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aamukherjee A Slice of Entropie -
alchymista Alchymista -
crownedrose Fading Like A Dead Star -
expose-the-light Quarks to Quasars -
ikenbot CWL -
abluegirl A Blue Girl -
perscientiamlibertas A Matter of the Most Pleasant Fraternal Confidence
Areas in space which are luminous with the emission spectrum of ionized hydrogen are called H II regions.
They are associated with the presence of massive O-type and B-type stars. Such stars, having surface temperatures in the range 15,000 - 30,000K, have characteristic blackbody radiation curves which peak in the ultraviolet. These stars will often be surrounded by vast clouds of hydrogen gas, and the uv can ionize the hydrogen atoms.
These hydrogen atoms tend to attract electrons and reassemble, with the captured electrons cascading down through the quantum states of the hydrogen atom, emitting characteristic photons of light upon each downward jump. A characteristic visible color from such emission is red light at 656 nm associated with the n=3 to n=2 transition which is called H-alpha.
Depending upon the recession velocity of the nebula, the light will be red-shifted, but many regions like the M16 region show a red glow characteristic of the hydrogen emissions. H II regions are associated with young star clusters, and are useful as a part of astronomical distance measurement.
ikenbot
Hypatia of Alexandria
‘Influential Women of Astronomy’
Image: Hypatia as played in the film Agora by Rachel Weisz
Sixteen hundred years ago, Hypatia became one of the world’s leading scholars in mathematics and astronomy. Hypatia’s legendary knowledge, modesty, and public speaking ability flourished during the era of the Great Library of Alexandria.
Hypatia is credited with contributions to geometry and astrometry, and she is thought instrumental in the development of the sky-measuring astrolabe.
“Reserve your right to think, for even to think wrongly is better than not to think at all,” Hypatia is credited with saying.
“To teach superstitions as truth is a most terrible thing.” — Hypatia of Alexandria
cwnl:
Hypatia of Alexandria
‘Influential Women of Astronomy’
Image: Hypatia as played in the film Agora by Rachel Weisz
Sixteen hundred years ago, Hypatia became one of the world’s leading scholars in mathematics and astronomy. Hypatia’s legendary knowledge, modesty, and public speaking ability flourished during the era of the Great Library of Alexandria.
Hypatia is credited with contributions to geometry and astrometry, and she is thought instrumental in the development of the sky-measuring astrolabe.
“Reserve your right to think, for even to think wrongly is better than not to think at all,” Hypatia is credited with saying.
“To teach superstitions as truth is a most terrible thing.” — Hypatia of Alexandria
