PPV_hd169142
... Fig. 5:NICMOS camera 2 (FOV = 19.2” x 19.3”, scale: ~ 75.8 mas/pixel) direct and coronagraphic imagery of HD 169142A and its nearby environment was obtained in a single HST orbit on 2005 April 30. Each observation set consisted of (a) two short F171M (1.71 mm) target acquisition images, (b) three de ...
... Fig. 5:NICMOS camera 2 (FOV = 19.2” x 19.3”, scale: ~ 75.8 mas/pixel) direct and coronagraphic imagery of HD 169142A and its nearby environment was obtained in a single HST orbit on 2005 April 30. Each observation set consisted of (a) two short F171M (1.71 mm) target acquisition images, (b) three de ...
SkyWatcher - Boise Astronomical Society
... that comets are more dynamic than anyone realized. The missions found that dust and gas burst from a comet's nucleus every few days or weeks—fleeting phenomena that would have gone unnoticed if it weren't for the constant and nearby observations. But space missions are expensive, so for three upcomi ...
... that comets are more dynamic than anyone realized. The missions found that dust and gas burst from a comet's nucleus every few days or weeks—fleeting phenomena that would have gone unnoticed if it weren't for the constant and nearby observations. But space missions are expensive, so for three upcomi ...
Chapter 15 Observational Evidence for Black Holes
... The first strong case found, and most famous stellar black hole candidate, is called Cygnus X-1 (the first X-ray source discovered in the constellation Cygnus). 1. In the early 1970s an X-ray source was discovered in Cygnus and designated Cygnus X-1. 2. In 1972, a radio source was found in the same ...
... The first strong case found, and most famous stellar black hole candidate, is called Cygnus X-1 (the first X-ray source discovered in the constellation Cygnus). 1. In the early 1970s an X-ray source was discovered in Cygnus and designated Cygnus X-1. 2. In 1972, a radio source was found in the same ...
Good Vibrations and Stellar Pulsations - Physics
... heat and that the leakage is made good by a steady supply of heat. The ordinary method of setting the engine going is to vary the supply of heat, increasing it during compression and diminishing it during expansion. That is the first alternative we considered. But it would come to the same thing if ...
... heat and that the leakage is made good by a steady supply of heat. The ordinary method of setting the engine going is to vary the supply of heat, increasing it during compression and diminishing it during expansion. That is the first alternative we considered. But it would come to the same thing if ...
Stellar Luminosities
... Luminosity of the Sun • Another way to look at this is to measure the amount of energy in sunlight falling on a unit surface area, then multiply by the number of unit areas on the surface of a sphere with a radius of 1 `AU’. • One measure of the Sun’s apparent brightness is the `Solar Constant’: 1. ...
... Luminosity of the Sun • Another way to look at this is to measure the amount of energy in sunlight falling on a unit surface area, then multiply by the number of unit areas on the surface of a sphere with a radius of 1 `AU’. • One measure of the Sun’s apparent brightness is the `Solar Constant’: 1. ...
The Life Cycle of A Star
... dwarfs are stable because the inward pull of gravity is balanced by the electrons in the core of the star repulsing each other. With no fuel left to burn, the hot star radiates its remaining heat into the coldness of space for many billions of years. In the end, it will just sit in space as a cold d ...
... dwarfs are stable because the inward pull of gravity is balanced by the electrons in the core of the star repulsing each other. With no fuel left to burn, the hot star radiates its remaining heat into the coldness of space for many billions of years. In the end, it will just sit in space as a cold d ...
ppt
... positions as a function of epoch over all plates on which a star appears. New proper motions are calculated, and the process is iterated until it converges to the final proper motion values. Proper-motion uncertainties are determined from the scatter about the best-fit line. Typically, the reference ...
... positions as a function of epoch over all plates on which a star appears. New proper motions are calculated, and the process is iterated until it converges to the final proper motion values. Proper-motion uncertainties are determined from the scatter about the best-fit line. Typically, the reference ...
the summary
... afterglows fade very rapidly in time: after a day, the brightness has dropped by about a factor hundred compared to half an hour after the initial trigger. In order to obtain good-quality data, or sometimes to be able to observe the optical counterpart at all, it is crucial to follow up on a gamma-r ...
... afterglows fade very rapidly in time: after a day, the brightness has dropped by about a factor hundred compared to half an hour after the initial trigger. In order to obtain good-quality data, or sometimes to be able to observe the optical counterpart at all, it is crucial to follow up on a gamma-r ...
Chapter 13: Interstellar Matter and Star Formation
... (ii) Lines caused by a stellar atmosphere will have a different Doppler shift than those caused by the interstellar gas. (iii) Interstellar gas will generally be much cooler than the gas of the stellar atmosphere. (c) In 1951, Purcell and Ewen used a specially built radio telescope to detect the 21- ...
... (ii) Lines caused by a stellar atmosphere will have a different Doppler shift than those caused by the interstellar gas. (iii) Interstellar gas will generally be much cooler than the gas of the stellar atmosphere. (c) In 1951, Purcell and Ewen used a specially built radio telescope to detect the 21- ...
Review: How does a star`s mass determine its life story?
... object of the same mass. However, you’d see strange effects for an object falling toward the black hole: – Time would seem to run slowly for the object – Its light would be increasingly redshifted as it approached the black hole. – The object would never quite reach the event horizon, but it would s ...
... object of the same mass. However, you’d see strange effects for an object falling toward the black hole: – Time would seem to run slowly for the object – Its light would be increasingly redshifted as it approached the black hole. – The object would never quite reach the event horizon, but it would s ...
EXOPLANETS The search for planets beyond our solar system
... the Sun; and 47 Ursae Majoris b, a cooler gas giant orbiting further away from its parent star. The first multiple-planet system containing three Jupiter-like planets orbiting at different inclinations (unlike our coplanar solar system) was also identified orbiting the star Upsilon Andromedae, and i ...
... the Sun; and 47 Ursae Majoris b, a cooler gas giant orbiting further away from its parent star. The first multiple-planet system containing three Jupiter-like planets orbiting at different inclinations (unlike our coplanar solar system) was also identified orbiting the star Upsilon Andromedae, and i ...
what are stars made of?
... Gravity brings global clusters together Global clusters are large groups of stars that are held together by their own gravity. These groups of stars are very old and often have millions of members. ...
... Gravity brings global clusters together Global clusters are large groups of stars that are held together by their own gravity. These groups of stars are very old and often have millions of members. ...
MESSIER - EarthLink
... His first own deep sky discovery of globular cluster M3, cataloged on May 3, probably causes him to undertake a systematical search for nebulous objects, leading to the observation and recording of the objects M3-M40, many of which were own discoveries, but several from old catalogs. Messier was mad ...
... His first own deep sky discovery of globular cluster M3, cataloged on May 3, probably causes him to undertake a systematical search for nebulous objects, leading to the observation and recording of the objects M3-M40, many of which were own discoveries, but several from old catalogs. Messier was mad ...
The Death of Stars
... 2. A planetary nebula is a. the expelled outer envelope of a medium mass star. b. produced by a supernova explosion. c. produced by a nova explosion. d. a nebula within which planets are forming. e. a cloud of hot gas surround a planet 3. The Chandrasekhar limit tells us that a. accretion disks can ...
... 2. A planetary nebula is a. the expelled outer envelope of a medium mass star. b. produced by a supernova explosion. c. produced by a nova explosion. d. a nebula within which planets are forming. e. a cloud of hot gas surround a planet 3. The Chandrasekhar limit tells us that a. accretion disks can ...
CHP 13
... 2. A planetary nebula is a. the expelled outer envelope of a medium mass star. b. produced by a supernova explosion. c. produced by a nova explosion. d. a nebula within which planets are forming. e. a cloud of hot gas surround a planet 3. The Chandrasekhar limit tells us that a. accretion disks can ...
... 2. A planetary nebula is a. the expelled outer envelope of a medium mass star. b. produced by a supernova explosion. c. produced by a nova explosion. d. a nebula within which planets are forming. e. a cloud of hot gas surround a planet 3. The Chandrasekhar limit tells us that a. accretion disks can ...
Phys 214. Planets and Life
... How do we classify stars? Because all stars are born with basically the same composition (98% H & He), the physics that determines the star characteristics is straightforward. During the H burning phase, the star’s surface temperature (or spectral type) and total luminosity is determined almost ent ...
... How do we classify stars? Because all stars are born with basically the same composition (98% H & He), the physics that determines the star characteristics is straightforward. During the H burning phase, the star’s surface temperature (or spectral type) and total luminosity is determined almost ent ...
7.4 Evolution on the Main-Sequence Main-sequence (m
... and to maintain the pressure, the density has to increase through core contraction which in turn causes the temperature to increase. As a result, increases and this causes an increase in L. This effect follows from eqn. (7.19, 7.20) relating T and L to µ. For the Sun, L has increased by 30% from Z ...
... and to maintain the pressure, the density has to increase through core contraction which in turn causes the temperature to increase. As a result, increases and this causes an increase in L. This effect follows from eqn. (7.19, 7.20) relating T and L to µ. For the Sun, L has increased by 30% from Z ...
Stars, Galaxies, and the Universe Section 1 Section 1
... from Earth, is caused by the movement of Earth. • The stars seem as though they are moving counterclockwise around a central star called Polaris, the North Star. Polaris is almost directly above the North Pole, and thus the star does not appear to move much. • Earth’s revolution around the sun cause ...
... from Earth, is caused by the movement of Earth. • The stars seem as though they are moving counterclockwise around a central star called Polaris, the North Star. Polaris is almost directly above the North Pole, and thus the star does not appear to move much. • Earth’s revolution around the sun cause ...
Presentation - University of Idaho
... The presence of a massive object exerts a force that causes all objects to deviate from this path by the same amount ...
... The presence of a massive object exerts a force that causes all objects to deviate from this path by the same amount ...
Interstellar medium, birth and life of stars
... The most massive pre–main-sequence stars take the shortest time to become main-sequence stars (O and B stars). In the final stages of pre–main-sequence contraction, when hydrogen fusion is about to begin in the core, the pre–main-sequence star may undergo vigorous chromospheric activity that eje ...
... The most massive pre–main-sequence stars take the shortest time to become main-sequence stars (O and B stars). In the final stages of pre–main-sequence contraction, when hydrogen fusion is about to begin in the core, the pre–main-sequence star may undergo vigorous chromospheric activity that eje ...
Cygnus (constellation)
Cygnus /ˈsɪɡnəs/ is a northern constellation lying on the plane of the Milky Way, deriving its name from the Latinized Greek word for swan. The swan is one of the most recognizable constellations of the northern summer and autumn, it features a prominent asterism known as the Northern Cross (in contrast to the Southern Cross). Cygnus was among the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations.Cygnus contains Deneb, one of the brightest stars in the night sky and one corner of the Summer Triangle, as well as some notable X-ray sources and the giant stellar association of Cygnus OB2. One of the stars of this association, NML Cygni, is one of the largest stars currently known. The constellation is also home to Cygnus X-1, a distant X-ray binary containing a supergiant and unseen massive companion that was the first object widely held to be a black hole. Many star systems in Cygnus have known planets as a result of the Kepler Mission observing one patch of the sky, the patch is the area around Cygnus. In addition, most of the eastern part of Cygnus is dominated by the Hercules–Corona Borealis Great Wall, a giant galaxy filament that is the largest known structure in the observable universe; covering most of the northern sky.