New Worlds, New Horizons in Astronomy and
... scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal governme ...
... scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal governme ...
A Star - Cloudy Nights
... All the stars you can see without a telescope, including our Sun, are located in the same spiral arm of the Milky Way galaxy. Even though these stars are our neighbors, we can't visit them. They are too far away. Using current technology, it would take thousands of years to travel to our closest ste ...
... All the stars you can see without a telescope, including our Sun, are located in the same spiral arm of the Milky Way galaxy. Even though these stars are our neighbors, we can't visit them. They are too far away. Using current technology, it would take thousands of years to travel to our closest ste ...
Hint of a transiting extended atmosphere on 55 Cancri b⋆
... Chandra ACIS-S coverage (Weisskopf et al. 2002; Garmire et al. 2003) of each HST visit (Chandra ObsIDs 14401 & 14402). The observations were scheduled to begin 4 h before mid-transit of 55 Cnc e, with precise start times of 2012-03-07 UT 02:13 and 2012-04-05 UT 12:50. The scheduled exposure times we ...
... Chandra ACIS-S coverage (Weisskopf et al. 2002; Garmire et al. 2003) of each HST visit (Chandra ObsIDs 14401 & 14402). The observations were scheduled to begin 4 h before mid-transit of 55 Cnc e, with precise start times of 2012-03-07 UT 02:13 and 2012-04-05 UT 12:50. The scheduled exposure times we ...
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. ...
Untitled - NMSU Astronomy
... with numbers like ten, one hundred, three thousand, ten million, a billion, or even a trillion. But what about a number like one million trillion? Or, four thousand one hundred and fifty six million billion? Such numbers are too cumbersome to handle with words. Scientists use something called “Scien ...
... with numbers like ten, one hundred, three thousand, ten million, a billion, or even a trillion. But what about a number like one million trillion? Or, four thousand one hundred and fifty six million billion? Such numbers are too cumbersome to handle with words. Scientists use something called “Scien ...
Star Formation in the Rosette Complex
... ship for a total of 30 cluster sources and to extend the list of known PMS candidates to 21. They subsequently identified members coincident with ROSAT point source catalogs and compared their properties to the rest of the sample. Six of the PMS candidates were confirmed as X-ray sources. In Figure ...
... ship for a total of 30 cluster sources and to extend the list of known PMS candidates to 21. They subsequently identified members coincident with ROSAT point source catalogs and compared their properties to the rest of the sample. Six of the PMS candidates were confirmed as X-ray sources. In Figure ...
A search for a new class of pulsating DA white dwarf stars in the DB
... The process of atomic diffusion is important in many stellar astrophysical situations. It is a competition between gravitational settling and radiative levitation with any kind of turbulent mixing – particularly convection – potentially (usually) quenching the processes. Most importantly in the cont ...
... The process of atomic diffusion is important in many stellar astrophysical situations. It is a competition between gravitational settling and radiative levitation with any kind of turbulent mixing – particularly convection – potentially (usually) quenching the processes. Most importantly in the cont ...
The Multitude of Molecular Hydrogen Knots in the Helix Nebula 1
... picture of the cometary knots reveals that they are neutral gas condensations that appear as comet like structures with rims bright in Hα and tails that appear as shadows in [OIII] and that point away from the central star. The rim of low-excitation ionize gas has a steep temperature gradient indica ...
... picture of the cometary knots reveals that they are neutral gas condensations that appear as comet like structures with rims bright in Hα and tails that appear as shadows in [OIII] and that point away from the central star. The rim of low-excitation ionize gas has a steep temperature gradient indica ...
disappearance of comet c/2010 x1 (elenin): gone with a whimper
... inbound at 4.2 AU, this long-period comet was predicted to become very bright when near perihelion, at 0.48 AU on 2011 September 10. Observations starting 2011 February (heliocentric distance ∼3.5 AU) indeed show the comet to brighten by about 11 mag, with most of the increase occurring inside 1 AU ...
... inbound at 4.2 AU, this long-period comet was predicted to become very bright when near perihelion, at 0.48 AU on 2011 September 10. Observations starting 2011 February (heliocentric distance ∼3.5 AU) indeed show the comet to brighten by about 11 mag, with most of the increase occurring inside 1 AU ...
structure and evolution of white dwarfs and their
... Dreizler & Werner 1996) implies that He-rich white dwarfs must temporarily be seen as DA stars due to some physical process. ...
... Dreizler & Werner 1996) implies that He-rich white dwarfs must temporarily be seen as DA stars due to some physical process. ...
The Secular and Rotational Brightness Variations of Neptune
... transformations but all the data analyzed here have been transformed. Formal errors are not available for these observations though they are estimated to be a few hundredths of a magnitude or less based on scatter in the data obtained over short periods of time as well as the likely uncertainties in ...
... transformations but all the data analyzed here have been transformed. Formal errors are not available for these observations though they are estimated to be a few hundredths of a magnitude or less based on scatter in the data obtained over short periods of time as well as the likely uncertainties in ...
Chapter 15 Stars, Galaxies and Universe
... • Careful measurements have shown that most galaxies are moving away from each other and that the universe is expanding. With these findings, scientists have worked backward in time to figure out how the universe formed. ...
... • Careful measurements have shown that most galaxies are moving away from each other and that the universe is expanding. With these findings, scientists have worked backward in time to figure out how the universe formed. ...
December 2011
... moving through space) are probably made of rock or metal so they often survive quite a long time when they enter Earth’s atmosphere. The Geminid meteors also enter the atmosphere comparatively slowly at about 35 km/second compared with other showers that enter at over 75 km/second. As a result of th ...
... moving through space) are probably made of rock or metal so they often survive quite a long time when they enter Earth’s atmosphere. The Geminid meteors also enter the atmosphere comparatively slowly at about 35 km/second compared with other showers that enter at over 75 km/second. As a result of th ...
here - Ira-Inaf
... sources in the galactic plane. This latter survey differs from the Wouterloot and Brand (1989) survey in that the CS(2-1) line traces denser molecular gas than the CO(1–0) line, and the Bronfman et al. catalogue includes full coverage of the first galactic quadrant. From these 3 sources, we selected ...
... sources in the galactic plane. This latter survey differs from the Wouterloot and Brand (1989) survey in that the CS(2-1) line traces denser molecular gas than the CO(1–0) line, and the Bronfman et al. catalogue includes full coverage of the first galactic quadrant. From these 3 sources, we selected ...
Conference Abstract Booklet here.
... We analyse the multiwavelength theoretical (UBVRIJKL) and observed (VIJHK3.6/4.5) light curves of Cepheid variables using the Fourier decomposition and principal component analysis methods. The theoretical Cepheid light curves are obtained using the full amplitude, nonlinear, convective hydrodynamic ...
... We analyse the multiwavelength theoretical (UBVRIJKL) and observed (VIJHK3.6/4.5) light curves of Cepheid variables using the Fourier decomposition and principal component analysis methods. The theoretical Cepheid light curves are obtained using the full amplitude, nonlinear, convective hydrodynamic ...
Abstracts - Physics of Evolved Stars 2015
... before entering the high mass-loss phase. To evolve into a post-AGB star, with a white dwarf cooling at the center, OH/IR stars must lose more than ~3 solar masses during the superwind. At a rate on the order of 10^-4 solar masses per year, this phase must last at least 10^4 years. This contrasts he ...
... before entering the high mass-loss phase. To evolve into a post-AGB star, with a white dwarf cooling at the center, OH/IR stars must lose more than ~3 solar masses during the superwind. At a rate on the order of 10^-4 solar masses per year, this phase must last at least 10^4 years. This contrasts he ...
SPATIAL STUDY WITH THE VERY LARGE TELESCOPE OF A NEW
... data to produce the resulting color composite image presented in Figure 2b (see also the ESO press release, photo 12b/02,9 which presents a larger color composite image corresponding to the field of view shown in Fig. 5). Thanks to very good seeing conditions and smaller detector pixel size, the two ...
... data to produce the resulting color composite image presented in Figure 2b (see also the ESO press release, photo 12b/02,9 which presents a larger color composite image corresponding to the field of view shown in Fig. 5). Thanks to very good seeing conditions and smaller detector pixel size, the two ...
Chemical abundances and winds of massive stars in M31: a B
... a combination of observations of H ii regions and supernova remnants, deriving −0.03 ± 0.01 dex kpc−1 . Hence, OB 10 is expected to have a metallicity of ∼9.1 dex, a factor of two greater than the Galactic solar neighbourhood value. In this paper, William Hershel Telescope (WHT) spectroscopy of OB 1 ...
... a combination of observations of H ii regions and supernova remnants, deriving −0.03 ± 0.01 dex kpc−1 . Hence, OB 10 is expected to have a metallicity of ∼9.1 dex, a factor of two greater than the Galactic solar neighbourhood value. In this paper, William Hershel Telescope (WHT) spectroscopy of OB 1 ...
Globular Clusters
... a much wider population, partially disrupted and spread out throughout the Galactic halo and far beyond. In this respect, it has been estimated that, within the next ten billion years or so, most of the present Galactic GCs could disappear. On the other hand, we know today that four clusters in Sagi ...
... a much wider population, partially disrupted and spread out throughout the Galactic halo and far beyond. In this respect, it has been estimated that, within the next ten billion years or so, most of the present Galactic GCs could disappear. On the other hand, we know today that four clusters in Sagi ...
Hubble Deep Field
The Hubble Deep Field (HDF) is an image of a small region in the constellation Ursa Major, constructed from a series of observations by the Hubble Space Telescope. It covers an area 2.5 arcminutes across, about one 24-millionth of the whole sky, which is equivalent in angular size to a 65 mm tennis ball at a distance of 100 metres. The image was assembled from 342 separate exposures taken with the Space Telescope's Wide Field and Planetary Camera 2 over ten consecutive days between December 18 and December 28, 1995.The field is so small that only a few foreground stars in the Milky Way lie within it; thus, almost all of the 3,000 objects in the image are galaxies, some of which are among the youngest and most distant known. By revealing such large numbers of very young galaxies, the HDF has become a landmark image in the study of the early universe, with the associated scientific paper having received over 900 citations by the end of 2014.Three years after the HDF observations were taken, a region in the south celestial hemisphere was imaged in a similar way and named the Hubble Deep Field South. The similarities between the two regions strengthened the belief that the universe is uniform over large scales and that the Earth occupies a typical region in the Universe (the cosmological principle). A wider but shallower survey was also made as part of the Great Observatories Origins Deep Survey. In 2004 a deeper image, known as the Hubble Ultra-Deep Field (HUDF), was constructed from a few months of light exposure. The HUDF image was at the time the most sensitive astronomical image ever made at visible wavelengths, and it remained so until the Hubble Extreme Deep Field (XDF) was released in 2012.