var A-1 and AE And, two new LBVs J004526.62 and J004051.59, and two new B[e]-supergiants J004417.10 and J004444.52. ...

Pulsar - the neutrone star. ... Its physical properties are greatly changed. ... Naturally after the discovery of pulsar connection with the remains of the supernew star outbursts it was supposed that the pulsars and the neutron stars are the same objects. ... In the external layer of a neutron star, where the substance dense is not so great to break the cores; they may from the hard chip structure, which at the pulsar rotation decreasing is broken the starquake. ...

... Up: Data Analysis and Processing Techniques . ... Also, a method for quality control of CCD observations is suggested. ... Everyone who observes a celestial object using a CCD detects moving celestial objects as a ``by product''. ... We hope that our investigations may be useful for near-Earth space control and also for searches of the moving celestial objects through analysis of old and new CCD frames obtained at any amateur or professional astronomical observatory. ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2014 October 15 . Mysterious Changing feature on Titan . Image Credit: Cassini Radar Mapper , Cornell , JPL , ESA , NASA . Explanation: What is that changing object in a cold hydrocarbon sea of Titan? ... Subsequent observations in 2014 found the object remained -- but had changed! ... About APOD | ... A service of: ASD at NASA / GSFC . ...