Galaxies, stars and planets
... Much of astronomy concerns quantities such as distances, masses, temperatures, etc. In all of these cases, units of measurement are important. Physical quantities are generally the result of multiplying together a number and a unit of measurement. Thus a distance such as 5.2 metres is really the res ...
... Much of astronomy concerns quantities such as distances, masses, temperatures, etc. In all of these cases, units of measurement are important. Physical quantities are generally the result of multiplying together a number and a unit of measurement. Thus a distance such as 5.2 metres is really the res ...
The cosmic distance scale
... distances much further away than the Virgo cluster (and we do!). We would need a type of object that is much brighter than a Cepheid that also has a known absolute magnitude so that we know how much light is emitted. Type Ia supernovae1 are very bright, in fact about 14 magnitudes brighter than Ceph ...
... distances much further away than the Virgo cluster (and we do!). We would need a type of object that is much brighter than a Cepheid that also has a known absolute magnitude so that we know how much light is emitted. Type Ia supernovae1 are very bright, in fact about 14 magnitudes brighter than Ceph ...
March 2016 BRAS Addendum Newsletter
... times? Testimony of Aratus, Cicero, Horace, Seneca, and Ptolemy – all of these ancient writers described Sirius with terms that can only be described as “ruddy”, “reddish”, “blazing as fire”, etc. Al Sufi, in the tenth century does not mention Sirius among stars which he classified as red. There are ...
... times? Testimony of Aratus, Cicero, Horace, Seneca, and Ptolemy – all of these ancient writers described Sirius with terms that can only be described as “ruddy”, “reddish”, “blazing as fire”, etc. Al Sufi, in the tenth century does not mention Sirius among stars which he classified as red. There are ...
Galaxies at High Redshift Encyclopedia of Astronomy & Astrophysics eaa.iop.org Mauro Giavalisco
... the light departed them, carrying information on their properties at that time. Observations of objects with very high redshifts play a central role in cosmology because they provide insight into the epochs and the mechanisms of GALAXY FORMATION, if one can reach redshifts that are high enough to co ...
... the light departed them, carrying information on their properties at that time. Observations of objects with very high redshifts play a central role in cosmology because they provide insight into the epochs and the mechanisms of GALAXY FORMATION, if one can reach redshifts that are high enough to co ...
Future of asteroseismology
... • Multi-object spectrographs (but hard to ensure radial-velocity precision) • Intensity observations of multiple stars from space (HK lecture) ...
... • Multi-object spectrographs (but hard to ensure radial-velocity precision) • Intensity observations of multiple stars from space (HK lecture) ...
T
... The long-term precision of the instrument cannot be checked easily because it requires a long time base on one hand, and the knowledge of stable stellar sources on the other hand. Especially the latter point represents a new challenge since the intrinsic stability of the stars has never been studied ...
... The long-term precision of the instrument cannot be checked easily because it requires a long time base on one hand, and the knowledge of stable stellar sources on the other hand. Especially the latter point represents a new challenge since the intrinsic stability of the stars has never been studied ...
Slides
... “An active galactic nucleus (AGN) is a compact region at the center of a galaxy which has a much higher than normal luminosity over some or all of the electromagnetic spectrum. The radiation from AGN is believed to be a result of accretion on to a super-massive black hole at the centre of the host g ...
... “An active galactic nucleus (AGN) is a compact region at the center of a galaxy which has a much higher than normal luminosity over some or all of the electromagnetic spectrum. The radiation from AGN is believed to be a result of accretion on to a super-massive black hole at the centre of the host g ...
1: Properties of Pulsars
... electrons and protons form neutrons. The core is hence made of an ensemble of neutrons acting like a fluid with the unusual properties of being super-fluid and super-conducting (no frictional or electrical resistance). The pressure in the core is as high as 1014 grams per cubic centimetre. Depending ...
... electrons and protons form neutrons. The core is hence made of an ensemble of neutrons acting like a fluid with the unusual properties of being super-fluid and super-conducting (no frictional or electrical resistance). The pressure in the core is as high as 1014 grams per cubic centimetre. Depending ...
The Formation and Survival of Discs in a Lambda
... Major mergers and instabilities, which arise when accreting cold gas is misaligned with the stellar disc, trigger a transfer of mass from the discs to the spheroids. In some cases, discs are destroyed, while in others, they survive or reform. This suggests that the survival probability of discs depe ...
... Major mergers and instabilities, which arise when accreting cold gas is misaligned with the stellar disc, trigger a transfer of mass from the discs to the spheroids. In some cases, discs are destroyed, while in others, they survive or reform. This suggests that the survival probability of discs depe ...
Potential for Life on the Terrestrial Planets
... decades to discuss the future of the fast-expanding field of exoplanet research. Now more than 860 exoplanets are known and during the near future observing facilities will become extremely powerful. After the pioneering discovery of the first transiting superEarth CoRoT-7b by the CoRoT space observ ...
... decades to discuss the future of the fast-expanding field of exoplanet research. Now more than 860 exoplanets are known and during the near future observing facilities will become extremely powerful. After the pioneering discovery of the first transiting superEarth CoRoT-7b by the CoRoT space observ ...
Star Map - Science Centre
... front of Saturn, resulting in an alignment of Earth and Saturn with the Sun. This known as an opposition as Saturn and the Sun become directly opposite each other, as seen from Earth. ...
... front of Saturn, resulting in an alignment of Earth and Saturn with the Sun. This known as an opposition as Saturn and the Sun become directly opposite each other, as seen from Earth. ...
Investigating the Low-Mass Stellar Initial Mass Function in
... Surveys (ACS) and Wide Field Camera 3 (WFC3) for 3 different fields in Draco ...
... Surveys (ACS) and Wide Field Camera 3 (WFC3) for 3 different fields in Draco ...
The diameter of the CoRoT target HD 49933
... Context. The interpretation of stellar pulsations in terms of internal structure depends on the knowledge of the fundamental stellar parameters. Long-base interferometers permit us to determine very accurate stellar radii, which are independent constraints for stellar models that help us to locate t ...
... Context. The interpretation of stellar pulsations in terms of internal structure depends on the knowledge of the fundamental stellar parameters. Long-base interferometers permit us to determine very accurate stellar radii, which are independent constraints for stellar models that help us to locate t ...
A Global Citizen of the Skies
... Figure 1 and 2 show two examples of stellar constellations created during the activity a member of the ‘Natives’ and ‘Explorers’ group, respectively. Already a clear impact of the cultural background of each group can be detected. The ‘Natives’ constellation targets an animal rather than an artifici ...
... Figure 1 and 2 show two examples of stellar constellations created during the activity a member of the ‘Natives’ and ‘Explorers’ group, respectively. Already a clear impact of the cultural background of each group can be detected. The ‘Natives’ constellation targets an animal rather than an artifici ...
Asymmetric Star Formation Efficiency Due to Ram Pressure Stripping
... It uses up to seven billion particles per individual simulation to follow the physics of the galaxy processes, considering dark matter and gas particles. The gas particles fall into the centres of dark matter haloes, depending on how they have cooled and whether they reach a density greater than a c ...
... It uses up to seven billion particles per individual simulation to follow the physics of the galaxy processes, considering dark matter and gas particles. The gas particles fall into the centres of dark matter haloes, depending on how they have cooled and whether they reach a density greater than a c ...
“End-of-the-Line” W UMa Eclipsing Binary V523
... they manage to coexist with remarkable stability. Overcontact binaries are found across almost the entire range of stellar spectral types, from the hot ...
... they manage to coexist with remarkable stability. Overcontact binaries are found across almost the entire range of stellar spectral types, from the hot ...
Chemical Composition and Evolutionary Status of the Ap Star HD
... a strong dependence is seen. If this dependence was due to an improper choice of the temperature, then the model with Teff ≈ 9500 K should be applied in the calculations to eliminate it, which is inconsistent with the observations. For our stratification analysis, we chose 32 iron lines, 16 calcium li ...
... a strong dependence is seen. If this dependence was due to an improper choice of the temperature, then the model with Teff ≈ 9500 K should be applied in the calculations to eliminate it, which is inconsistent with the observations. For our stratification analysis, we chose 32 iron lines, 16 calcium li ...
Document
... • Magnetic field of sun interacts with proto-planetary disk • Slows down the sun’s rotation ...
... • Magnetic field of sun interacts with proto-planetary disk • Slows down the sun’s rotation ...
ppt
... The parametric methods work only when there are two proper-motion groups (cluster and field stars) distributed according to normal bivariate function. The most common departure from these assumptions is the non-Gaussian shape of the field proper-motion distribution (Sun’s peculiar motion + Galactic ...
... The parametric methods work only when there are two proper-motion groups (cluster and field stars) distributed according to normal bivariate function. The most common departure from these assumptions is the non-Gaussian shape of the field proper-motion distribution (Sun’s peculiar motion + Galactic ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.