Betelgeuse - TeacherWeb
... • In 1995 the Hubble’s telescope discovered Betelgeuse. It has been noticed before but never named. In 1836 Sir John Frederick William Hersche noticed that Betelgeuse had changed in brightness. ...
... • In 1995 the Hubble’s telescope discovered Betelgeuse. It has been noticed before but never named. In 1836 Sir John Frederick William Hersche noticed that Betelgeuse had changed in brightness. ...
Stages of star formation (the classical view)
... The protostar becomes a pre-main sequence star (T Tauri star). However, for a high-mass star tKH<< tff (for a 50 Msol star, tKH= 3x104 yr) The star has not enough time to accrete more than ~10 Msol before starting to burn hydrogen, ionizing the material around the star, and disrupting the dense core ...
... The protostar becomes a pre-main sequence star (T Tauri star). However, for a high-mass star tKH<< tff (for a 50 Msol star, tKH= 3x104 yr) The star has not enough time to accrete more than ~10 Msol before starting to burn hydrogen, ionizing the material around the star, and disrupting the dense core ...
Sample pages 1 PDF
... Do you remember the first night that you stood for the very first time under a clear night sky and gazed with bewilderment at its beauty? And did you think something like this as you watched: ‘‘How many stars there are! How can anyone make any sense of this mass of stars?’’ An attentive observer wil ...
... Do you remember the first night that you stood for the very first time under a clear night sky and gazed with bewilderment at its beauty? And did you think something like this as you watched: ‘‘How many stars there are! How can anyone make any sense of this mass of stars?’’ An attentive observer wil ...
Extrasolar Cosmochemistry
... formation in protoplanetary disks. Then, in Section 6, we describe results that pertain to the evolution of planetesimals beyond their phase of nebular formation. Finally, in Section 7, we present our conclusions and suggest directions of future research. ...
... formation in protoplanetary disks. Then, in Section 6, we describe results that pertain to the evolution of planetesimals beyond their phase of nebular formation. Finally, in Section 7, we present our conclusions and suggest directions of future research. ...
WORD - Astrophysics
... overcome crowding, and a 100m class telescope is required to study the brighter galaxies at their half-light radius - without it work is limited to the less representative outer regions where crowding is less of an issue. The more luminous elliptical ...
... overcome crowding, and a 100m class telescope is required to study the brighter galaxies at their half-light radius - without it work is limited to the less representative outer regions where crowding is less of an issue. The more luminous elliptical ...
Cygnus X-2, super-Eddington mass transfer, and pulsar binaries
... small inclinations would imply M 1 . 100 M(, again clearly incompatible with the very strong observational evidence for a neutron-star primary. A still stronger argument can be constructed on the basis that the spectral type of the secondary is not observed to vary during the orbital cycle. 2.3 A he ...
... small inclinations would imply M 1 . 100 M(, again clearly incompatible with the very strong observational evidence for a neutron-star primary. A still stronger argument can be constructed on the basis that the spectral type of the secondary is not observed to vary during the orbital cycle. 2.3 A he ...
The High Resolution Camera CXC Newsletter
... for all of them. We classified sources as highly variable or outbursting (with subclasses short vs. long outbursts and activity periods). 129 sources could be classified as X-ray binaries due to their position in globular clusters or their strong time variability (see Fig. 2). We detected seven supe ...
... for all of them. We classified sources as highly variable or outbursting (with subclasses short vs. long outbursts and activity periods). 129 sources could be classified as X-ray binaries due to their position in globular clusters or their strong time variability (see Fig. 2). We detected seven supe ...
Science drivers for GLAO at LBT
... Oph 11 is the most extreme low-mass, wide (>243 AU) binary known. Oph 16 is the 4th least bound system while Oph 11 is the least bound with Vesc<0.5 km/s. Such systems cannot be formed by “ejection” mechanisms. ...
... Oph 11 is the most extreme low-mass, wide (>243 AU) binary known. Oph 16 is the 4th least bound system while Oph 11 is the least bound with Vesc<0.5 km/s. Such systems cannot be formed by “ejection” mechanisms. ...
- Cosmotography
... mag), although a Z = 0.001, 10 Gyr model is consistent with the blue edge of the observed RGB. Presumably a 10 Gyr model with Z ∼ 0.002 would also be consistent with the data, while perhaps providing a better match to the observed CMD slope. We conclude that, if the bulk of the RGB stars are old (> ...
... mag), although a Z = 0.001, 10 Gyr model is consistent with the blue edge of the observed RGB. Presumably a 10 Gyr model with Z ∼ 0.002 would also be consistent with the data, while perhaps providing a better match to the observed CMD slope. We conclude that, if the bulk of the RGB stars are old (> ...
Elliptical galaxies
... •Due to seeing, stars have finite extent (not observed as point sources). •The light profile of stars is known as the PSF: Point Spread Function. •The effect of the seeing is to blur an otherwise sharp image. If in absence of seeing the surface brightness of an object at a position R’ is It(R’), the ...
... •Due to seeing, stars have finite extent (not observed as point sources). •The light profile of stars is known as the PSF: Point Spread Function. •The effect of the seeing is to blur an otherwise sharp image. If in absence of seeing the surface brightness of an object at a position R’ is It(R’), the ...
- ANU Repository
... that can be compared with those around solar-type stars to test models of planet formation (e.g. Gaidos & Mann 2014). There have been several recent works estimating the occurrence of planets around M dwarfs, the distribution with radii, and the number of planets within a ‘habitable zone’ (HZ) bound ...
... that can be compared with those around solar-type stars to test models of planet formation (e.g. Gaidos & Mann 2014). There have been several recent works estimating the occurrence of planets around M dwarfs, the distribution with radii, and the number of planets within a ‘habitable zone’ (HZ) bound ...
Wolf-Rayet Stars
... stars first identified in 1867 by C. J. E. Wolf and G. Rayet. Unlike the spectra of most stars, which are dominated by narrow absorption lines, the spectra of W-R stars show broad emission lines. The rich emission line spectrum makes them easy to identify, by spectroscopic observations, even at large ...
... stars first identified in 1867 by C. J. E. Wolf and G. Rayet. Unlike the spectra of most stars, which are dominated by narrow absorption lines, the spectra of W-R stars show broad emission lines. The rich emission line spectrum makes them easy to identify, by spectroscopic observations, even at large ...
Astronomy Astrophysics NGC 7419 as a template for red supergiant clusters &
... We obtained Strömgren photometry of the open cluster NGC 7419 using ALFOSC on the Nordic Optical Telescope at the Roque de los Muchachos Observatory (La Palma, Spain) on the night of October 3, 2005. ALFOSC allows observations in different modes. In imaging mode the camera covers a field of 6. 5 × 6 ...
... We obtained Strömgren photometry of the open cluster NGC 7419 using ALFOSC on the Nordic Optical Telescope at the Roque de los Muchachos Observatory (La Palma, Spain) on the night of October 3, 2005. ALFOSC allows observations in different modes. In imaging mode the camera covers a field of 6. 5 × 6 ...
Three newly discovered sub-Jupiter-mass planets: WASP
... We report the discovery of the transiting exoplanets WASP-69b, WASP-70Ab and WASP84b, each of which orbits a bright star (V ∼ 10). WASP-69b is a bloated Saturn-mass planet (0.26 MJup , 1.06 RJup ) in a 3.868-d period around an active, ∼1-Gyr, mid-K dwarf. ROSAT detected X-rays 60±27 arcsec from WASP ...
... We report the discovery of the transiting exoplanets WASP-69b, WASP-70Ab and WASP84b, each of which orbits a bright star (V ∼ 10). WASP-69b is a bloated Saturn-mass planet (0.26 MJup , 1.06 RJup ) in a 3.868-d period around an active, ∼1-Gyr, mid-K dwarf. ROSAT detected X-rays 60±27 arcsec from WASP ...
hwd_ewd_v3 - X-ray and Observational Astronomy Group
... the surface) causes rapid downward diffusion of elements heavier than the principal H or He component. Hence, Schatzman predicted that white dwarf atmospheres should be extremely pure. Consequently, the spectra should be devoid of most elements, showing signatures of only hydrogen and, possibly, hel ...
... the surface) causes rapid downward diffusion of elements heavier than the principal H or He component. Hence, Schatzman predicted that white dwarf atmospheres should be extremely pure. Consequently, the spectra should be devoid of most elements, showing signatures of only hydrogen and, possibly, hel ...
PPT Only - Harvard-Smithsonian Center for Astrophysics
... (All the) Maps of “Giant” Outflows, c. 2002 ...
... (All the) Maps of “Giant” Outflows, c. 2002 ...
Lyra
Lyra (/ˈlaɪərə/; Latin for lyre, from Greek λύρα) is a small constellation. It is one of 48 listed by the 2nd century astronomer Ptolemy, and is one of the 88 constellations recognized by the International Astronomical Union. Lyra was often represented on star maps as a vulture or an eagle carrying a lyre, and hence sometimes referred to as Aquila Cadens or Vultur Cadens. Beginning at the north, Lyra is bordered by Draco, Hercules, Vulpecula, and Cygnus. Lyra is visible from the northern hemisphere from spring through autumn, and nearly overhead, in temperate latitudes, during the summer months. From the southern hemisphere, it is visible low in the northern sky during the winter months.The lucida or brightest star—and one of the brightest stars in the sky—is the white main sequence star Vega, a corner of the Summer Triangle. Beta Lyrae is the prototype of a class of stars known as Beta Lyrae variables, binary stars so close to each other that they become egg-shaped and material flows from one to the other. Epsilon Lyrae, known informally as the Double Double, is a complex multiple star system. Lyra also hosts the Ring Nebula, the second-discovered and best-known planetary nebula.