Abstract The Star Formation History of Low Surface Brightness Galaxies
... The star formation histories of low surface brightness galaxies are interesting but
poorly constrained. These objects tend to be rather blue, contradicting the initial
impression that they may simply be faded remnants of higher surface brightness
galaxies whose star formation has finished. Other sce ...
Star Formation in the Milky Way and Nearby Galaxies Further
... The past decade has witnessed an unprecedented stream of new observational information on
star formation on all scales, thanks in no small part to new facilities such as the Galaxy Evolution
Explorer (GALEX), the Spitzer Space Telescope, and the Herschel Space Observatory; the introduction
of powerf ...
An X-Ray, Optical and Infra-red study of High-Mass X
... First and foremost I would like to thank my supervisor, Malcolm Coe, for his continued guidance and support. His drive to obtain and exploit all manner of data has
given me a wealth of information on which to base my thesis and sent me to some
of the world’s most incredible places in the process. I ...
Radio Emission Toward Regions of Massive Star Formation
... convention, stars with enough mass to end their lives as core-collapse supernovae (M∗ ≥ 8.0 M )
are considered ‘high-mass’ stars. High-mass stars have difficulty forming in this fashion, because
the onset of fusion occurs before they reach their final main-sequence mass. This works against
... In the 1940’s, it was found that the supernova event that
resulted in the Crab Nebula was witnessed by Chinese
astronomers in the year 1054.
Radio emission from the Crab nebula was first detected by
Bolton, Stanley and Slee (1949). It is one of the most powerful
radio sources known, with a flux of 1 ...
- National Optical Astronomy Observatory
... limit of the telescope at 5 microns is ~0.8 arcseconds. Spatially sampling at
~0.4 arcseconds would then be about right under good seeing.)
! Input scan parameters (number of steps, number of spectral frames,
integration time, etc.)
! Start the scan sequence and simultaneously begin stepping the tra ...
A Dyson sphere is a hypothetical megastructure that completely encompasses a star and hence captures most or all of its power output. It was first described by Olaf Stapledon in his science fiction novel, ""Star Maker"". The concept was later popularly adopted by Freeman Dyson. Dyson speculated that such structures would be the logical consequence of the long-term survival and escalating energy needs of a technological civilization, and proposed that searching for evidence of the existence of such structures might lead to the detection of advanced intelligent extraterrestrial life. Different types of Dyson spheres correlate with information on the Kardashev scale.Since then, other variant designs involving building an artificial structure or series of structures to encompass a star have been proposed in exploratory engineering or described in science fiction under the name ""Dyson sphere"". These later proposals have not been limited to solar-power stations. Many involve habitation or industrial elements. Most fictional depictions describe a solid shell of matter enclosing a star, which is considered the least plausible variant of the idea (see below). In May 2013, at the Starship Century Symposium in San Diego, Dyson repeated his comments that he wished the concept had not been named after him.