User:Marshallsumter/Radiation astronomy1/Luminescences

Def. any "emission of light that cannot be attributed merely to the temperature of the emitting body" is called luminescence.

Alpha quartzes
Def. "a continuous framework [tectosilicate] of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall [chemical] formula [of] SiO2 ... [of] trigonal trapezohedral class 3 2", usually with some substitutional or interstitial impurities, is called α-quartz.

When the concentration of interstitial or substitutional impurities becomes sufficient to change the space group of a mineral such as α-quartz, the result is another mineral. When the physical conditions are sufficient to change the solid space group of α-quartz without changing the chemical composition or formula, another mineral results.

"Shocked quartz is associated with two high pressure polymorphs of silicon dioxide: coesite and stishovite. These polymorphs have a crystal structure different from standard quartz. Again, this structure can only be formed by intense pressure, but moderate temperatures. High temperatures would anneal the quartz back to its standard form."

"Short-rived bottle-green or blue luminescence colours with zones of non-luminescing bands are very common in authigenic quartz overgrowths, fracture fillings or idiomorphic vein crystals. Dark brown, short-lived yellow or pink colours are often found in quartz replacing sulphate minerals. Quartz from tectonically active regions commonly exhibits a brown luminescence colour. A red luminescence colour is typical for quartz crystallized close to a volcanic dyke or sill."

Referring to the image on the right: "Lake County experienced incredible volcanic activity. The heat melted the quartz but temperatures and pressures were just right so it was not destroyed. Rather, the melted quartz was carried along with the lava flows."

Charoites
Charoite is a rare silicate mineral, first described in 1978 and named for the Chara River. It has been reported only from the Aldan Shield, Sakha Republic, Siberia, Russia. It is found where a syenite of the Murunskii Massif has intruded into and altered limestone deposits producing a potassium feldspar metasomatite.

Charoite occurs in association with tinaksite and canasite.

Corundums
Ruby is one of the traditional cardinal gems, together with amethyst, sapphire, emerald, and diamond.

Using UV light is one of the most effective ways to determine the authenticity of a ruby. Under the influence of ultraviolet light with a wavelength of 365 nanometers, ruby gives a uniform red fluorescence. This applies to both transparent and any other types of rubies. Artificial stones emit orange light in this UV spectrum.

Diopsides
Diopside is a precursor of chrysotile (white asbestos) by hydrothermal alteration and magmatic differentiation; it can react with hydrous solutions of magnesium and chlorine to yield chrysotile by heating at 600 °C for three days. Some vermiculite deposits, most notably those in Libby, Montana, are contaminated with chrysotile (as well as other forms of asbestos) that formed from diopside.

Much chromian diopside from the Green River Basin localities and several of the State Line Kimberlites have been gem in character.

Fluorites
The small amount of heat generated by being held in the hand has been reported as enough to induce luminiscence, though this may be the result of experimental error.

As of it was still not known which if any of these impurities imparts to chlorophane the luminescent properties that distinguish it from fluorite.

Some samples of chlorophane, particularly those exposed to high temperatures, will only luminesce once or will do so with only weakened intensity over time.

A very bright luminescence can be achieved at between 200 C and 300 C, and mineralogists once believed that it would glow indefinitely at temperatures of just 30 C, meaning that when exposed on the ground in warmer climates, the mineral would glow year-round.

The unusual properties of chlorophane have been attributed to samarium, terbium, dysprosium, gadolinium, ytterbium, and yttrium; none of these rare earth elements, however, has been consistently found in all chlorophane specimens.

Nephrites
Nephrite is an inosilicate variety of the calcium, magnesium, and iron-rich amphibole minerals tremolite or actinolite (aggregates of which also make up one form of asbestos), with the chemical formula of Ca2(Mg,Fe)5Si8O22(OH)2.

Quartzes
Red "thermoluminescence (RTL) emission from quartz, as a dosimeter for baked sediments and volcanic deposits, [from] older (i.e., >1 Ma), quartz-bearing known age volcanic deposits [can use as standards] independently-dated silicic volcanic deposits from New Zealand, ranging in age from 300 ka through to 1.6 Ma."

The typical quartz UV thermoluminescent curve consists at least of two peaks at ca. 280°C and 325°C. The area under the 325°C peak is equivalent to a dose of ca. 320 Gy. The relation between dose and luminescence signal is sample depended.

Sodalites
"Sodalite is a rich royal blue mineral ... massive sodalite samples are opaque, crystals are usually transparent to translucent. ... Occurring typically in massive form, sodalite is found as vein fillings in plutonic igneous rocks such as nepheline syenites."

"The following features and examples imply why stress of tectosilicate lattices can be linked to the luminescence emission at 340 nm: (i) natural metastable hatch-cross texture in exsolved Na/K microcline at 300 K, (ii) radiation damaged areas in natural quartz, (iii) natural quartz with large amounts of silicon substitution with aluminum and alkali ions, (iv) artificial porous silica with OH groups adsorbed to the surfaces, (v) sodalite feldspathoid in which many tetrahedral silicon Si4+ are substituted with intrinsic aluminum–chlorine defects, (vi) [ionoluminescence] IL at low temperature of all tectosilicate analyzed samples enhanced the 340 nm peak."

Sodalite has the formula Na4Al3Si3O12Cl.

Fluorescences
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation. However, when the absorbed electromagnetic radiation is intense, it is possible for one electron to absorb two photons; this two-photon absorption can lead to emission of radiation having a shorter wavelength than the absorbed radiation. The emitted radiation may also be of the same wavelength as the absorbed radiation, termed "resonance fluorescence".

Iridescences
Def. the "condition or state of producing a display of lustrous, rainbowlike exhibition colors like those of the rainbow; a prismatic play of color" is called iridescence.

Phosphorescences
Def. the "emission of light [for a period of time after the source of excitation is taken away] without any perceptible heat" is called phosphorescence.

Polarization
Rod-shaped rare earth-doped nanocrystal phosphors exhibit peculiarly polarized luminescence spectra, from which the crystal orientation in 3D can be measured. This is employed to observe rotation of nano-objects and their synchronized assembly. Spectroscopy becomes an eye to see dynamics on the nanoscale.

Protons
"The total number of admixed protons in [seven percent of a normal solar mass] is of the order of 4 X 1050."

"The photoluminescence, arising from excitation of the nitrogen-vacancy defect centers created by proton-beam irradiation and thermal annealing, closely resembles the extended red emission (ERE) bands observed in reflection nebulae and planetary nebulae. The central wavelength of the emission is 700 nm".

Optically stimulated luminescences
In quartz a short daylight exposure in the range of 1–100 seconds before burial is sufficient to effectively “reset” the OSL dating clock.

Single Quartz OSL ages can be determined typically from 100 to 350,000 years BP, and can be reliable when suitable methods are used and proper checks are done.

Optical dating using Optically stimulated luminescence (OSL) has been used on sediments.

In multiple-aliquot testing, a number of grains of sand are stimulated at the same time and the resulting luminescence signature is averaged. The problem with this technique is that the operator does not know the individual figures that are being averaged, and so if there are partially prebleached grains in the sample it can give an exaggerated age.

In contrast to the multiple-aliquot method, the Single-aliquot-regenerative-dose (SAR) method tests the burial ages of individual grains of sand which are then plotted. Mixed deposits can be identified and taken into consideration when determining the age

Surfaces
Surfaces made of granite, basalt and sandstone, such as carved rock from ancient monuments and artifacts in ancient buildings has dated using luminescence in several cases of various monuments.

Visuals
Def. "the natural medium emanating from the sun and other very hot sources (now recognised as electromagnetic radiation with a wavelength of 400-750 nm), within which vision is possible" is called light.

Def. "to shine light on something" is called illuminate.

Def. "emitting light" is called luminous.

Def.


 * 1) "the state of being luminous or a luminous object",
 * 2) "the ratio of luminous flux to radiant flux at the same wavelength",
 * 3) "the rate at which a star radiates energy in all directions"

is called luminosity.

Reds
"Diamond nanocrystals (size 100 nm) emit bright luminescence at 600–800 nm when exposed to green and yellow photons."

Infrared stimulated luminescences
Infrared stimulated luminescence (IRSL) dating of potassium feldspars has been used.

Feldspar IRSL techniques have the potential to extend the datable range out to a million years as feldspars typically have significantly higher dose saturation levels than quartz, though issues regarding anomalous fading will need to be dealt with first. Ages can be obtained outside this these ranges, but they should be regarded with caution. The uncertainty of an OSL date is typically 5-10% of the age of the sample.

Cathodoluminescences
The inelastic scattering of the primary electrons in the crystal leads to the emission of secondary electrons, Auger electrons and X-rays, which in turn can scatter as well, which leads to up to 103 secondary electrons per incident electron.

These secondary electrons can excite valence electrons into the conduction band when they have a kinetic energy about three times the band gap energy of the material $$(E_{kin}\approx 3 E_g)$$.

The primary advantages to the electron microscope based technique is its spatial resolution, where the attainable resolution is on the order of a few ten nanometers, while in a (scanning) transmission electron microscope, nanometer-sized features can be resolved.

An optical cathodoluminescence microscope benefits from its ability to show actual visible color features directly through the eyepiece, where more recently developed systems try to combine both an optical and an electron microscope to take advantage of both these techniques.

Cathodoluminescence performed in electron microscopes is also being used to study surface plasmon resonances in metallic nanoparticles. Surface plasmons in metal nanoparticles can absorb and emit light, though the process is different from that in semiconductors. Similarly, cathodoluminescence has been exploited as a probe to map the local density of states of planar dielectric photonic crystals and nanostructured photonic materials.

Electroluminescences
Condensed noble gases, most notably liquid xenon and liquid argon, are excellent radiation detection media. They can produce two signatures for each particle interaction: a fast flash of light (scintillation) and the local release of charge (ionisation). In two-phase xenon – so called since it involves liquid and gas phases in equilibrium – the scintillation light produced by an interaction in the liquid is detected directly with photomultiplier tubes; the ionisation electrons released at the interaction site are drifted up to the liquid surface under an external electric field, and subsequently emitted into a thin layer of xenon vapour. Once in the gas, they generate a second, larger pulse of light (electroluminescence or proportional scintillation), which is detected by the same array of photomultipliers. These systems are also known as xenon 'emission detectors'.

Thermoluminescences
Thermoluminescence (TL) research was focused on heated pottery and ceramics, burnt flints, baked hearth sediments, oven stones from burnt mounds and other heated objects.

TL can be used to date unheated sediments.

TL dating of light-sensitive traps in geological sediments of both terrestrial and marine origin became more widespread.

Heliums
The "formation of the luminescent subordinate HeI lines by the absorption of continuum radiation from a source in the lines of the main HeI series in the expanding Universe [may occur]."

At "some moment of time, corresponding to the redshift z0, a burst of superequilibrium blackbody radiation with a temperature T + ∆T occurs. This radiation is partially absorbed at different z < z0 in the lines of the main HeI series and then converted into the radiation of subordinate lines."

"For different z [...], the quantum yield for the subordinate lines of para- and orthohelium - the number of photons emitted in the subordinate line, per one initial excited atom and line profiles are calculated."

Accounting "for forbidden transitions significantly changes the luminescence intensity in para- and orthohelium".

For "sufficiently large ∆T/T, the luminescent lines can be very noticeable in the spectrum of blackbody background radiation."

Alloys
"The broad, 60 < FWHM < 100 nm, featureless luminescence band known as extended red emission (ERE) is seen in such diverse dusty astrophysical environments as reflection nebulae17, planetary nebulae3, HII regions (Orion)12, a Nova11, Galactic cirrus14, a dark nebula7, Galaxies8,6 and the diffuse interstellar medium (ISM)4. The band is confined between 540-950 nm, but the wavelength of peak emission varies from environment to environment, even within a given object. ... the wavelength of peak emission is longer and the efficiency of the luminescence is lower, the harder and denser the illuminating radiation field is13. These general characteristics of ERE constrain the photoluminescence (PL) band and efficiency for laboratory analysis of dust analog materials."

"The PL efficiencies measured for HAC and Si-HAC alloys are consistent with dust estimates for reflection nebulae and planetary nebulae, but exhibit substantial photoluminescence below 540 nm which is not observed in astrophysical environments."

"Optical constants measured at normal incidence for iron (Bolotin et al., 1969) and for iron-nickel alloys (Sasovskaya and Noskov, 1974) also predict a red-sloped spectrum."

Bioluminescences
Def. "the emission of light by a living organism (such as a firefly)" is called bioluminescence.

Bioluminescence is a form of chemiluminescence where light energy is released by a chemical reaction that involves a light-emitting pigment, the luciferin, and a luciferase, the enzyme component.

Because of the diversity of luciferin/luciferase combinations, there are very few commonalities in the chemical mechanism, where the only unifying mechanism is the role of molecular oxygen, which provides chemical energy.

The firefly luciferin/luciferase reaction requires magnesium, adenosine triphosphate (ATP) and produces CO2, adenosine monophosphate (AMP) and pyrophosphate (PP) as waste products, where other cofactors may be required, such as calcium (Ca2+) for the photoprotein aequorin, or magnesium (Mg2+) ions and ATP for the firefly luciferase. Generically, this reaction can be described as:


 * Luciferin + O2Oxyluciferin + light energy.

When seen from below by a predator as in the image on the left, the bioluminescence helps to match the squid's brightness and colour to the sea surface above.

In many animals of the deep sea, including several squid species, bacterial bioluminescence is used for camouflage by counter-illumination, in which the animal matches the overhead environmental light as seen from below. In these animals, photoreceptors control the illumination to match the brightness of the background. These light organs are usually separate from the tissue containing the bioluminescent bacteria. However, in one species, Euprymna scolopes, the bacteria are an integral component of the animal's light organ.

Neanderthals or Homo heidelbergensis
In "Greece [optically stimulated luminescence (OSL) dating] has produced dates of over 400,000 years old. The sampling itself took place by moonlight… as exposure to the sun would ruin the process, having initially studied in detail the stratigraphy".

Boreal transition
The Blytt-Sernander stage: Boreal lasted from 9 ka to 7.5 ka.

Evidence, c. 6200 BC, of farmers from the Middle East reaching the Danube and moving into Romania and Serbia.

The domestication of pigs in eastern Europe is believed to have begun c. 6800 BC, where these pigs may have been descended from European wild boar or more probably were introduced by farmers migrating from the Middle East.

At "least two of the giant “wheels” [in the image at center] from Wadi Al Qattafi and the Wisad Pools, in the Black Desert of Jordan are at least 8,500 years old [dated using optically stimulated luminescence (OSL)] – making them older then the famous Nazca Lines in Peru by about 6,000 years."

Devensian glaciations
"The results of paired terrestrial cosmogenic nuclide analyses / constrain the timing of this extensive glaciation and provide, for the first time, an age for the exposure of Lundy granite following deglaciation. The results from nine paired samples yield / exposure ages of 31.4-48.8 ka and 31.7-60.0 ka ."

"Bowen et al. (2002) used to provide exposure ages for glacial landforms around Ireland and demonstrated that the most extensive phase of glaciation in many areas dates from the Early Devensian."

" A exposure age of 19.8 ka from an upturned boulder on the Isles of Scilly (McCarroll et al., 2010), at the southernmost limit of an Irish Sea Ice Stream (ISIS), may suggest a Late Devensian age close to the global Last Glacial Maximum (LGM; 21 ka) a date which is supported by radiocarbon and thermoluminescence dates (Wintle, 1981; Scourse, 1991, 2006)."

"Furthermore, this age for the glacial and related sediments on the Isles of Scilly is independently supported by ice rafted debris of Celtic Sea sources in continental margin cores from the Goban Spur that date to Heinrich Event 2 (Scourse et al., 2000, 2009; Haapaniemi et al., 2010). This pulse may well represent the Celtic Sea advance to Scilly during the LGM, as discussed in Scourse and Furze (2001)."

Weichselian glaciations
"Recent stratigraphical achievements and long time established chronologies exist for the Late Weichselian, i.e. 10-25 ka BP. During this period Denmark experienced the complex Main-Weichselian glaciation from 25 to about 14 ka BP (Jylland stade, Houmark-Nielsen 1989) followed by the Late Glacial climatic amelioration including the interstadial Bølling-Allerød oscillation (13-11 ka BP), finally leading to the interglacial conditions that characterize the Holocene (Hansen 1965)."

"The Weichselian of Europe covers the interval from the end of MIS-5e (c. 119 kyr BP) to the start of the Holocene at c. 11.5 kyr BP and corresponds to the isotope stages 5d to 2. Much of the Weichselian chronology is relative only, determined by stratigraphic relationships of successive glacial and interglacial deposits. Radiocarbon ages for the younger interval and Thermo-Luminescence (TL), Optically Stimulated Luminescence (OSL) and Electron Spin Resonance (ESR) dates for the earlier period are used where available although reliable results remain few. We assume here, therefore, that the Russian􏰀European succession of major glacials and interglacials follows the oscillations of the global sea-level curve of Lambeck & Chappell (2001). The start of stadials is defined by the onset of a sea-level fall and the end is defined by the midpoint between successive lowstands and highstands, in recognition of the lag in icesheet and sea-level response to warming. The Early Weichselian spans the interval from c. 118 kyr BP to c. 80 kyr BP and corresponds to the two stadials MIS-5d and 5b and the two interstadials MIS-5c and 5a. The Middle Weichselian corresponds to the isotope stages MIS-4 and MIS-3 spanning the interval from c. 80 kyr BP to c. 32 kyr BP [...]. As more information becomes available, the interstadials 5c and 5a reveal a more complex structure and each may consist of two or three relative highstands (Potter et al. 2004), implying that ice margins were not constant during these intervals, [...]."

"The early Middle Weichselian is assumed to correspond to the period 80-􏰀62kyr BP and to MIS-4. During this interval, average sea levels reached lower values than during the Early Weichselian and ice extent can be expected to have been substantial. But, as the global sea-level oscillations in this interval are also large, substantial ice-volume fluctuations can be anticipated across northern Eurasia within this stage."

"The last substantial ice movement over arctic Russia is the retreat at the end of MIS-4 back to the Kara Sea and eventually back to the arctic islands such that after c. 55 kyr the major land areas were and remained essentially ice-free. The Scandinavian ice sheet, however, continued to fluctuate throughout Stage 3, with at least two periods of extensive ice-free conditions corresponding to the Bø interstadial (at c. 52 kyr BP) when the ice retreated to northern Sweden, and the Ålesund interstadial (at c. 35 kyr), when much of Scandinavia may have been ice-free. At least one major advance (the Jæren-Klintholm-Skjonghelleren advance at c. 45-40 kyr BP) occurred in between these two interstadials (Olsen 1997; Larsen et al. 2000; Arnold et al. 2003; Houmark-Nielsen & Kjær 2003). The LGM and post-LGM ice model adopted is that previously constrained by rebound data across Scandinavia and northern Europe (Lambeck et al. 1998b; Lambeck & Purcell 2003)."

Western Europe
"During the Allerød Chronozone, 11,800 to 11,000 years ago, western Europe approached the present day environmental and climatic situation, after having suffered the last glacial maximum some 20,000 to 18,000 years ago. However, the climatic deterioration 11,000 years ago led to nearly fully glacial conditions on this continent for some few hundreds of years during the Younger Dryas. This change is completely out of phase with the Milankovitch (orbital) forcing as this is understood today, and therefore its cause is of major interest."

"During the Allerød a branch of the North Atlantic Current entered the Norwegian Sea (Ruddiman and Mclntyre, 1973, 1981)."

"Recent stratigraphical achievements and long time established chronologies exist for the Late Weichselian, i.e. 10-25 ka BP. During this period Denmark experienced the complex Main-Weichselian glaciation from 25 to about 14 ka BP (Jylland stade, Houmark-Nielsen 1989) followed by the Late Glacial climatic amelioration including the interstadial Bølling-Allerød oscillation (13-11 ka BP), finally leading to the interglacial conditions that characterize the Holocene (Hansen 1965)."

The "large, but so far largely ignored eruption of the Laacher See-volcano, located in present-day western Germany and dated to 12,920 BP, had a dramatic impact on forager demography all along the northern periphery of Late Glacial settlement and precipitated archaeologically visible cultural change. In Southern Scandinavia, these changes took the form of technological simplification, the loss of bow-and-arrow technology, and coincident with these changes, the emergence of the regionally distinct Bromme culture. Groups in north-eastern Europe appear to have responded to the eruption in similar ways, but on the British Isles and in the Thuringian Basin populations contracted or relocated, leaving these areas largely depopulated already before the onset of the Younger Dryas/GS-1 cooling."

"Lommel (1) is in northern Belgium, near the border with the Netherlands. At 12.94 ka (2), this site was a large late Glacial sand ridge covered by open forest at the northern edge of a marsh. More than 50 archaeological sites in this area indicate frequent visits by the late Magdalenians, hunter-gatherers who were contemporaries of the Clovis culture in North America. Throughout the Bölling-Allerod, eolian sediments known as the Coversands blanketed the Lommel area. Then, just before the Younger Dryas began, a thin layer of bleached sand was deposited and, in turn, was covered by the dark layer marked "YDB" above. That stratum is called the Usselo Horizon and is composed of fine to medium quartz sands rich in charcoal. The dark Usselo Horizon is stratigraphically equivalent to the YDB layer and contains a similar assemblage of impact markers (magnetic grains, magnetic microspherules, iridium, charcoal, and glass-like carbon). The magnetic grains have a high concentration of Ir (117 ppb), which is the highest value measured for all sites yet analyzed. On the other hand, YDB bulk sediment analyses reveal Ir values below the detection limit of 0.5 ppb, suggesting that the Ir carrier is in the magnetic grain fraction. The abundant charcoal in this black layer suggests widespread biomass burning. A similar layer of charcoal, found at many other sites in Europe, including the Netherlands (3), Great Britain, France, Germany, Denmark, and Poland (4), also dates to the onset of the Younger Dryas (12.9 ka) and, hence, correlates with the YDB layer in North America."

Usselo is the type site for the 'Usselo Soil', the 'Usselo horizon' or 'Usselo layer', a distinctive and widespread Weichselian (Lateglacial) buried soil, paleosol, found within Lateglacial eolian sediments known as 'cover sands' in the Netherlands, western Germany, and western Denmark; classified as either a weakly podzolized Arenosol or as a weakly podzolized Regosol, where numerous radiocarbon dates, optically stimulated luminescence dates, pollen analyses, and archaeological evidence from a number of locations have been interpreted to show that the Usselo Soil formed as the result of pedogenesis during a period of landscape stability during the Allerød oscillation that locally continued into the Younger Dryas stadial as a marker bed.

The abundant charcoal, which is found in the Usselo Soil, and contemporaneous Lateglacial paleosols and organic sediments across Europe, may have been created by wildfires caused by a large bolide impact, based upon the reported occurrence of alleged extraterrestrial impact indicators and hypothetical correlations with Clovis-age organic beds in North America. However, the contemporaneous nature of the Usselo Soil with Clovis-age organic beds in North America, the presence of impact indicators within it, and the impact origin of the charcoal may only be apparent.

In the second image down on the right, the soil profile is from the "Postdüne" catchment area of ​​the river Finow near Eberswalde (Agrarmuseum Wandlitz, Brandenburg). The upper brown layer is called "Finowboden". During the 700-year period of the Alleröd, 12,500 years ago, the summers were almost as warm as they are today. Pine-birch forests expanded, with their closed vegetation covering the earth's surface. This created one of the first post glacial soils. Until the 1990s, this type of bottoming was known only from Western and Eastern Europe.

Meteorites
"The Raman spectra of some [interplanetary dust particle] IDPs also show red photoluminescence that is similar to the excess red emission seen in some astronomical objects and that has also been attributed to [polycyclic aromatic hydrocarbons] PAH s and hydrogenated amorphous carbon. Moreover, a part of the carbonaceous phase in IDPs and meteorites contains deuterium to hydrogen ratios that are greater than those for terrestrial samples."

Earth
In the International Space Station image at right, you can "see green and yellow airglow paralleling the Earth’s horizon line (or limb) before it is overwhelmed by the light of the rising Sun. Airglow is the emission of light by atoms and molecules in the upper atmosphere after they are excited by ultraviolet radiation. ... Astronaut photograph ISS030-E-015491 was acquired on December 22, 2011, with a Nikon digital camera, and is provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Center."

Airglow (also called nightglow) is the very weak emission of light by a planetary atmosphere. In the case of Earth's atmosphere, this optical phenomenon causes the night sky to never be completely dark (even after the effects of starlight and diffused sunlight from the far side are removed).

Airglow is caused by various processes in the upper atmosphere, such as the recombination of ions which were photoionized by the sun during the day, luminescence caused by cosmic rays striking the upper atmosphere, and chemiluminescence caused mainly by oxygen and nitrogen reacting with hydroxyl ions at heights of a few hundred kilometers. It is not noticeable during the daytime because of the scattered light from the Sun.

On the left, the plane of the Milky Way — rippled with dust, gas and stars — elegantly stretches above three of the four Unit Telescopes of the Very Large Telescope (VLT) in this unusual fulldome fish-eye perspective from ESO's Paranal Observatory in northern Chile. The red and green radiance scattering the sky is a luminescence known as airglow.

Auroral ovals
An auroral oval is a permanent region of luminescence 15 to 25 degrees in latitude from the magnetic poles and 5 to 20 degrees wide.

"This series of near-simultaneous auroras [on the left] were observed between 11:24 am and 12:10 pm Universal Time (6:24am and 7:10am ET) on October 23, 2002. Observations were made of the northern (left) and southern (right) hemispheres by IMAGE and Polar satellites, respectively. White dots indicate the geographic poles. Analysis of the spacecraft images showed how the auroras shift depending on the "tilt" of the Earth's magnetic field toward the sun and conditions in the solar wind. The "12" at the top indicates noon (the direction toward the sun), and "0" at the bottom indicates midnight, (the direction away from the sun). Likewise, the "6" indicates dawn or morning side of the Earth, while "18" indicates dusk or evening side of the Earth, thus placing the auroras on a 24 hour clock face."

"Looking at the auroras from space, they look like almost circular bands of light around the North and South Poles."

"From spacecraft observations made in October, 2002, scientists noticed that these circular bands of aurora shift in opposite directions to each other depending on the orientation of the sun's magnetic field, which travels toward the Earth with the solar wind flow. They also noted that the auroras shift in opposite directions to each other depending on how far the Earth's northern magnetic pole is leaning toward the sun."

"What was most surprising was that both the northern and southern auroral ovals were leaning toward the dawn (morning) side of the Earth for this event."

"This is the first analysis to use simultaneous observations of the whole aurora in both the northern and southern hemispheres to track their locations."

Mars
"[L]uminescence dating techniques [may] provide absolute age determinations of eolian sediments on the surface of Mars, including those incorporated in the martian polar ice caps. Fundamental thermally and optically stimulated luminescence properties of bulk samples of JSC Mars-1 soil simulant [have been studied]. The radiation-induced luminescence signals (both thermoluminescence, TL, and optically stimulated luminescence, OSL) from JSC Mars-1 are found to have a wide dynamic dose–response range, with the luminescence increasing linearly to the highest doses used (936 Gy), following irradiation with 90Sr/90Y beta particles."

Ultraviolet stars
Stellar class O stars have surface temperatures high enough that most of their luminescence is in the ultraviolet. The peaks of their Planckian spectra start at about 38,000 K and increase in temperature, or in wavelength start at about 79 nm and decrease in the ultraviolet.

Archaeology
"Some 540,000 years ago, an ancient ancestor of modern humans took a shark tooth and carefully carved a geometric engraving [shown close-up in the image on the right] on a mollusk shell."

"The engraving -- the oldest piece of art ever found by at least 300,000 years -- as well as a shell tool were found at a site in what is now Java, Indonesia."

The discovery was made while "studying a fossil freshwater mussel shell assemblage from a site called Trinil in Java. The mussel shells originally were excavated by Eugène Dubois in the 1890s, but have been stored in the Dubois collection of the Naturalis museum in Leiden, The Netherlands. Sediment within the shells enabled them to be dated using both isotopic and luminescence methods."

"Clay deposition in the Piauí River floodplain around 436 ± 51.5 ka occurred during a warmer period of the [Yarmouthian interglaciation] Aftonian interglaciation, corresponding to isotope stage 12 (Ericson and Wollin, 1968)."

"The extinctions and earliest known first occurrences of the 26 extant and 8 extinct cyst taxa in the three samples (with a minimum 430,000 yr BP Yarmouthian age) corroborate a likely assemblages with a maximum age of Illinoian (ca. 220,000-430,000 yr BP) in Unit I."

Yarmouthian spans 420,000-500,000 yr BP.

A "fossil freshwater shell assemblage from the Hauptknochenschicht (‘main bone layer’) of Trinil (Java, Indonesia), the type locality of Homo erectus discovered by Eugène Dubois in 1891 (refs 2 and 3) [in] the Dubois collection (in the Naturalis museum, Leiden, The Netherlands) [there is evidence] for freshwater shellfish consumption by hominins, one unambiguous shell tool, and a shell with a geometric engraving. We dated sediment contained in the shells with 40Ar/39Ar and luminescence dating methods, obtaining a maximum age of 0.54 ± 0.10 million years and a minimum age of 0.43 ± 0.05 million years."

Luminescent light backgrounds
"The Rotating Drum Spectrometer (RDS) experiment is planned to be placed onboard Ruscosmos Multipurpose Laboratory Module ”NAUKA” on the International Space Station (ISS) [...]. The experiment is designed to measure X-ray spectra of Solar flares using Bragg reflection from flat crystals. Additionally to the reflection of X-ray photons crystals produce luminescent light. In order to separate those physical effects during real experiment data analysis, computer simulations are necessary."

The eight crystals in order around the drum are ADP oriented with [101] surface out, Si [111], Quartz [10-11], Si [220], Si [111], KAP [001], Qu [10-10] and Si [400], where ammonium dihydrogen phosphate is (ADP), potassium acid phthalate (KAP), and Quartz (Qu).

"The RDS instrument is dedicated to measure detailed soft X-ray solar spectra with a great temporal resolution (up to 0.1 s). The instrument will reconstruct the photon spectra based on the Bragg reflections from crystals, such designs are known to have high luminescence background signal. [Luminescent] background simulations using Geant4 toolkit [compared] with the expected Bragg reflected photon fluxes. [The] luminescent background is significantly lower for four of the used crystals than the observed solar continuum emission and is comparable with it for the rest of crystals. The luminescent background can be even lower in the observed data by applying narrower energy filters during data analysis [...]."

Scintillation detectors
A scintillator is a material, which exhibits scintillation—the property of luminescence when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate, i.e., reemit the absorbed energy in the form of light. Here, "particle" refers to "ionizing radiation" and can refer either to charged particulate radiation, such as electrons and heavy charged particles, or to uncharged radiation, such as photons and neutrons, provided that they have enough energy to induce ionization.

A scintillation detector or scintillation counter is obtained when a scintillator is coupled to an electronic light sensor such as a photomultiplier tube (PMT) or a photodiode. PMTs absorb the light emitted by the scintillator and reemit it in the form of electrons via the photoelectric effect. The subsequent multiplication of those electrons (sometimes called photo-electrons) results in an electrical pulse which can then be analyzed and yield meaningful information about the particle that originally struck the scintillator.

On the right is a "close-up view of an engineering model of SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals), one the instruments aboard NASA's Perseverance Mars rover. Located on the end of the rover's robotic arm, this instrument features an auto-focusing camera (pictured) that shoots black-and-white images used by SHERLOC's color camera, called WATSON (Wide Angle Topographic Sensor for Operations and eNgineering), to zero in on rock textures. SHERLOC also has a laser, which aims for the dead center of rock surfaces depicted in WATSON's images."

"The laser uses a technique called Raman spectroscopy to detect minerals in microscopic rock features; that data is then superimposed on WATSON's images. These mineral maps help scientists determine which rock samples Perseverance should drill so that they can be sealed in metal tubes and left on the Martian surface for a future mission to return to Earth."

On the left is a test image by SHERLOC (Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals), an instrument aboard NASA's Perseverance rover, each color represents a different mineral detected on a rock's surface.

Second down on the right is a diagram that shows components of the investigations payload for NASA's Mars 2020 rover mission:
 * 1) Mastcam-Z, an advanced camera system with panoramic and stereoscopic imaging capability and the ability to zoom. The instrument also will determine mineralogy of the Martian surface and assist with rover operations. The principal investigator is James Bell, Arizona State University in Tempe.
 * 2) SuperCam, an instrument that can provide imaging, chemical composition analysis, and mineralogy. The instrument will also be able to detect the presence of organic compounds in rocks and regolith from a distance. The principal investigator is Roger Wiens, Los Alamos National Laboratory, Los Alamos, New Mexico. This instrument also has a significant contribution from the Centre National d'Etudes Spatiales, Institut de Recherche en Astrophysique et Planétologie (CNES/IRAP) France.
 * 3) Planetary Instrument for X-ray Lithochemistry (PIXL), an X-ray fluorescence spectrometer that will also contain an imager with high resolution to determine the fine-scale elemental composition of Martian surface materials. PIXL will provide capabilities that permit more detailed detection and analysis of chemical elements than ever before. The principal investigator is Abigail Allwood, NASA's Jet Propulsion Laboratory, Pasadena, California.
 * 4) Scanning Habitable Environments with Raman & Luminescence for Organics and Chemicals (SHERLOC), a spectrometer that will provide fine-scale imaging and uses an ultraviolet (UV) laser to determine fine-scale mineralogy and detect organic compounds. SHERLOC will be the first UV Raman spectrometer to fly to the surface of Mars and will provide complementary measurements with other instruments in the payload. SHERLOC includes a high-resolution color camera for microscopic imaging of Mars' surface. The principal investigator is Luther Beegle, JPL.
 * 5) The Mars Oxygen ISRU Experiment (MOXIE), an exploration technology investigation that will produce oxygen from Martian atmospheric carbon dioxide. The principal investigator is Michael Hecht, Massachusetts Institute of Technology, Cambridge, Massachusetts.
 * 6) Mars Environmental Dynamics Analyzer (MEDA), a set of sensors that will provide measurements of temperature, wind speed and direction, pressure, relative humidity and dust size and shape. The principal investigator is Jose Rodriguez-Manfredi, Centro de Astrobiologia, Instituto Nacional de Tecnica Aeroespacial, Spain.
 * 7) The Radar Imager for Mars' Subsurface Experiment (RIMFAX), a ground-penetrating radar that will provide centimeter-scale resolution of the geologic structure of the subsurface. The principal investigator is Svein-Erik Hamran, the Norwegian Defence Research Establishment, Norway.