Encyclopedia - Very Large Telescope: Encyclopedia - Very Large Telescope
The Very Large Telescope Project (VLT) consists of a system of four separate optical telescopes (the Antu telescope, the Kueyen telescope...   » Read the article

Encyclopedia - Karyotype: Encyclopedia - Karyotype
A karyotype is the complete set of all chromosomes of a cell of any living organism. The chromosomes are arranged and displayed (often on...   » Read the article

Encyclopedia - Metre: Encyclopedia - Metre
The metre (Commonwealth English) or meter (American English) (symbol: m) is the SI base unit of length. It is defined as the length of th...   » Read the article

Encyclopedia - Very Long Baseline Interferometry: Encyclopedia - Very Long Baseline Interferometry
Very Long Baseline Interferometry (VLBI) is a type of interferometry in which the data received at each antenna in the array is paired wi...   » Read the article

Encyclopedia - Betelgeuse: Encyclopedia - Betelgeuse
Betelgeuse (Alpha (α) Orionis) is a semiregular variable star located about 450 light-years away [1]. It is the second brightest star in...   » Read the article

Encyclopedia - Virgo Physics: Encyclopedia - Virgo Physics
In physics, VIRGO is a project of France and Italy, a Michelson laser interferometer that is analogous to LIGO. VIRGO physics - External...   » Read the article

Encyclopedia - Aperture Masking Interferometry: Encyclopedia - Aperture Masking Interferometry
Aperture Masking Interferometry is a form of speckle interferometry, allowing diffraction limited imaging from ground based telescopes. T...   » Read the article

Encyclopedia - Vacuum: Encyclopedia - Vacuum
For other uses, see vacuum cleaner and Vacuum (musical group). The root of the word vacuum is the Latin word vacuus (pl. vacua) which mea...   » Read the article

Encyclopedia - Merlin: Encyclopedia - Merlin
The Multi-Element Radio Linked Interferometer Network (MERLIN) is an array of radio telescopes spread across Britain. The array is run fr...   » Read the article

Encyclopedia - Albert Abraham Michelson: Encyclopedia - Albert Abraham Michelson
Albert Abraham Michelson, (pronunciation anglicized as "Michael-son", December 19, 1852 - May 9, 1931), was a Prussian-born American phys...   » Read the article

Encyclopedia - Albert Abraham Michelson: Encyclopedia Ii - Albert Abraham Michelson - Speed Of Light
Albert Abraham Michelson - Early measurements. As early as 1877, while still an officer in the US Navy, Michelson started planning a re...   » Read the article

Encyclopedia - Mount Wilson Observatory: Encyclopedia Ii - Mount Wilson Observatory - 60 Inch 1.5 M Hale Telescope
George Ellery Hale received the 60 inch (1.5 m) blank mirror, cast by Saint Gobain in France, in 1896 as a gift from his father, William ...   » Read the article

Encyclopedia - Aether Drag Hypothesis: Encyclopedia Ii - Aether Drag Hypothesis - Historical Importance
The aether drag hypothesis is historically important because it was one of the reasons why Newton's corpuscular theory of light was repla...   » Read the article

Encyclopedia - Speed Of Light: Encyclopedia Ii - Speed Of Light - Physics
Speed of light - Constant velocity from all reference frames. It is important to realise that the speed of light is not a "speed limit"...   » Read the article

Encyclopedia - Ligo: Encyclopedia Ii - Ligo - Mission
LIGO's mission is to observe directly gravitational waves of cosmic origin. These waves were first predicted by Einstein's Theory of Gene...   » Read the article

Encyclopedia - Jan Oort: Encyclopedia Ii - Jan Oort - Honors
Awards Bruce Medal in 1942 Gold Medal of the Royal Astronomical Society in 1946 Henry Norris Russell Lectureship in 1951 Named after hi...   » Read the article

Encyclopedia - Betelgeuse: Encyclopedia Ii - Betelgeuse - Distinguishing Characteristics
Several features of Betelgeuse are of particular interest to astronomers. It was one of the first stars to have its diameter measured wit...   » Read the article

Encyclopedia - Metre: Encyclopedia Ii - Metre - History
The word metre is from the Greek metron (μετρον), "a measure" via the French mètre. Its first recorded usage in English is from 17...   » Read the article

Encyclopedia - Observational Astronomy: Encyclopedia Ii - Observational Astronomy - Observation Tools
The key instrument of nearly all modern observational astronomy is the telescope. This serves the dual purposes of gathering more light s...   » Read the article

Encyclopedia - Submillimetre Astronomy: Encyclopedia Ii - Submillimetre Astronomy - Submillimetre Astronomy From Space
Space-based observations at the submillimetre wavelengths remove the ground-based limitations of atmospheric absorption. The Submillimete...   » Read the article

Encyclopedia - Telescope: Encyclopedia Ii - Telescope - History
The first telescopes may have been Assyrian crystal lenses. Article The Visby lenses tentatively suggest that the technology was known to...   » Read the article

Encyclopedia - James Clerk Maxwell Telescope: Encyclopedia Ii - James Clerk Maxwell Telescope - History
In the late 1960s the Astronomy Committee of the UK's Science Research Council (SRC, for forerunner of PPARC) considered the importance o...   » Read the article

Encyclopedia - Afshar Experiment: Encyclopedia Ii - Afshar Experiment - Athe Duality Relation For Beginners
Wave-particle duality is considered to be one of the distinguishing characteristics of quantum mechanics, whose theoretical and experimen...   » Read the article

Encyclopedia - Very Large Telescope: Encyclopedia Ii - Very Large Telescope - General Information
The VLT consists of a cluster of four large (8.2 meter diameter) telescopes, and an interferometer (VLTI) which is used to resolve fine f...   » Read the article

Encyclopedia - Michelson-morley Experiment: Encyclopedia Ii - Michelson-morley Experiment - The Most Famous Failed Experiment
Ironically, after all this thought and preparation, the experiment became what might be called the most famous failed experiment to date....   » Read the article

Encyclopedia - Vacuum: Encyclopedia Ii - Vacuum - Historical Interpretation
Historically, there has been much dispute over whether such a thing as a vacuum can exist. Ancient Greek philosophers did not like to adm...   » Read the article

Encyclopedia - Merlin: Encyclopedia Ii - Merlin - The E-merlin Upgrade
MERLIN currently uses microwave links to send astronomical data back from the remote stations. These links have a limited bandwidth so mu...   » Read the article

Encyclopedia - Very Large Telescope: Encyclopedia Ii - Very Large Telescope - Interferometry And The Vlti
Most interferometry will be done using 1.8 meter Auxiliary Telescopes (ATs), which will be dedicated to full-time interferometric measure...   » Read the article

Encyclopedia - Afshar Experiment: Encyclopedia Ii - Afshar Experiment - Overview
The principle of complementarity states that two complementary physical observables cannot both be measured for any given quantum particl...   » Read the article

Encyclopedia - Telescope: Encyclopedia Ii - Telescope - Types
Telescopes are broadly classified into two main types. Optical telescopes Radio telescopes Optical telescopes are also divided into two...   » Read the article

Encyclopedia - Telescope: Encyclopedia Ii - Telescope - Telescope Mountings
A simple telescope mount is an altitude-azimuth or altazimuth mount. It is similar to that of a surveying transit. A fork rotates in azim...   » Read the article

Encyclopedia - Telescope: Encyclopedia Ii - Telescope - Research Telescopes
Most large research telescopes can operate as either a Cassegrain telescope (longer focal length, and a narrower field with higher magnif...   » Read the article

Encyclopedia - James Clerk Maxwell Telescope: Encyclopedia Ii - James Clerk Maxwell Telescope - Instrumentation
The JCMT carries two types of instruments - broadband continuum detectors and spectral-line receivers. The older continuum single pixel U...   » Read the article

Encyclopedia - Afshar Experiment: Encyclopedia Ii - Afshar Experiment - Experimental Setup And Afshar's Interpretation
The experiment uses a setup similar to that for the double-slit experiment. In Afshar's variant, light generated by a laser passes throug...   » Read the article

Encyclopedia - Speed Of Light: Encyclopedia Ii - Speed Of Light - Communications
The speed of light is of relevance to communications. For example, given that the equatorial circumference of the Earth is 40,075 km...   » Read the article

Encyclopedia - Speed Of Light: Encyclopedia Ii - Speed Of Light - History
Until relatively recent times, the speed of light was largely a matter of conjecture. Empedocles maintained that light was something in m...   » Read the article

Encyclopedia - Afshar Experiment: Encyclopedia Ii - Afshar Experiment - History
Shahriar S. Afshar's experimental work was done initially at the Institute for Radiation-Induced Mass Studies and later reproduced at Har...   » Read the article

Encyclopedia - Speed Of Light: Encyclopedia Ii - Speed Of Light - Overview
According to standard modern physical theory, all electromagnetic radiation, including visible light, propagates (or moves) at a constant...   » Read the article

Encyclopedia - Michelson-morley Experiment: Encyclopedia Ii - Michelson-morley Experiment - Fallout
This result was rather astounding and not explainable by the then-current theory of wave propagation in a static aether. Several explanat...   » Read the article

Encyclopedia - Vacuum: Encyclopedia Ii - Vacuum - Vacuum In Space
Much of outer space has the density and pressure of an almost perfect vacuum. It is cold and has no friction. The properties of the vacuu...   » Read the article

Encyclopedia - Vacuum: Encyclopedia Ii - Vacuum - The Quantum-mechanical Vacuum
Even an ideal vacuum, thought of as the complete absence of anything, will not in practice remain empty. One reason is that the walls of ...   » Read the article

Encyclopedia - Metre: Encyclopedia Ii - Metre - Si Prefixes Applied To The Metre
The metre may be used with some SI prefixes. ... See also:Metre, Metre - SI prefixes applied to the metre, Metre - Conversions, Metre ...   » Read the article

Encyclopedia - Betelgeuse: Encyclopedia Ii - Betelgeuse - Origin Of The Name Betelgeuse
The name is a corruption of the Arabic يد الجوزا yad al-jawzā, or "hand of the central one". Jauza, the central one, initially r...   » Read the article

Encyclopedia - Vacuum: Encyclopedia Ii - Vacuum - Ultra-high Vacuum
Even higher vacuums are possible, but they generally require custom-built equipment, strict operational procedures, and a fair amount of ...   » Read the article

Encyclopedia - Vacuum: Encyclopedia Ii - Vacuum - High Vacuum
Fortunately, once the pressure has dropped below 1 kPa or so, another vacuum pumping technique becomes possible. Matter flows differently...   » Read the article

Encyclopedia - Telescope: Encyclopedia Ii - Telescope - Imperfect Images
No telescope can form a perfect image. Even if a reflecting telescope could have a perfect mirror, or a refracting telescope could have a...   » Read the article

Encyclopedia - Vacuum: Encyclopedia Ii - Vacuum - Partial Vacuum
Physicists use the term partial vacuum to describe real-life non-ideal vacuum. A complete characterization of the physical state would re...   » Read the article

Encyclopedia - Vacuum: Encyclopedia Ii - Vacuum - Degrees Of Vacuum
As gas pressure decreases, the mean free path (MFP) of the gas molecules increases. When the MFP is greater than the chamber, pump, space...   » Read the article

Encyclopedia - Vacuum: Encyclopedia Ii - Vacuum - Creating A Vacuum
The easiest way to create an artificial vacuum is to expand the volume of a container. For example, your muscles expand your lungs to cre...   » Read the article

Encyclopedia - Albert Abraham Michelson: Encyclopedia Ii - Albert Abraham Michelson - Life
Michelson was born in Strzelno, Poland (then Strelno, Provinz Posen Kingdom of Prussia) in 1852, the son of a Jewish merchant. He moved t...   » Read the article

Encyclopedia - Mount Wilson Observatory: Encyclopedia Ii - Mount Wilson Observatory - 100 Inch 2.5 M Hooker Telescope
Hale immediately set about creating a larger telescope. John D. Hooker provided crucial funding for it, along with Carnegie. The Saint Go...   » Read the article

Encyclopedia - Observational Astronomy: Encyclopedia Ii - Observational Astronomy - Unaided Eye
Prior to the discovery of the telescope, early observational astronomy relied upon the unaided eye and various instruments for measuring ...   » Read the article

Encyclopedia - Observational Astronomy: Encyclopedia Ii - Observational Astronomy - Telescopes
Galileo Galilei was the first person to known to turn a telescope to the heavens and to record what he saw. Since that time, observationa...   » Read the article

Encyclopedia - Observational Astronomy: Encyclopedia Ii - Observational Astronomy - Optical Telescopes
For much of the history of observational astronomy, almost all observation has been performed in the visual spectrum with optical telesco...   » Read the article

Encyclopedia - Observational Astronomy: Encyclopedia Ii - Observational Astronomy - Other Instruments
In addition to examination of the universe in the optical spectrum, astronomers have increasingly been able to acquire information in oth...   » Read the article

Encyclopedia - Michelson-morley Experiment: Encyclopedia Ii - Michelson-morley Experiment - The Experiment
Michelson, though, had already seen a solution to this problem. His design, later known as an interferometer, sent a single source of mon...   » Read the article

Encyclopedia - Michelson-morley Experiment: Encyclopedia Ii - Michelson-morley Experiment - Measuring Aether
Each year, the Earth travels a tremendous distance in its orbit around the sun, at a speed of around 30 km/second, over 100,000 km per ho...   » Read the article

Encyclopedia - Ligo: Encyclopedia Ii - Ligo - Observatories
LIGO operates two gravitational wave observatories in unison: the Livingston Observatory in Livingston, Louisiana and the Hanford Observa...   » Read the article

Encyclopedia - Ligo: Encyclopedia Ii - Ligo - Operation
The primary interferometer at each site consists of mirrors suspended at each of the corners of the L; it is known as a power-recycled Mi...   » Read the article

Encyclopedia - Ligo: Encyclopedia Ii - Ligo - Observations
Based on current models of astronomical events, and the predictions of the general theory of relativity, gravitational waves that origina...   » Read the article

Encyclopedia - Observational Astronomy: Encyclopedia Ii - Observational Astronomy - Observing
A variety of data can be observed for each star. The position coordinates locate the star on the sky using the techniques of spherical as...   » Read the article