Supernovae Oct 19 − Supernova 1987A
... expelled by giants • Iron was made in massive stars and expelled by supernovae • Heavier elements were made in supernovae & in giants by the R & S processes ...
... expelled by giants • Iron was made in massive stars and expelled by supernovae • Heavier elements were made in supernovae & in giants by the R & S processes ...
46. HKU Astronomers Discover Complex Organic Matter in the
... throughout the Universe. The results suggest that complex organic compounds are not the sole domain of life but can be made naturally by stars. Prof. Sun Kwok and Dr. Yong Zhang of The University of Hong Kong show that an organic substance commonly found throughout the Universe contains a mixture of ...
... throughout the Universe. The results suggest that complex organic compounds are not the sole domain of life but can be made naturally by stars. Prof. Sun Kwok and Dr. Yong Zhang of The University of Hong Kong show that an organic substance commonly found throughout the Universe contains a mixture of ...
Exploration of the Milky Way and Nearby galaxies
... Milky Way have accreted and subsequently destroyed 10s - 100s of small dwarf galaxies in the past 10 Gyr Abundance of RGB stars belonging to Local Group dwarf Galaxies are found to be very different from stars of Milky Way halo, disk, bulge and moving groups (Venn et al. 2004, Navarro et al. 2004) T ...
... Milky Way have accreted and subsequently destroyed 10s - 100s of small dwarf galaxies in the past 10 Gyr Abundance of RGB stars belonging to Local Group dwarf Galaxies are found to be very different from stars of Milky Way halo, disk, bulge and moving groups (Venn et al. 2004, Navarro et al. 2004) T ...
Double Stars in Scorpio`s Claws
... stars that are a rewarding challenge to any astronomer. Some of these are actual double stars (pairs of stars that orbit about each other), others are ‘apparent doubles’ – stars that simply lie along the same line of sight, but are very distant from each other in space. The map below indicates the l ...
... stars that are a rewarding challenge to any astronomer. Some of these are actual double stars (pairs of stars that orbit about each other), others are ‘apparent doubles’ – stars that simply lie along the same line of sight, but are very distant from each other in space. The map below indicates the l ...
Lecture 12: Evolution of the Galaxy
... • Star formation takes place in dense molecular clouds in galactic spiral arms • Cloud mass ~ 1000 M⊙, enough to cause gravitational contraction • As density goes up, cloud fragments into a number of collapsing sub-centres. This process continues, eventually with a typical collapsing mass ~ 1 M⊙ • A ...
... • Star formation takes place in dense molecular clouds in galactic spiral arms • Cloud mass ~ 1000 M⊙, enough to cause gravitational contraction • As density goes up, cloud fragments into a number of collapsing sub-centres. This process continues, eventually with a typical collapsing mass ~ 1 M⊙ • A ...
The supernova of AD1181 – an update
... indices α of ≈0.0 to 0.3 – where flux density S varies with frequency υ as S ∝ υ–α – in contrast to typical spectral indices of 0.4 to 0.6 seen on the majority of SNRs, which are of “shell” type. In the shell remnants the relativistic particle spectrum responsible for the observed radio is thought t ...
... indices α of ≈0.0 to 0.3 – where flux density S varies with frequency υ as S ∝ υ–α – in contrast to typical spectral indices of 0.4 to 0.6 seen on the majority of SNRs, which are of “shell” type. In the shell remnants the relativistic particle spectrum responsible for the observed radio is thought t ...
8.1 Radio Emission from Solar System objects
... from the hot ionized gas. In order to understand from which part of the sun’s atmosphere this emission arises, one needs to understand the main opacity source at radio wavelengths. (The opacity is a measure of how much a wave gets absorbed as it travels through a medium). The main source of opacity ...
... from the hot ionized gas. In order to understand from which part of the sun’s atmosphere this emission arises, one needs to understand the main opacity source at radio wavelengths. (The opacity is a measure of how much a wave gets absorbed as it travels through a medium). The main source of opacity ...
Dynamical models of the nucleus of M31
... relaxation (details depend on age of stars) • vector resonant relaxation conserves semi-major axis and eccentricity but not the direction of orbit normal • preliminary models suggest that some or all of the curious features of the stellar distribution in the Galactic center arise naturally in therma ...
... relaxation (details depend on age of stars) • vector resonant relaxation conserves semi-major axis and eccentricity but not the direction of orbit normal • preliminary models suggest that some or all of the curious features of the stellar distribution in the Galactic center arise naturally in therma ...
NEUTRON STARS AND PULSARS Discovery Were it not for
... mass. At this point the inert iron core of a thousand kilometer radius can no longer resist its own gravity—it collapses in a second to a 10 kilometer very hot proto-neutron star leaving behind the rest of the star which then begins to collapse. But a burst of neutrinos is emitted by the hot neutron ...
... mass. At this point the inert iron core of a thousand kilometer radius can no longer resist its own gravity—it collapses in a second to a 10 kilometer very hot proto-neutron star leaving behind the rest of the star which then begins to collapse. But a burst of neutrinos is emitted by the hot neutron ...
Diapositiva 1
... No evidence of significant angular momentum loss There is no trend on rotation with age (vsin i ~ cte) M < 1.6M or B-V > 0.25-0.3: Stellar activity does not depend on age or rotation Very slow angular momentum loss. Braking time ~ 109yr. ...
... No evidence of significant angular momentum loss There is no trend on rotation with age (vsin i ~ cte) M < 1.6M or B-V > 0.25-0.3: Stellar activity does not depend on age or rotation Very slow angular momentum loss. Braking time ~ 109yr. ...
Chapter 07
... b. The upper layers of a star contain hot low-density gases that produce bright lines at precisely the same wavelengths as the dark lines, thus making them invisible. c. Hot hydrogen and helium gas in the interstellar medium produces bright lines to fill in the dark lines. d. The resolution of many ...
... b. The upper layers of a star contain hot low-density gases that produce bright lines at precisely the same wavelengths as the dark lines, thus making them invisible. c. Hot hydrogen and helium gas in the interstellar medium produces bright lines to fill in the dark lines. d. The resolution of many ...
Name: Astronomy Lab: The Hertzsprung-Russell (H
... distance of the star, he suggested there were differences in luminosity among stars of the same spectral class. That is, some stars were at very great distances (small proper motion) but still visible; therefore, they must be much brighter than other stars of the same spectral class that were nearby ...
... distance of the star, he suggested there were differences in luminosity among stars of the same spectral class. That is, some stars were at very great distances (small proper motion) but still visible; therefore, they must be much brighter than other stars of the same spectral class that were nearby ...
r*=13.6 km MPA1 EOS
... Denis A. Leahy, Sharon M. Morsink and Yi Chou The accreting millisecond pulsar XTE J1807-294 is studied through a pulse-shape modeling analysis. The model includes blackbody and Comptonized emission from the one visible hot spot and makes use of the Oblate Schwarzschild approximation for ray-tracing ...
... Denis A. Leahy, Sharon M. Morsink and Yi Chou The accreting millisecond pulsar XTE J1807-294 is studied through a pulse-shape modeling analysis. The model includes blackbody and Comptonized emission from the one visible hot spot and makes use of the Oblate Schwarzschild approximation for ray-tracing ...
Planisphere Exercise
... located just beneath the brass fastener that holds the star wheel to the frame of the planisphere. As the night progresses, which way do the stars appear to move around the North Star (which is hidden under the brass fastener) – clockwise or counterclockwise? ...
... located just beneath the brass fastener that holds the star wheel to the frame of the planisphere. As the night progresses, which way do the stars appear to move around the North Star (which is hidden under the brass fastener) – clockwise or counterclockwise? ...
Part 2 - Stellar Evolution
... Four stages of star formation 1. Form proto-star core within molecular cloud 2. Core grows from surrounding rotating disk 3. Bipolar flow along rotation axis 4. New star clears away the surrounding nebular material ...
... Four stages of star formation 1. Form proto-star core within molecular cloud 2. Core grows from surrounding rotating disk 3. Bipolar flow along rotation axis 4. New star clears away the surrounding nebular material ...
The Spectra of Stars
... • Color of a star depends on its Temperature Color of a star depends on its Temperature – Red Stars are Cooler – Blue Stars are Hotter ...
... • Color of a star depends on its Temperature Color of a star depends on its Temperature – Red Stars are Cooler – Blue Stars are Hotter ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.