Bok Globule
In 1947, Bart Bok suggested that the small dark globules of interstellar gas and dust were undergoing collapse on their way to forming new stars. In recent years, a great deal of evidence supporting this proposal has been found.
Globule
A dense, spherical cloud of dust that absorbs radiation (see Bok globule).
Glueball ...
GLOBULE
A globule is an interstellar cloud of dust and hydrogen gas that contracts and undergoes gravitational collapse to form a star.
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Bok Globules
Small, dark clouds only about 1 light year in diameter that contain 10-1000 solar masses of gas and dust. Believed to be related to star formation.
Bow Shock ...
Bok globule: Small, dark cloud only about 1 ly in diameter that contains 10 to 1000 solar masses of gas and dust; believed to be related to star formation.
Bok globule
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Bok globules in H II region IC 2944.
The actual birth of stars within H II regions is hidden from us by the dense clouds of gas and dust which surround the nascent stars.
These globules, first identified by astronomer A.D. Thackeray in 1950, float in this very active star-forming region.
Recent observations at radio wavelengths of a gas cloud known as Bok Globule B335 have produced images of material collapsing onto a newly born star (only about 150,000 years old).
A synthetic radioactive element first detected by bombarding a bismuth target with chromium nuclei. Only a small number of atoms have ever been produced.
Symbol: Bh; p.n. 107; most stable isotope 262Bh (half life 0.1s). [DC99]
Bok Globule ...
Main article: Bok globule
Isolated gravitationally bound small molecular clouds with masses less than a few hundred times the mass of the sun are called Bok globules.
EVAPORATING GAS GLOBULES (EGGs) - Small dense clumps of gas and dust (sometimes with newborn stars inside) part of a larger molecular cloud that are being overrun by a photoevaporating ionization front.
Found that some Bok globules contain protostars
Cataloged thousands of hot, dense cores within clouds of gas and dust which could be newly forming stars
Cataloged over 12,000 variable stars, the largest collection known to date ...
The key pieces of evidence they presented for primitive Martian life were as follows: (1) Bacteria on Earth can produce structures similar to the globules shown in the inset.
Lunar Soils contain glassy globules not commonly found on the Earth. These are probably formed from the heat and pressure generated by meteor impacts.
Orange-colored Carbonate Mineral Globules
This photograph shows orange-colored carbonate mineral globules found in a meteorite, called ALH84001, believed to have once been a part of Mars.
A primordial protoplasmic globule
So the calculation goes that the probability of forming a given 300 amino acid long protein (say an enzyme like carboxypeptidase) randomly is (1/20)300 or 1 chance in 2.
This photograph shows orange-colored carbonate mineral globules found in a meteorite, called ALH84001, believed to have once been a part of Mars. These carbonate minerals in the meteorite are believed to have been formed on Mars more than 3.
As the cloud collapses, individual conglomerations of dense dust and gas form what are known as Bok globules. These can contain up to 50 solar masses of material.
"M16, the Eagle Nebula shows newborn stars emerging from "eggs" - not the barnyard variety - but rather, dense, compact pockets of interstellar gas called evaporating gaseous globules (EGGs).
The cometary globule, CG 4
AAT 78. Part of the Vela supernova remnant
AAT 81. ESO 166-21, a faint planetary nebula
AAT 84. The Pencil nebula, NGC 2736
AAT 107. NGC 2437-38, planetary nebula in open cluster ...
Bart Jan Bok
1906-1983
Dutch
suggested that small dark globules of interstellar gas and dusk (now called Bok globules) are collapsing to form new stars ...
6 billion years ago, some kind of liquid flowed through the rock and deposited rounded globules of carbonate minerals.
Finally, in the lower part of the image, a finger of gas pokes out from the cloud, pointing directly at the central star powering the Trifid. This is an example of an evaporating gaseous globule, and at the tip of the finger, ...
The columns are called EGG's (Evaporating Gaseous Globules) because the ultraviolet light boils off some of the hydrogen gas (H2), shaping the nebula in a process called photoevaporation. The biggest column is about 1 light-year tall.
Large dark nebulae that can contain over a million solar masses of material and extend over 200 parsecs are known as giant molecular clouds. The smallest ones, called Bok globules, ...
The anthelia (from the Greek duet, opposite, and i Xcos, the sun) are coloured red on the inside, the outside being generally colourless owing to the continued overlapping of many spectra. The diameter increases with the size of the globules making ...
toward the center, providing the protostar with heat and a weak infra-red glow -- heat is defined as particle motion -- and rotation (think of an ice skater pulling in her arms as she goes into a spin). (Protostars can be detected in Bok Globules.) ...
Many astronomers believe that these bodies, called globules, are in the process of condensation and are the initial stages in the birth of stars. Planetary nebulae appear through the telescope as small disks with well-defined boundaries.
emulsions (NASA Thesaurus) Suspensions of fine particle or globules of one or more liquids in another liquid. enamel (NASA SP-7, 1965) A thin ceramic coating, usually of high glass content, applied to a substrate, generally a metal.
 See also: Light, Dust, Earth, Star, Sun
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