The professional project VEGA/CHARA and participation of ASPA
... emission line Hα of different participants and from different publications. The current time span is: 1975 to 2009 Fig.4 (below) The second contribution is the measurement of the radial velocity of Hα mainly performed by my colleague Roland Bücke (Hamburg). This figure shows the current state of his ...
... emission line Hα of different participants and from different publications. The current time span is: 1975 to 2009 Fig.4 (below) The second contribution is the measurement of the radial velocity of Hα mainly performed by my colleague Roland Bücke (Hamburg). This figure shows the current state of his ...
LISTENING FOR THE HUM OF NEUTRON STARS IN THE CENTER
... created by rapidly rotating neutron stars with, for example, a small deviation from perfect axial symmetry. The waves are extremely weak but since they last over much longer time scales than the observation time. This allows us to integrate over long data stretches to dig out the weak signal from th ...
... created by rapidly rotating neutron stars with, for example, a small deviation from perfect axial symmetry. The waves are extremely weak but since they last over much longer time scales than the observation time. This allows us to integrate over long data stretches to dig out the weak signal from th ...
The Milky Way
... • Out to solar distance (about 8 kpc) the mass is about 1 x 1011 M (mostly stars) • Out to ~15 kpc, (the visible radius) a good estimate for the mass is nearly 4 x 1011 M ...
... • Out to solar distance (about 8 kpc) the mass is about 1 x 1011 M (mostly stars) • Out to ~15 kpc, (the visible radius) a good estimate for the mass is nearly 4 x 1011 M ...
Review 3 (11-18-10)
... size of Earth. Atoms stop further collapse. M less than 1.4 solar masses • Neutron Stars: even denser, about mass of Sun in size of Orlando. Neutrons stop further collapse. M between 1.4 and 3 solar masses. Some neutron stars can be detected as pulsars • Black Holes: M more than 3 solar masses. Noth ...
... size of Earth. Atoms stop further collapse. M less than 1.4 solar masses • Neutron Stars: even denser, about mass of Sun in size of Orlando. Neutrons stop further collapse. M between 1.4 and 3 solar masses. Some neutron stars can be detected as pulsars • Black Holes: M more than 3 solar masses. Noth ...
Is Protostellar Jet Spinning? Chin
... is estimated to be ~ 30 yrs. This periodic variation may be due to a solar-type magnetic cycle or a periodic disturbance of an unseen stellar companion orbiting the protostar at ~ 4 AU away with a period of 30 yrs. The averaged two-sided mass-loss rate of the jet is estimated to be (1-3) x10-6 M⊙ yr ...
... is estimated to be ~ 30 yrs. This periodic variation may be due to a solar-type magnetic cycle or a periodic disturbance of an unseen stellar companion orbiting the protostar at ~ 4 AU away with a period of 30 yrs. The averaged two-sided mass-loss rate of the jet is estimated to be (1-3) x10-6 M⊙ yr ...
The Life of the Sun
... all the rest of the stages. So those are relatively short stages in a Star’s life. We refer to the Main Sequence as the majority of the Star’s life and that’s exactly what it is. Then it goes off and does all these really cool things but those happen essentially in the blink of a Cosmic eye. Once th ...
... all the rest of the stages. So those are relatively short stages in a Star’s life. We refer to the Main Sequence as the majority of the Star’s life and that’s exactly what it is. Then it goes off and does all these really cool things but those happen essentially in the blink of a Cosmic eye. Once th ...
Searching for RR Lyrae Stars in M15
... an object is how luminous an object is as seen from Earth while the absolute magnitude of an object is what the apparent magnitude would be if the source was located 10 parsecs away from us. The distance modulus helps in determining distances and magnitudes to various objects. This very convenient f ...
... an object is how luminous an object is as seen from Earth while the absolute magnitude of an object is what the apparent magnitude would be if the source was located 10 parsecs away from us. The distance modulus helps in determining distances and magnitudes to various objects. This very convenient f ...
Absolute magnitude of type Ia supernovae
... last stage of a star’s evolution. Since its brightness temporarily reach to a few hundreds million times of our sun’s, we can find it from fairly far distance. It rarely occurs once in a hundred years at a galaxy, but there are many galaxies in the Universe, therefore by observing everywhere, a supe ...
... last stage of a star’s evolution. Since its brightness temporarily reach to a few hundreds million times of our sun’s, we can find it from fairly far distance. It rarely occurs once in a hundred years at a galaxy, but there are many galaxies in the Universe, therefore by observing everywhere, a supe ...
Slides from the fourth lecture
... Swift, we began imaging the GRB field 8 minutes after the burst and continued for the following 8 days. No convincing optical/infrared candidate afterglow or supernova was found for the object. We present a re-analysis of the XRT afterglow and find an absolute position that is ~4" to the west of the ...
... Swift, we began imaging the GRB field 8 minutes after the burst and continued for the following 8 days. No convincing optical/infrared candidate afterglow or supernova was found for the object. We present a re-analysis of the XRT afterglow and find an absolute position that is ~4" to the west of the ...
High Precision Parallax Collecting Satellite
... Many a night I saw the Pleiads, rising thro’ the mellow shade Glitter like a swarm of fireflies, tangled in a silver braid. ...
... Many a night I saw the Pleiads, rising thro’ the mellow shade Glitter like a swarm of fireflies, tangled in a silver braid. ...
New Double Stars from Asteroidal Occultations, 1971 - 2008
... 6. Dunham, D. W., 1979, “Duplicity of both (18) Melpomene and SAO 114159 discovered during occul- and hence of the asteroid. This has been the main motation”, Occultation Newsletter, vol. 2, pp. 12 – 16. tivation for observing asteroidal occultations. The greatest difficulty with observing asteroida ...
... 6. Dunham, D. W., 1979, “Duplicity of both (18) Melpomene and SAO 114159 discovered during occul- and hence of the asteroid. This has been the main motation”, Occultation Newsletter, vol. 2, pp. 12 – 16. tivation for observing asteroidal occultations. The greatest difficulty with observing asteroida ...
Lecture03-ASTA01
... • If you watch the Moon for just an hour, you can see it move eastward against the background of stars by slightly more than its own apparent diameter. • Each night when you look at the Moon, you will see it is roughly half the width of a zodiac constellation—about 13 degrees—to the east of its loca ...
... • If you watch the Moon for just an hour, you can see it move eastward against the background of stars by slightly more than its own apparent diameter. • Each night when you look at the Moon, you will see it is roughly half the width of a zodiac constellation—about 13 degrees—to the east of its loca ...
Black Holes & Quasars—18 Nov • Black hole • Quasar Ast 207 F2009
... The semi major axis of the orbit is 1000 AU. Show how to find the mass of Sgr A. Give the numerical answer for the mass. (It is easiest to express the mass in solar mass, rather than in kg.) What is the key big idea needed to figuring out the mass from the ...
... The semi major axis of the orbit is 1000 AU. Show how to find the mass of Sgr A. Give the numerical answer for the mass. (It is easiest to express the mass in solar mass, rather than in kg.) What is the key big idea needed to figuring out the mass from the ...
poster
... The emission from young stellar objects (YSOs) in the mid-IR is dominated by the inner rim of their circumstellar disks. We present an IR-monitoring survey in the direction of the Lynds 1688 (L1688) star forming region over four visibility windows spanning 1.6 years using the Spitzer space telescope ...
... The emission from young stellar objects (YSOs) in the mid-IR is dominated by the inner rim of their circumstellar disks. We present an IR-monitoring survey in the direction of the Lynds 1688 (L1688) star forming region over four visibility windows spanning 1.6 years using the Spitzer space telescope ...
OUR SOLAR SYSTEM
... Add in Vesta, Pallas, and Hygiea, the next three largest asteroids, and half the belt’s mass is accounted for. The main belt starts at 2.06 AU, where objects make four orbits around the Sun in the time it takes Jupiter to make one. Astronomers call this a 4:1 orbital resonance. Whenever an asteroid’ ...
... Add in Vesta, Pallas, and Hygiea, the next three largest asteroids, and half the belt’s mass is accounted for. The main belt starts at 2.06 AU, where objects make four orbits around the Sun in the time it takes Jupiter to make one. Astronomers call this a 4:1 orbital resonance. Whenever an asteroid’ ...
L87 THE b PICTORIS MOVING GROUP B. ZUCkERMAN AND
... A caveat is that such detections must be of thermal emission from young, warm planets rather than of reflected starlight from old, cold planets, such as Jupiter. At wavelengths near a few microns, thermal emission from a giant planet that is not older than a few tens of millions of years can be hund ...
... A caveat is that such detections must be of thermal emission from young, warm planets rather than of reflected starlight from old, cold planets, such as Jupiter. At wavelengths near a few microns, thermal emission from a giant planet that is not older than a few tens of millions of years can be hund ...
Ursa Minor
Ursa Minor (Latin: ""Smaller She-Bear"", contrasting with Ursa Major), also known as the Little Bear, is a constellation in the northern sky. Like the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle, hence the name Little Dipper. It was one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and remains one of the 88 modern constellations. Ursa Minor has traditionally been important for navigation, particularly by mariners, due to Polaris being the North Star.Polaris, the brightest star in the constellation, is a yellow-white supergiant and the brightest Cepheid variable star in the night sky, ranging from apparent magnitude 1.97 to 2.00. Beta Ursae Minoris, also known as Kochab, is an aging star that has swollen and cooled to become an orange giant with an apparent magnitude of 2.08, only slightly fainter than Polaris. Kochab and magnitude 3 Gamma Ursae Minoris have been called the ""guardians of the pole star"". Planets have been detected orbiting four of the stars, including Kochab. The constellation also contains an isolated neutron star—Calvera—and H1504+65, the hottest white dwarf yet discovered with a surface temperature of 200,000 K.