The surface composition of Beta Pictoris
... isolated line, and serving as a measure of line strength. They are denoted less certain if the ‘target’ line is not the dominant contributor to a spectral feature (but is still clearly traceable). The stellar microturbulent velocity ξ was determined as usual by comparing abundances derived from vari ...
... isolated line, and serving as a measure of line strength. They are denoted less certain if the ‘target’ line is not the dominant contributor to a spectral feature (but is still clearly traceable). The stellar microturbulent velocity ξ was determined as usual by comparing abundances derived from vari ...
PowerPoint - Louisiana State University
... • FARNESE ATLAS POSITIONS FROM 125 ± 55 BC Eliminates Ptolemy, Aratus, Eudoxus, the Assyrian, and any contemporary Only Hipparchus is consistent with date ...
... • FARNESE ATLAS POSITIONS FROM 125 ± 55 BC Eliminates Ptolemy, Aratus, Eudoxus, the Assyrian, and any contemporary Only Hipparchus is consistent with date ...
PPT presentation
... To spin up the envelope with a companion, need m/Menvelope > ~ 0.1 Other reservoirs of angular momentum also => low envelope mass is necessary ...
... To spin up the envelope with a companion, need m/Menvelope > ~ 0.1 Other reservoirs of angular momentum also => low envelope mass is necessary ...
Kick velocity
... van den Heuvel 2004, 2007) that among Be/X-ray binaries there is a group of systems with small eccentricities. But they suffered one SN explosion and there was no Roche-lobe overflow. This means that kicks in these systems were low. The same is true for some of NS+NS binaries. The proposed mechanism ...
... van den Heuvel 2004, 2007) that among Be/X-ray binaries there is a group of systems with small eccentricities. But they suffered one SN explosion and there was no Roche-lobe overflow. This means that kicks in these systems were low. The same is true for some of NS+NS binaries. The proposed mechanism ...
The loss of nitrogen-rich atmospheres from Earth-like
... gaseous envelope even if the planet orbits its parent M star within the habitable zone (HZ). However, as shown in Lammer et al. (2007), a high CO2 atmospheric mixing ratio will result in enhanced IR cooling in the thermosphere and inhibits its expansion and therefore leads to reduced non-thermal atm ...
... gaseous envelope even if the planet orbits its parent M star within the habitable zone (HZ). However, as shown in Lammer et al. (2007), a high CO2 atmospheric mixing ratio will result in enhanced IR cooling in the thermosphere and inhibits its expansion and therefore leads to reduced non-thermal atm ...
telling time at night
... Example 3: The Dipper clock reads 1 hour on January 15. January 15 is about 10 1/4 months after March 6. The time is therefore 1 - 2 10 1/4 = 19 1/2 hours = 19 1/2 hours before midnight = 4:30 A.M. (To interpret “19 1/2 hours before midnight,” subtract 19 1/2 from 24 hours.) Instead of considering ...
... Example 3: The Dipper clock reads 1 hour on January 15. January 15 is about 10 1/4 months after March 6. The time is therefore 1 - 2 10 1/4 = 19 1/2 hours = 19 1/2 hours before midnight = 4:30 A.M. (To interpret “19 1/2 hours before midnight,” subtract 19 1/2 from 24 hours.) Instead of considering ...
Slide 1
... “Real” IMF must be steeper than apparent IMF for most clusters. 2. Low-mass stars are forming in the starburst cluster. 3. Correction for effect of segregation still leaves a flat IMF in NGC 3603 ( -0.9), but in the LMC clusters (for 0.7 to 5.0 Mo fits) resulting IMFs are very steep: -1.6 - ...
... “Real” IMF must be steeper than apparent IMF for most clusters. 2. Low-mass stars are forming in the starburst cluster. 3. Correction for effect of segregation still leaves a flat IMF in NGC 3603 ( -0.9), but in the LMC clusters (for 0.7 to 5.0 Mo fits) resulting IMFs are very steep: -1.6 - ...
THE SHAPES OF ATOMIC LINES FROM THE SURFACES OF
... Some 18 neutron stars in LMXBs have spin rates ranging from 200 to 600 Hz (see Lamb & Yu 2005) , much higher than the spin rate of the neutron star in EXO 0748676. Spin rates this high imply surface speeds near the rotational equator of 0.05–0.20c. Atomic lines formed at the surfaces of such rapidl ...
... Some 18 neutron stars in LMXBs have spin rates ranging from 200 to 600 Hz (see Lamb & Yu 2005) , much higher than the spin rate of the neutron star in EXO 0748676. Spin rates this high imply surface speeds near the rotational equator of 0.05–0.20c. Atomic lines formed at the surfaces of such rapidl ...
Lecture Topics 1023
... ASTR 1023 Lecture Topics These are the headings of the paragraphs into which ASTR 1023 lectures are divided. Use them to check your notes for completeness, and to see how the course is organized. It is also a good idea to cross-check these topics with your reading assignments, because some topics ar ...
... ASTR 1023 Lecture Topics These are the headings of the paragraphs into which ASTR 1023 lectures are divided. Use them to check your notes for completeness, and to see how the course is organized. It is also a good idea to cross-check these topics with your reading assignments, because some topics ar ...
Astronomy 112: The Physics of Stars Class 12 Notes: Convection in
... occurs because a large opacity means that the temperature gradient must become steep to carry the same heat flow. The star responds by developing a steeper temperature gradient until it becomes so steep that it exceeds the adiabatic gradient, at which point convection starts. Since κ generally incre ...
... occurs because a large opacity means that the temperature gradient must become steep to carry the same heat flow. The star responds by developing a steeper temperature gradient until it becomes so steep that it exceeds the adiabatic gradient, at which point convection starts. Since κ generally incre ...
1 Origin of the Elements. Isotopes and Atomic Weights
... mass 10 Mþ , and only 8 ð 104 y for a star of 50 Mþ ; i.e. the more massive the star, the more rapidly it consumes its nuclear fuel. Further catastrophic changes may then occur which result in much of the stellar material being ejected into space, where it becomes incorporated together with further ...
... mass 10 Mþ , and only 8 ð 104 y for a star of 50 Mþ ; i.e. the more massive the star, the more rapidly it consumes its nuclear fuel. Further catastrophic changes may then occur which result in much of the stellar material being ejected into space, where it becomes incorporated together with further ...
The Little Star That Could - Challenger Learning Center
... solar system Star – a: a natural luminous body visible in the sky especially at night b: a self-luminous gaseous spheroidal celestial body of great mass which produces energy by means of nuclear fusion reactions Sun – the luminous celestial body around which the earth and other planets revolve, from ...
... solar system Star – a: a natural luminous body visible in the sky especially at night b: a self-luminous gaseous spheroidal celestial body of great mass which produces energy by means of nuclear fusion reactions Sun – the luminous celestial body around which the earth and other planets revolve, from ...
... brighter than mv (C), and out to a distance d. In other words, we compute the number of field stars inside a cone with vertex at the observer and base at the trapezium, centered on component A and with a height equal to the distance to the trapezium. Note that by taking the height of the cone equal ...
How do stars orbit in our galaxy?
... and expel them into space via supernovae and stellar winds. The supernovae and winds create hot bubbles in the interstellar medium, but the gas within these bubbles gradually slows and cools as they expand. Eventually, this gas cools enough to collect into clouds of atomic hydrogen. Further cooling ...
... and expel them into space via supernovae and stellar winds. The supernovae and winds create hot bubbles in the interstellar medium, but the gas within these bubbles gradually slows and cools as they expand. Eventually, this gas cools enough to collect into clouds of atomic hydrogen. Further cooling ...
Kick velocity
... van den Heuvel 2004, 2007) that among Be/X-ray binaries there is a group of systems with small eccentricities. But they suffered one SN explosion and there was no Roche-lobe overflow. This means that kicks in these systems were low. The same is true for some of NS+NS binaries. The proposed mechanism ...
... van den Heuvel 2004, 2007) that among Be/X-ray binaries there is a group of systems with small eccentricities. But they suffered one SN explosion and there was no Roche-lobe overflow. This means that kicks in these systems were low. The same is true for some of NS+NS binaries. The proposed mechanism ...
CONTINUING GALACTIC FORMATION
... -There are tremendous quantities of radio signals emitted by the Milky Way's nucleus. -The immediate environment surrounding many hot blue stars. -Novae and Supernovae art frequent. -Observation of supergiant stars of short life times indicates that stars are being formed in the galactic center. -Th ...
... -There are tremendous quantities of radio signals emitted by the Milky Way's nucleus. -The immediate environment surrounding many hot blue stars. -Novae and Supernovae art frequent. -Observation of supergiant stars of short life times indicates that stars are being formed in the galactic center. -Th ...
IK Pegasi
IK Pegasi (or HR 8210) is a binary star system in the constellation Pegasus. It is just luminous enough to be seen with the unaided eye, at a distance of about 150 light years from the Solar System.The primary (IK Pegasi A) is an A-type main-sequence star that displays minor pulsations in luminosity. It is categorized as a Delta Scuti variable star and it has a periodic cycle of luminosity variation that repeats itself about 22.9 times per day. Its companion (IK Pegasi B) is a massive white dwarf—a star that has evolved past the main sequence and is no longer generating energy through nuclear fusion. They orbit each other every 21.7 days with an average separation of about 31 million kilometres, or 19 million miles, or 0.21 astronomical units (AU). This is smaller than the orbit of Mercury around the Sun.IK Pegasi B is the nearest known supernova progenitor candidate. When the primary begins to evolve into a red giant, it is expected to grow to a radius where the white dwarf can accrete matter from the expanded gaseous envelope. When the white dwarf approaches the Chandrasekhar limit of 1.44 solar masses (M☉), it may explode as a Type Ia supernova.