... The general term for these waves is "Electromagnetic Waves". ... ASTR1001 Wavelengths · Electromagnetic waves, while all travelling at the same speed, can have different wavelengths (the distance between the crest of one wave and the next). ... Red Light: Wavelength 700nm Green Light: Wavelength 550nm Blue Light: Wavelength 400nm Ultra-Violet Light: Wavelength 300nm ASTR1001 The Electromagnetic Spectrum · Electromagnetic waves can have any wavelengths at all: anywhere from picometres to light-years....

Tired light models invoke a gradual energy loss by photons as they travel through the cosmos to produce the redshift-distance law. ... The tired light model can not produce a blackbody spectrum for the Cosmic Microwave Background without some incredible coincidences. ... So the CMB must have come from a far away part of the Universe, and its photons will thus lose energy by the tired light effect. ... Assume that the CMB starts out as a T = (1+z)*T_o = 2.998 K blackbody, which is the blue curve. ...

... ESO is building what will be the World's largest optical telescope array, The Very Large Telescope (VLT). The VLT Project organisation is responsible for the design and construction of the Unit Telescopes, including enclosures, optics, adapter-rotators and coating unit. ... Unit Telescopes Overview - This page is outdated, an update is in process. ... Secondary mirror (M2 Unit) - This page is outdated, an update is in process. ... Coating Unit - This page is outdated, an update is in process. ...

... Tonight's Sky . ... Observing . ... Sky this Month . ... Observing Podcasts . ... Astronomy for Kids . ... Sky Events . ... Why do physicists think gravity travels at the speed of light? ... According to Newton, gravity acts instantly that is, "action at a distance" and so, from that viewpoint, gravity travels at an infinite speed. Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ...

... Under certain conditions, like those in the nucleus of a QSO, all atoms can be made to emit light at particular wavelengths. ... If that source is approaching the observer, the wave is squashed up onto itself making the wavelength shorter. ... This is redshift. ... You can see how the section of the QSO spectrum which we observe changes with redshift. ... We then see how far we had to slide the observed spectrum along the scale to make it match and that is the objects redshift. ... The 2QZ team . ...

... Editor's note: This activity is both on the Astrocappella web site and the CD-ROM featured in this article. ... Every student can demonstrate the Doppler effect! ... splash out' ball** . ... Twist the 'splash out' ball open. ... This effect can occur with both sound and light, because both sound and light reveal wave- like behavior. ... The number of waves reaching an observer in one second is called the frequency. ... What has the Doppler shift told astronomers about the expansion of the universe? ...

EMBARGOED UNTIL: 9:20 AM CST, January 6, 1999 CONTACT: John Biretta Space Telecsope Science Institute, Baltimore, MD (Phone: (410) 338-4917; Internet: biretta@stsci.edu) HUBBLE DETECTS FASTER-THAN-LIGHT MOTION IN GALAXY M87 Astronomers reported today discovering clouds which appear to move many times faster than the speed of light, shooting out from the region of a black hole at the center of the M87 galaxy. ... It's an illusion created by the finite speed of light and rapid motion," Biretta said. ...

... The Eagle Nebula in Infrared . ... Credit Copyright: NASA / JPL-Caltech /N. Flagey (IAS/ SSC ) A. Noriega-Crespo ( SSC/Caltech ) Explanation: In visible light, the whole thing looks like an eagle . ... Shown above , the infrared image allows observers to peer through normally opaque dust and so better capture the full complexity of the Eagle Nebula star forming region. ... Publications with keywords: Eagle Nebula - infrared - Spitzer space telescope . ... The Eagle Nebula from Kitt Peak . ...

... The discovery of this radiopulsar is potentially important not only for confirming the theory of evolution of NS, but also for understanding processes occurring in stellar winds   from normal stars. After all, a radiopulsar orbiting in the semi-transparent stellar wind of a normal star is a sort of probe scanning an inhomogeneous plasma by pulsed radiation (Lipunov and Prokhorov, 1984)[ 110 ]. ... 1) absorption of radio waves (light curve); . ... This object is a radiopulsar orbiting a Be-star. ...

... The following charts/text are intended as tools for monitoring the Type Ia supernovae ( SNe ) event visually or photographically (utilizing telescope equipped CCD equipment).The files include: A replication of The Type Ia SNe , V- magnitude (with data point checks from other cited references)and color index (B-V) templete (to indicate a general color-related trend of the type Ia ... I believe this might help alleviate some of the problems involving the making of acceptable amateur light curves...

... We use the first XMM serendipitous source catalogue (1XMM) to compile a sample of normal X-ray galaxies . ... We combine our emission line sample with earlier works forming the most comprehensive X-ray selected galaxy sample for the study of the X-ray luminosity to the H? luminosity - a well-calibrated star-formation indicator - relation. ... We find that the X-ray luminosity strongly correlates with the H? luminosity, suggesting that the X-rays efficiently trace the star-formation. | ...

... While "First Light" was achieved at the second 8.2-m VLT Unit Telescope (UT2) ahead of schedule, UT1 produced its sharpest image so far. ... It had long been ESO's intention to provide "real" names to the four VLT Unit Telescopes, to replace the current, somewhat dry and technical designations as UT1 to UT4. ... The participants were left with the impression of mounting expectations, just four weeks before the first VLT Unit Telescope, Antu (UT1), will receive the first visiting astronomers. ...

Blackholes2 Forum Message . Forums: . ... Only Photons Travel At The Speed Of Light . Forum List | ... Posted by Richard Ruquist on October 21, 2004 12:29:14 UTC . ... Charge has mass and from the theory of relativity, they cannot travel at the speed of light. Radio waves are photons, a form of light. ... www.astronomy.net . About Astronomy Net | ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... Radio astronomers at Arecibo Observatory observe a wide variety of phenomena in the Milky Way and in other galaxies. ... Some REU projects are carried out on pre-existing data, and others rely on obtaining new data. ... Deriving a new shape model from existing radar images has been a popular student project in past years, and there are data sets that could be used for this. We are collecting thermal infrared emission data for many of the near-Earth asteroids that are also observed with radar. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... This shows the Sun, Moon and Earth (not to scale) together with the . ... They have tested the technique on the Earthshine, the light reflected from the Earth by the Moon, and showed that it can reveal the presence of life in our planet. ... This technique uses the fact that the light reflected from the planet is polarised, whereas that emitted by the star is not. ... Polarised light can tell us about the reflecting surface...

... For the past years I have been working on the problem of synthesis of light curves of close binary systems, consisting of a normal star and a compact object (point object with fixed X-ray luminosity). ... Possible existence of a bright spot on the disk's lateral surface is taken into account. ... The last of then will be published in Gordon and Breach Publishers ( Cherepashchuk A.M., Katysheva N.A., Khruzina T.S., Shugarov S.Yu. ... Cherepashchuk A.M., Katysheva N.A., Khruzina T.S., Shugarov S.Yu. ...

... Before the modern era of technological astronomy, to know anything about the Universe beyond our planet we relied on light. ... Historically the two rival ideas were that light was either a stream of tiny bullet-like particles or a wave wobbling its way through space. ... The light we see (visible light which is not the tautology it sounds) is only part of the electromagnetic spectrum, a great sweep of radiations which also includes radio, infra-red, ultra-violet, x-rays and gamma rays. ...

... X-rays are made up of photons that are emitted from stars, or quasars, or supernovae, the sun, or simply: anything that is undergoing a change either in size or temperature or giving out heat. ... in an X-ray binary star system, in which one normal star's orbit is crossed by a neutron star, when the neutron star by means of gravitational pull takes matter from the normal star X-rays form. ... Artists conception of a normal star (HDE 226868) and a black hole taking matter from the normal star. ...

... Bad Astronomy . Misconceptions . ... Bad Astronomy : "We're light years more advanced than our competition!" ... Even the closest astronomical object, the Moon, is 400,000 kilometers away! ... A beam of light will travel 9,500,000,000,000 kilometers in one year. This distance is defined as a light year ; the distance light travels in a year. ... This is another example of Bad Astronomy; like a light year, a parsec is a unit of distance, not time (to be specific, it equals 3.26 light years) . ...

... We describe the software tool bspec which models the dispersion and diffraction of light in the HST Faint Object Spectrograph. ... The HST Faint Object Spectrograph (FOS) uses blazed, ruled gratings and detectors that are sensitive over wide wavelength ranges. ... The program bspec has been developed to model the dispersion and diffraction of light in the FOS with an accuracy sufficient for the estimation of scattered light contamination in observed FOS data. ... We run bspec as follows: . ...