169 relations: Absorption spectroscopy, Acetone, Acetylene, Active galactic nucleus, Andromeda Galaxy, Angular resolution, Antony Hewish, Aperture synthesis, Asteroid, Astronomical interferometer, Astronomical spectroscopy, Astronomy, Atomic and molecular astrophysics, Australia Telescope National Facility, Autocorrelation, Balmer series, Bell Labs, Bengt Edlén, Betelgeuse, Binary star, Black body, Black hole, Blazed grating, Blueshift, Bragg's law, Buckminsterfullerene, C-type asteroid, Calcium, Calibration, Carousel, Charge-coupled device, Charles Augustus Young, Coma (cometary), Comet, Comet ISON, Continuous spectrum, Corona, Coronium, Dark matter, Dark nebula, Data cube, David J. Tholen, Discrete Fourier transform, Dispersion (optics), Dominion Observatory, Doppler effect, Edwin Hubble, Electromagnetic radiation, Electromagnetic spectrum, Electron, ..., Emission nebula, Emission spectrum, European Space Agency, Exoplanet, Expansion of the universe, Fluorescence, Forbidden mechanism, Fraunhofer lines, Fritz Zwicky, Galaxy, Galaxy cluster, Gas giant, Gas-discharge lamp, Graphite, Ground state, Gunn–Peterson trough, Gustav Kirchhoff, Helium, Highly charged ion, Hong-Yee Chiu, Hot Jupiter, Hubble Ultra-Deep Field, Hubble's law, Hydrogen, Hydrogen line, Infrared, Interferometry, Interstellar medium, Ira Sprague Bowen, Iron, Isaac Newton, James Stanley Hey, John Stanley Plaskett, Joseph Lade Pawsey, Joseph von Fraunhofer, Karl Guthe Jansky, Kelvin, Local Group, Luminosity, Lyman-alpha forest, Magnesium, Mars, Martin Ryle, Mercury (element), Messier 105, Metastability, Milky Way, Mineral, Moon, Nanometre, Nature (journal), Nebula, Nebulium, NGC 4550, NGC 4697, Nickel, Nobel Prize in Physics, Norman Lockyer, Nova, Orbital plane (astronomy), Organic compound, Oxygen, Ozone, Parallax, Peculiar velocity, Photographic plate, Photometry (astronomy), Pierre Janssen, Planet, Polycyclic aromatic hydrocarbon, Prism, Proportionality (mathematics), Proton, Quasar, Radial velocity, Radiant energy, Radio astronomy, Radio wave, Redshift, Reflection nebula, Robert Bunsen, Ruby Payne-Scott, S-type asteroid, Sagittarius A, Saturn, Sea interferometry, Silicate, Sodium, Solar System, Spectral flux density, Spectral line, Spectrograph, Spectrometer, Spectrophotometry, Spectroscopy, Spin (physics), Spiral galaxy, Star, Star system, Stefan–Boltzmann law, Stellar classification, Sun, Supernova, Titan (moon), Titanium, Ultraviolet, Venus, Vesto Slipher, Virgo Cluster, Visible spectrum, Walter Grotrian, Wave interference, White dwarf, Wien's displacement law, Wilhelm Wien, William Harkness, William Huggins, X-ray, X-type asteroid. Expand index (119 more) » « Shrink index
Absorption spectroscopy refers to spectroscopic techniques that measure the absorption of radiation, as a function of frequency or wavelength, due to its interaction with a sample.
Acetone (systematically named propanone) is the organic compound with the formula (CH3)2CO.
Acetylene (systematic name: ethyne) is the chemical compound with the formula C2H2.
An active galactic nucleus (AGN) is a compact region at the center of a galaxy that has a much higher than normal luminosity over at least some portion—and possibly all—of the electromagnetic spectrum, with characteristics indicating that the excess luminosity is not produced by stars.
The Andromeda Galaxy, also known as Messier 31, M31, or NGC 224, is a spiral galaxy approximately 780 kiloparsecs (2.5 million light-years) from Earth, and the nearest major galaxy to the Milky Way.
Angular resolution or spatial resolution describes the ability of any image-forming device such as an optical or radio telescope, a microscope, a camera, or an eye, to distinguish small details of an object, thereby making it a major determinant of image resolution.
Antony Hewish (born 11 May 1924) is a British radio astronomer who won the Nobel Prize for Physics in 1974 (together with fellow radio-astronomer Martin Ryle) for his role in the discovery of pulsars.
Aperture synthesis or synthesis imaging is a type of interferometry that mixes signals from a collection of telescopes to produce images having the same angular resolution as an instrument the size of the entire collection.
Asteroids are minor planets, especially those of the inner Solar System.
An astronomical interferometer is an array of separate telescopes, mirror segments, or radio telescope antennas that work together as a single telescope to provide higher resolution images of astronomical objects such as stars, nebulas and galaxies by means of interferometry.
Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light and radio, which radiates from stars and other celestial objects.
Astronomy (from ἀστρονομία) is a natural science that studies celestial objects and phenomena.
Atomic astrophysics is concerned with performing atomic physics calculations that will be useful to astronomers and using atomic data to interpret astronomical observations.
The Commonwealth Scientific and Industrial Research Organisation (CSIRO)'s radio astronomy observatories are collectively known as the Australia Telescope National Facility (ATNF), with the facility supporting Australia's research in radio astronomy.
Autocorrelation, also known as serial correlation, is the correlation of a signal with a delayed copy of itself as a function of delay.
The Balmer series or Balmer lines in atomic physics, is the designation of one of a set of six named series describing the spectral line emissions of the hydrogen atom.
Nokia Bell Labs (formerly named AT&T Bell Laboratories, Bell Telephone Laboratories and Bell Labs) is an American research and scientific development company, owned by Finnish company Nokia.
Bengt Edlén (2 November 1906, Gusum – 10 February 1993, Lund) was a Swedish professor of physics and astronomer who specialized in spectroscopy.
Betelgeuse, also designated Alpha Orionis (α Orionis, abbreviated Alpha Ori, α Ori), is the ninth-brightest star in the night sky and second-brightest in the constellation of Orion.
A binary star is a star system consisting of two stars orbiting around their common barycenter.
A black body is an idealized physical body that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence.
A black hole is a region of spacetime exhibiting such strong gravitational effects that nothing—not even particles and electromagnetic radiation such as light—can escape from inside it.
A blazed grating – also called echelette grating (from French échelle.
A blueshift is any decrease in wavelength, with a corresponding increase in frequency, of an electromagnetic wave; the opposite effect is referred to as redshift.
In physics, Bragg's law, or Wulff–Bragg's condition, a special case of Laue diffraction, gives the angles for coherent and incoherent scattering from a crystal lattice.
Buckminsterfullerene is a type of fullerene with the formula C60.
C-type (carbonaceous) asteroids are the most common variety, forming around 75% of known asteroids.
Calcium is a chemical element with symbol Ca and atomic number 20.
Calibration in measurement technology and metrology is the comparison of measurement values delivered by a device under test with those of a calibration standard of known accuracy.
A carousel (American English: from French carrousel and Italian carosello), roundabout (British English), or merry-go-round, is a type of amusement ride consisting of a rotating circular platform with seats for riders.
A charge-coupled device (CCD) is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value.
Charles Augustus Young (December 15, 1834 – January 4, 1908) one of the foremost solar spectroscopist astronomers in the United States, died of pneumonia after a brief illness, at his home in Hanover, New Hampshire, on 4 January 1908.
The coma is the nebulous envelope around the nucleus of a comet, formed when the comet passes close to the Sun on its highly elliptical orbit; as the comet warms, parts of it sublime.
A comet is an icy small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process called outgassing.
Comet ISON, formally known as C/2012 S1, was a sungrazing comet discovered on 21 September 2012 by Vitaly Nevsky (Виталий Невский, Vitebsk, Belarus) and Artyom Novichonok (Артём Новичонок, Kondopoga, Russia).
In physics, a continuous spectrum usually means a set of attainable values for some physical quantity (such as energy or wavelength) that is best described as an interval of real numbers, as opposed to a discrete spectrum, a set of attainable values that is discrete in the mathematical sense, where there is a positive gap between each value and the next one.
A corona (Latin, 'crown') is an aura of plasma that surrounds the Sun and other stars.
Coronium, also called newtonium, was the name of a suggested chemical element, hypothesised in the 19th century.
Dark matter is a theorized form of matter that is thought to account for approximately 80% of the matter in the universe, and about a quarter of its total energy density.
A dark nebula or absorption nebula is a type of interstellar cloud that is so dense that it obscures the light from objects behind it, such as background stars and emission or reflection nebulae.
In computer programming contexts, a data cube (or datacube) is a multi-dimensional ("n-D") array of values.
David James Tholen (born 1955) is an American astronomer at the Institute for Astronomy of the University of Hawaii.
In mathematics, the discrete Fourier transform (DFT) converts a finite sequence of equally-spaced samples of a function into a same-length sequence of equally-spaced samples of the discrete-time Fourier transform (DTFT), which is a complex-valued function of frequency.
In optics, dispersion is the phenomenon in which the phase velocity of a wave depends on its frequency.
The Dominion Observatory was an astronomical observatory in Ottawa, Ontario that operated from 1902 to 1970.
The Doppler effect (or the Doppler shift) is the change in frequency or wavelength of a wave in relation to observer who is moving relative to the wave source.
Edwin Powell Hubble (November 20, 1889 – September 28, 1953) was an American astronomer.
In physics, electromagnetic radiation (EM radiation or EMR) refers to the waves (or their quanta, photons) of the electromagnetic field, propagating (radiating) through space-time, carrying electromagnetic radiant energy.
The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies.
The electron is a subatomic particle, symbol or, whose electric charge is negative one elementary charge.
An emission nebula is a nebula formed of ionized gases that emit light of various wavelengths.
The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to an atom or molecule making a transition from a high energy state to a lower energy state.
The European Space Agency (ESA; Agence spatiale européenne, ASE; Europäische Weltraumorganisation) is an intergovernmental organisation of 22 member states dedicated to the exploration of space.
An exoplanet or extrasolar planet is a planet outside our solar system.
The expansion of the universe is the increase of the distance between two distant parts of the universe with time.
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation.
In spectroscopy, a forbidden mechanism (forbidden transition or forbidden line) is a spectral line associated with absorption or emission of light by atomic nuclei, atoms, or molecules which undergo a transition that is not allowed by a particular selection rule but is allowed if the approximation associated with that rule is not made.
In physics and optics, the Fraunhofer lines are a set of spectral lines named after the German physicist Joseph von Fraunhofer (1787–1826).
Fritz Zwicky (February 14, 1898 – February 8, 1974) was a Swiss astronomer.
A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter.
A galaxy cluster, or cluster of galaxies, is a structure that consists of anywhere from hundreds to thousands of galaxies that are bound together by gravity with typical masses ranging from 1014–1015 solar masses.
A gas giant is a giant planet composed mainly of hydrogen and helium.
Gas-discharge lamps are a family of artificial light sources that generate light by sending an electric discharge through an ionized gas, a plasma.
Graphite, archaically referred to as plumbago, is a crystalline allotrope of carbon, a semimetal, a native element mineral, and a form of coal.
The ground state of a quantum mechanical system is its lowest-energy state; the energy of the ground state is known as the zero-point energy of the system.
In astronomical spectroscopy, the Gunn–Peterson trough is a feature of the spectra of quasars due to the presence of neutral hydrogen in the Intergalactic Medium (IGM).
Gustav Robert Kirchhoff (12 March 1824 – 17 October 1887) was a German physicist who contributed to the fundamental understanding of electrical circuits, spectroscopy, and the emission of black-body radiation by heated objects.
Helium (from lit) is a chemical element with symbol He and atomic number 2.
Highly charged ions (HCI) are ions in very high charge states due to the loss of many or most of their bound electrons by energetic collisions or high-energy photon absorption.
Hong-Yee Chiu is an American astrophysicist and successful publisher of EHGBooks micro-publishing company, born in Shanghai in October 1932.
Hot Jupiters are a class of gas giant exoplanets that are inferred to be physically similar to Jupiter but that have very short orbital period (P The close proximity to their stars and high surface-atmosphere temperatures resulted in the moniker "hot Jupiters". Hot Jupiters are the easiest extrasolar planets to detect via the radial-velocity method, because the oscillations they induce in their parent stars' motion are relatively large and rapid compared to those of other known types of planets. One of the best-known hot Jupiters is 51 Pegasi b. Discovered in 1995, it was the first extrasolar planet found orbiting a Sun-like star. 51 Pegasi b has an orbital period of about 4 days.
The Hubble Ultra-Deep Field (HUDF) is an image of a small region of space in the constellation Fornax, containing an estimated 10,000 galaxies.
Hubble's law is the name for the observation in physical cosmology that.
Hydrogen is a chemical element with symbol H and atomic number 1.
The hydrogen line, 21-centimeter line or H I line refers to the electromagnetic radiation spectral line that is created by a change in the energy state of neutral hydrogen atoms.
Infrared radiation (IR) is electromagnetic radiation (EMR) with longer wavelengths than those of visible light, and is therefore generally invisible to the human eye (although IR at wavelengths up to 1050 nm from specially pulsed lasers can be seen by humans under certain conditions). It is sometimes called infrared light.
Interferometry is a family of techniques in which waves, usually electromagnetic waves, are superimposed causing the phenomenon of interference in order to extract information.
In astronomy, the interstellar medium (ISM) is the matter and radiation that exists in the space between the star systems in a galaxy.
Ira Sprague Bowen (December 21, 1898 – February 6, 1973) was an American physicist and astronomer.
Iron is a chemical element with symbol Fe (from ferrum) and atomic number 26.
Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, astronomer, theologian, author and physicist (described in his own day as a "natural philosopher") who is widely recognised as one of the most influential scientists of all time, and a key figure in the scientific revolution.
James Stanley Hey FRS (3 May 1909 – 27 February 2000) was an English physicist and radio astronomer.
John Stanley Plaskett (November 17, 1865 – October 17, 1941) was a Canadian astronomer.
Joseph Lade Pawsey (14 May 1908 – 30 November 1962) was an Australian scientist, radiophysicist and radio astronomer.
Joseph Ritter von Fraunhofer (6 March 1787 – 7 June 1826) was a Bavarian physicist and optical lens manufacturer.
Karl Guthe Jansky (October 22, 1905 – February 14, 1950) was an American physicist and radio engineer who in August 1931 first discovered radio waves emanating from the Milky Way.
The Kelvin scale is an absolute thermodynamic temperature scale using as its null point absolute zero, the temperature at which all thermal motion ceases in the classical description of thermodynamics.
The Local Group is the galaxy group that includes the Milky Way.
In astronomy, luminosity is the total amount of energy emitted per unit of time by a star, galaxy, or other astronomical object.
In astronomical spectroscopy, the Lyman-alpha forest is a series of absorption lines in the spectra of distant galaxies and quasars arising from the Lyman-alpha electron transition of the neutral hydrogen atom.
Magnesium is a chemical element with symbol Mg and atomic number 12.
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.
Sir Martin Ryle (27 September 1918 – 14 October 1984) was an English radio astronomer who developed revolutionary radio telescope systems (see e.g. aperture synthesis) and used them for accurate location and imaging of weak radio sources.
Mercury is a chemical element with symbol Hg and atomic number 80.
Messier 105 (also known as M105 and NGC 3379) is an elliptical galaxy in the constellation Leo.
In physics, metastability is a stable state of a dynamical system other than the system's state of least energy.
The Milky Way is the galaxy that contains our Solar System.
A mineral is a naturally occurring chemical compound, usually of crystalline form and not produced by life processes.
The Moon is an astronomical body that orbits planet Earth and is Earth's only permanent natural satellite.
The nanometre (International spelling as used by the International Bureau of Weights and Measures; SI symbol: nm) or nanometer (American spelling) is a unit of length in the metric system, equal to one billionth (short scale) of a metre (m).
Nature is a British multidisciplinary scientific journal, first published on 4 November 1869.
A nebula (Latin for "cloud" or "fog"; pl. nebulae, nebulæ, or nebulas) is an interstellar cloud of dust, hydrogen, helium and other ionized gases.
Nebulium was a proposed element found in astronomical observation of a nebula by William Huggins in 1864.
NGC 4550 is a barred lenticular galaxy located in the constellation of Virgo that can be seen with amateur telescopes.
NGC 4697 (also known as Caldwell 52) is an elliptical galaxy some 40 to 50 million light-years away in the constellation Virgo.
Nickel is a chemical element with symbol Ni and atomic number 28.
The Nobel Prize in Physics (Nobelpriset i fysik) is a yearly award given by the Royal Swedish Academy of Sciences for those who conferred the most outstanding contributions for mankind in the field of physics.
Sir Joseph Norman Lockyer, KCB FRS (17 May 1836 – 16 August 1920), known simply as Norman Lockyer, was an English scientist and astronomer.
A nova (plural novae or novas) or classical nova (CN, plural CNe) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star, that slowly fades over several weeks or many months.
The orbital plane of a revolving body is the geometric plane on which its orbit lies.
In chemistry, an organic compound is generally any chemical compound that contains carbon.
Oxygen is a chemical element with symbol O and atomic number 8.
Ozone, or trioxygen, is an inorganic molecule with the chemical formula.
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines.
Peculiar motion or peculiar velocity refers to the velocity of an object relative to a rest frame — usually a frame in which the average velocity of some objects is zero.
Photographic plates preceded photographic film as a capture medium in photography.
Photometry is a technique of astronomy concerned with measuring the flux, or intensity of an astronomical object's electromagnetic radiation.
Pierre Jules César Janssen (22 February 1824 – 23 December 1907), also known as Jules Janssen, was a French astronomer who, along with English scientist Joseph Norman Lockyer, is credited with discovering the gaseous nature of the solar chromosphere, and with some justification the element helium.
A planet is an astronomical body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.
Polycyclic aromatic hydrocarbons (PAHs, also polyaromatic hydrocarbons or polynuclear aromatic hydrocarbons) are hydrocarbons—organic compounds containing only carbon and hydrogen—that are composed of multiple aromatic rings (organic rings in which the electrons are delocalized).
In optics, a prism is a transparent optical element with flat, polished surfaces that refract light.
In mathematics, two variables are proportional if there is always a constant ratio between them.
A quasar (also known as a QSO or quasi-stellar object) is an extremely luminous active galactic nucleus (AGN).
The radial velocity of an object with respect to a given point is the rate of change of the distance between the object and the point.
In physics, and in particular as measured by radiometry, radiant energy is the energy of electromagnetic and gravitational radiation.
Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies.
Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light.
In physics, redshift happens when light or other electromagnetic radiation from an object is increased in wavelength, or shifted to the red end of the spectrum.
In astronomy, reflection nebulae are clouds of interstellar dust which might reflect the light of a nearby star or stars.
Robert Wilhelm Eberhard Bunsen (30 March 1811N1 – 16 August 1899) was a German chemist.
Ruby Violet Payne-Scott, BSc(Phys) MSc DipEd(Syd) (28 May 1912 – 25 May 1981) was an Australian pioneer in radiophysics and radio astronomy, and was the first female radio astronomer.
S-type asteroids are asteroids with a spectral type that is indicative of a silicaceous (i.e. stony) mineralogical composition, hence the name.
Sagittarius A or Sgr A is a complex radio source at the center of the Milky Way.
Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter.
Sea interferometry, also known as Sea-cliff interferometry, is a form of radio astronomy that uses radio waves reflected off the sea to produce an interference pattern.
In chemistry, a silicate is any member of a family of anions consisting of silicon and oxygen, usually with the general formula, where 0 ≤ x Silicate anions are often large polymeric molecules with an extense variety of structures, including chains and rings (as in polymeric metasilicate), double chains (as in, and sheets (as in. In geology and astronomy, the term silicate is used to mean silicate minerals, ionic solids with silicate anions; as well as rock types that consist predominantly of such minerals. In that context, the term also includes the non-ionic compound silicon dioxide (silica, quartz), which would correspond to x.
Sodium is a chemical element with symbol Na (from Latin natrium) and atomic number 11.
The Solar SystemCapitalization of the name varies.
In spectroscopy, spectral flux density is the quantity that describes the rate at which energy is transferred by electromagnetic radiation through a real or virtual surface, per unit surface area and per unit wavelength.
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies.
A spectrograph is an instrument that separates light into a frequency spectrum and records the signal using a camera.
A spectrometer is a scientific instrument used to separate and measure spectral components of a physical phenomenon.
In chemistry, spectrophotometry is the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength.
Spectroscopy is the study of the interaction between matter and electromagnetic radiation.
In quantum mechanics and particle physics, spin is an intrinsic form of angular momentum carried by elementary particles, composite particles (hadrons), and atomic nuclei.
Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work The Realm of the Nebulae(pp. 124–151) and, as such, form part of the Hubble sequence.
A star is type of astronomical object consisting of a luminous spheroid of plasma held together by its own gravity.
A star system or stellar system is a small number of stars that orbit each other, bound by gravitational attraction.
The Stefan–Boltzmann law describes the power radiated from a black body in terms of its temperature.
In astronomy, stellar classification is the classification of stars based on their spectral characteristics.
The Sun is the star at the center of the Solar System.
A supernova (plural: supernovae or supernovas, abbreviations: SN and SNe) is a transient astronomical event that occurs during the last stellar evolutionary stages of a star's life, either a massive star or a white dwarf, whose destruction is marked by one final, titanic explosion.
Titan is the largest moon of Saturn.
Titanium is a chemical element with symbol Ti and atomic number 22.
Ultraviolet (UV) is electromagnetic radiation with a wavelength from 10 nm to 400 nm, shorter than that of visible light but longer than X-rays.
Venus is the second planet from the Sun, orbiting it every 224.7 Earth days.
Vesto Melvin Slipher (November 11, 1875 – November 8, 1969) was an American astronomer who performed the first measurements of radial velocities for galaxies, providing the empirical basis for the expansion of the universe.
The Virgo Cluster is a cluster of galaxies whose center is 53.8 ± 0.3 Mly (16.5 ± 0.1 Mpc) away in the constellation Virgo.
The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye.
Walter Robert Wilhelm Grotrian (21 April 1890 in Aachen; † 3 March 1954 in Potsdam) was a German astronomer and astrophysicist.
In physics, interference is a phenomenon in which two waves superpose to form a resultant wave of greater, lower, or the same amplitude.
A white dwarf, also called a degenerate dwarf, is a stellar core remnant composed mostly of electron-degenerate matter.
Wien's displacement law states that the black body radiation curve for different temperatures peaks at a wavelength inversely proportional to the temperature.
Wilhelm Carl Werner Otto Fritz Franz Wien (13 January 1864 – 30 August 1928) was a German physicist who, in 1893, used theories about heat and electromagnetism to deduce Wien's displacement law, which calculates the emission of a blackbody at any temperature from the emission at any one reference temperature.
William Harkness (December 17, 1837 – February 28, 1903) was an astronomer, born at Ecclefechan, Scotland, a son of James (1803–78) and Jane (née Wield) Harkness.
Sir William Huggins (7 February 1824 – 12 May 1910) was an English astronomer best known for his pioneering work in astronomical spectroscopy together with his wife Margaret Lindsay Huggins.
X-rays make up X-radiation, a form of electromagnetic radiation.
The X-group of asteroids collects together several types with similar spectra, but probably quite different compositions.
Astronomical Spectroscopy, Astrospectroscopy, Radio spectroscopy, Solar spectroscopist, Solar spectroscopy, Spectroscopic astronomy, Spectroscopy (astronomy), Spectroscopy of the Sun, Stellar Specta, Stellar spectography, Stellar spectra, Stellar spectroscopy, Stellar spectrum.