DTU_9e_ch13
... A pulsar is a rapidly rotating neutron star with a powerful magnetic field that makes it a source of periodic radio and other electromagnetic pulses. Energy pours out of the polar regions of the neutron star in intense beams that sweep across the sky. ...
... A pulsar is a rapidly rotating neutron star with a powerful magnetic field that makes it a source of periodic radio and other electromagnetic pulses. Energy pours out of the polar regions of the neutron star in intense beams that sweep across the sky. ...
Initial performance of the aspect system on the Chandra
... For the Chandra aspect determination problem, Kalman filtering is used to combine ACA star centroids and gyro data to determine the motion of the ACA and the gyro bias rate. A Kalman filter is the “optimal” method for estimating the state of a dynamical system given a time series of noisy measuremen ...
... For the Chandra aspect determination problem, Kalman filtering is used to combine ACA star centroids and gyro data to determine the motion of the ACA and the gyro bias rate. A Kalman filter is the “optimal” method for estimating the state of a dynamical system given a time series of noisy measuremen ...
Neutron Stars PowerPoint
... – Thought to have solid crust of ordinary neutrons – Thought to have fluid interior of degenerate neutrons ...
... – Thought to have solid crust of ordinary neutrons – Thought to have fluid interior of degenerate neutrons ...
second grade - Math/Science Nucleus
... The Universe is a vast space of unknown dimensions. The Milky Way is our address in the Universe. Our Sun is only one small component amongst the other billions of stars in our galaxy, the Milky Way. The Solar System is a group of 9 planets that revolve around the Sun. We see objects in the night sk ...
... The Universe is a vast space of unknown dimensions. The Milky Way is our address in the Universe. Our Sun is only one small component amongst the other billions of stars in our galaxy, the Milky Way. The Solar System is a group of 9 planets that revolve around the Sun. We see objects in the night sk ...
The Primordial Abundance of $^ 6$ Li and $^ 9$ be
... production of 6 Li and 7 Li (in roughly equally proportions) by cosmic rays. Thus, the observations are consistent with SBBN, provided that HD 84937 is a subgiant. The parallax of HD 84937 is 0.0277′′ ± 0.0065′′ (van Altena, Lee & Hoffleit 1994). If HD 84937 is a sub-giant, then the models predict a ...
... production of 6 Li and 7 Li (in roughly equally proportions) by cosmic rays. Thus, the observations are consistent with SBBN, provided that HD 84937 is a subgiant. The parallax of HD 84937 is 0.0277′′ ± 0.0065′′ (van Altena, Lee & Hoffleit 1994). If HD 84937 is a sub-giant, then the models predict a ...
Part 2 of Our Lecture
... • SEDs of low-mass stars in NGC 7160 (about 10 Myr) (according to the same procedures followed for Tr 37) only 1 sample shows indications of active accretion (CTTS). – black dotted line : similar spectral type derived from Kenyon & Hartmann (1995) – magenta dashed line : the median disk emission i ...
... • SEDs of low-mass stars in NGC 7160 (about 10 Myr) (according to the same procedures followed for Tr 37) only 1 sample shows indications of active accretion (CTTS). – black dotted line : similar spectral type derived from Kenyon & Hartmann (1995) – magenta dashed line : the median disk emission i ...
CHP 15
... Radio maps of our galaxy show spiral arms because the a. arms have high Doppler shifts. b. gas in the spiral arms is hot enough to emit photons. c. dust in spiral arms is more dense than it is between the spiral arms. d. gas in spiral arms is more dense than it is between the spiral arms. e. stars i ...
... Radio maps of our galaxy show spiral arms because the a. arms have high Doppler shifts. b. gas in the spiral arms is hot enough to emit photons. c. dust in spiral arms is more dense than it is between the spiral arms. d. gas in spiral arms is more dense than it is between the spiral arms. e. stars i ...
Spectroscopic variability of two Oe stars
... which include a ratio LLbol ∼ 10−6 , i.e. a factor 10 higher than for normal OB stars but at least an order of magnitude lower than for Be high-mass X-ray binaries, variations on timescales from minutes to months, and an X-ray spectrum that is dominated by a very hot plasma with kT ≥ 10 keV. The ori ...
... which include a ratio LLbol ∼ 10−6 , i.e. a factor 10 higher than for normal OB stars but at least an order of magnitude lower than for Be high-mass X-ray binaries, variations on timescales from minutes to months, and an X-ray spectrum that is dominated by a very hot plasma with kT ≥ 10 keV. The ori ...
Stars, Constellations, and the Celestial Sphere
... of a plane tangent to Earth at O with the celestial sphere. Everything that the observer can see is above the tangent plane (represented by the green line in the figure). The angle between the celestial equator (yellow line) and the horizon (green line) is equal to 90° minus the latitude of the obse ...
... of a plane tangent to Earth at O with the celestial sphere. Everything that the observer can see is above the tangent plane (represented by the green line in the figure). The angle between the celestial equator (yellow line) and the horizon (green line) is equal to 90° minus the latitude of the obse ...
Life Cycle of the Stars
... the evolution of stars somewhat more and somewhat less massive than the Sun. The shape of the paths is similar, but they wind up in different places on the main sequence. ...
... the evolution of stars somewhat more and somewhat less massive than the Sun. The shape of the paths is similar, but they wind up in different places on the main sequence. ...
Epsilon Aurigae – CCD Photometry Using a Small Telescope
... Use View | Zoom In to see more closely what is being included in the aperture and the annulus. Use the Single Star Photometry Tool to examine several of your images, taken through your various filters. It’s best to settle on a set of three radii that will be fixed across ALL of your images for the e ...
... Use View | Zoom In to see more closely what is being included in the aperture and the annulus. Use the Single Star Photometry Tool to examine several of your images, taken through your various filters. It’s best to settle on a set of three radii that will be fixed across ALL of your images for the e ...
offprint
... of He 6678 assuming nrp, while an (ad-hoc) model based on variable local linewidth (e.g. by non-uniform micro-turbulence across the stellar surface) could reproduce the He 6678 at least in principle. But Maintz et al. (2000), exploring a larger parameter space than considered by Balona et al. (1 ...
... of He 6678 assuming nrp, while an (ad-hoc) model based on variable local linewidth (e.g. by non-uniform micro-turbulence across the stellar surface) could reproduce the He 6678 at least in principle. But Maintz et al. (2000), exploring a larger parameter space than considered by Balona et al. (1 ...
Astronomy Astrophysics − Astrophysical parameters of the peculiar X-ray transient
... We used the interstellar lines in the spectrum of HD 306414 to study the radial velocity distribution of interstellar material along its line of sight. We calculated the velocity scale with respect to the local standard of rest (LSR) by assuming that the Sun’s motion with respect to the LSR correspo ...
... We used the interstellar lines in the spectrum of HD 306414 to study the radial velocity distribution of interstellar material along its line of sight. We calculated the velocity scale with respect to the local standard of rest (LSR) by assuming that the Sun’s motion with respect to the LSR correspo ...
PHYS3380_110215_bw - The University of Texas at Dallas
... •In stars more than 1.3 times the mass of the Sun, the nuclear fusion of hydrogen into helium occurs via CNO cycle instead of the proton-proton chain. The CNO process is very temperature sensitive, so the core is very hot but the temperature falls off rapidly. Therefore, the core region forms a conv ...
... •In stars more than 1.3 times the mass of the Sun, the nuclear fusion of hydrogen into helium occurs via CNO cycle instead of the proton-proton chain. The CNO process is very temperature sensitive, so the core is very hot but the temperature falls off rapidly. Therefore, the core region forms a conv ...
The HARPS search for southern extra-solar planets
... Bonfils et al. (2007) used variations of these indices to unveil a 35 days rotation period for Gl 674, later confirmed by a photometric campaign, but those of Gl 581 do not measurably vary. The low rotational velocity which we measure for Gl 581 (v sin i < 1 kms−1 ) would require large spots to prod ...
... Bonfils et al. (2007) used variations of these indices to unveil a 35 days rotation period for Gl 674, later confirmed by a photometric campaign, but those of Gl 581 do not measurably vary. The low rotational velocity which we measure for Gl 581 (v sin i < 1 kms−1 ) would require large spots to prod ...
Skymax-180 Review by Sky At Night Magazine
... I call the scope my ‘planet killer’! The best single upgrade I have made to the telescope was to add a Moonlite focuser. This has made a great telescope into an amazing one, as I take high-resolution lunar images and the focuser makes this a breeze to achieve, critical focus is important. After 30 y ...
... I call the scope my ‘planet killer’! The best single upgrade I have made to the telescope was to add a Moonlite focuser. This has made a great telescope into an amazing one, as I take high-resolution lunar images and the focuser makes this a breeze to achieve, critical focus is important. After 30 y ...
doc - Pocket Stars
... Orbital paths of inner planets and sun. Time Animation. Black, white, and red star chart colors for normal, bright, and night viewing conditions, respectively. Chart can be rotated to any of the 16 compass points and also flipped along the North - South axis. Chart can be "live, realtime", or static ...
... Orbital paths of inner planets and sun. Time Animation. Black, white, and red star chart colors for normal, bright, and night viewing conditions, respectively. Chart can be rotated to any of the 16 compass points and also flipped along the North - South axis. Chart can be "live, realtime", or static ...
The star Epsilon UMa, or more commonly known as Alioth
... way to remember these classes in order is by remembering that “Only Bored Astronomers Find Gratification Knowing Mnemonics”. Alioth’s spectral type is A in which for these stars the color of the light emitted ranges from a very light blue to white and the approximate surface temperature ranges from ...
... way to remember these classes in order is by remembering that “Only Bored Astronomers Find Gratification Knowing Mnemonics”. Alioth’s spectral type is A in which for these stars the color of the light emitted ranges from a very light blue to white and the approximate surface temperature ranges from ...
Student Activity: Using a Mariner`s Astrolabe
... students to observe specific celestial objects, e.g., Jupiter, Betelgeuse, other stars of Orion in the winter. To really detect the motion or Earth, students need to record nightly observations of altitude and azimuth for the celestial objects being investigated at the same time each evening for ...
... students to observe specific celestial objects, e.g., Jupiter, Betelgeuse, other stars of Orion in the winter. To really detect the motion or Earth, students need to record nightly observations of altitude and azimuth for the celestial objects being investigated at the same time each evening for ...
docx - STAO
... students to observe specific celestial objects, e.g., Jupiter, Betelgeuse, other stars of Orion in the winter. To really detect the motion or Earth, students need to record nightly observations of altitude and azimuth for the celestial objects being investigated at the same time each evening for ...
... students to observe specific celestial objects, e.g., Jupiter, Betelgeuse, other stars of Orion in the winter. To really detect the motion or Earth, students need to record nightly observations of altitude and azimuth for the celestial objects being investigated at the same time each evening for ...
Hipparcos
Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial objects on the sky. This permitted the accurate determination of proper motions and parallaxes of stars, allowing a determination of their distance and tangential velocity. When combined with radial-velocity measurements from spectroscopy, this pinpointed all six quantities needed to determine the motion of stars. The resulting Hipparcos Catalogue, a high-precision catalogue of more than 118,200 stars, was published in 1997. The lower-precision Tycho Catalogue of more than a million stars was published at the same time, while the enhanced Tycho-2 Catalogue of 2.5 million stars was published in 2000. Hipparcos ' follow-up mission, Gaia, was launched in 2013.The word ""Hipparcos"" is an acronym for High precision parallax collecting satellite and also a reference to the ancient Greek astronomer Hipparchus of Nicaea, who is noted for applications of trigonometry to astronomy and his discovery of the precession of the equinoxes.