Debris discs around M stars: non-existence versus non
... Motivated by the reported dearth of debris discs around M stars, we use survival models to study the occurrence of planetesimal discs around them. These survival models describe a planetesimal disc with a small number of parameters, determine if it may survive a series of dynamical processes and com ...
... Motivated by the reported dearth of debris discs around M stars, we use survival models to study the occurrence of planetesimal discs around them. These survival models describe a planetesimal disc with a small number of parameters, determine if it may survive a series of dynamical processes and com ...
Lecture Notes
... considering the whole electromagnetic spectrum including cosmic rays-X-rays at the short 's region to radio waves and microwave radiation at long 's region; visible light is only a small part of this spectrum (FIG. 5.3). The range of visible light is from approximately 390-710 nm (nanometer=10-9 ...
... considering the whole electromagnetic spectrum including cosmic rays-X-rays at the short 's region to radio waves and microwave radiation at long 's region; visible light is only a small part of this spectrum (FIG. 5.3). The range of visible light is from approximately 390-710 nm (nanometer=10-9 ...
Some notes on the Inka constellations
... its location the names and significance of celestial objects. It is important to emphasize that within the astronomy of the Inkas there are two types of constellations: (a) Stellar constellations or bright stars, made up of individual bright stars which constitute a ‘constellation’ and grouped togeth ...
... its location the names and significance of celestial objects. It is important to emphasize that within the astronomy of the Inkas there are two types of constellations: (a) Stellar constellations or bright stars, made up of individual bright stars which constitute a ‘constellation’ and grouped togeth ...
A nanometer notch filter with high rejection and throughput
... wavelength, (AL = 694.3 nm), and > 50% transmission within -0.5 nm of /zL and a throughput beam product of f/50X 1 cm. Dielectric filters are available with - lo6 attenuation but with bandwidths of 2 10 nm, too broad in the context of forward scattering. Absorption filters of the same material as th ...
... wavelength, (AL = 694.3 nm), and > 50% transmission within -0.5 nm of /zL and a throughput beam product of f/50X 1 cm. Dielectric filters are available with - lo6 attenuation but with bandwidths of 2 10 nm, too broad in the context of forward scattering. Absorption filters of the same material as th ...
Chapter 5. IR Spectroscopy and Raman Scattering
... The possible vibrations of a molecule are sensitive to IR absorption if the vibration results in a change in the dipole moment, u, of the molecule. The dipole moment is the product of the charge times distance and is similar to the moment of inertia in mechanics except that charge is the weighting f ...
... The possible vibrations of a molecule are sensitive to IR absorption if the vibration results in a change in the dipole moment, u, of the molecule. The dipole moment is the product of the charge times distance and is similar to the moment of inertia in mechanics except that charge is the weighting f ...
Supernova! Toledo Astronomical Association, February 2009
... In just a few weeks, a supernova can give off as much energy as the sun in it’s entire lifetime RARE On average, only one every 50 years in the entire Milky Way FAST Up to 3% of the speed of light ...
... In just a few weeks, a supernova can give off as much energy as the sun in it’s entire lifetime RARE On average, only one every 50 years in the entire Milky Way FAST Up to 3% of the speed of light ...
Article PDF - IOPscience
... most limiting factor. Of studies that speciÐcally measure surface brightness in the appropriate fashion, H I measurements are not always available, further limiting the available data. It would be desirable to also have CO measurements as a tracer of the molecular gas, but there are essentially no p ...
... most limiting factor. Of studies that speciÐcally measure surface brightness in the appropriate fashion, H I measurements are not always available, further limiting the available data. It would be desirable to also have CO measurements as a tracer of the molecular gas, but there are essentially no p ...
Homework Set #6 Due: 3-28-14
... on the polarization direction. For a given crystal and direction of the light, two polarization modes exist for which there is a definite index of refraction. These are referred to as the extraordinary and ordinary modes. When light is incident on an anisotropic medium at non-normal incidence it wil ...
... on the polarization direction. For a given crystal and direction of the light, two polarization modes exist for which there is a definite index of refraction. These are referred to as the extraordinary and ordinary modes. When light is incident on an anisotropic medium at non-normal incidence it wil ...
THE CHEMICAL COMPOSITION AND AGE OF THE METAL
... We have combined new high-resolution spectra obtained with the Hubble Space Telescope (HST) and ground-based facilities to make a comprehensive new abundance analysis of the metal-poor, halo star BD +17 3248. We have detected the third r-process peak elements osmium, platinum, and (for the first tim ...
... We have combined new high-resolution spectra obtained with the Hubble Space Telescope (HST) and ground-based facilities to make a comprehensive new abundance analysis of the metal-poor, halo star BD +17 3248. We have detected the third r-process peak elements osmium, platinum, and (for the first tim ...
GEOCENTRISM UNIVERSE – THE EARTH IS FIXED - luke-jr
... aether, however, will allow it to transcribe a path through the zodiac each year. Hence, as the aether rotates once per day around the earth, the sun rotates with it, and the sun will come back to almost the same position each day, except that it will be 1/365th ahead of where it was the day before. ...
... aether, however, will allow it to transcribe a path through the zodiac each year. Hence, as the aether rotates once per day around the earth, the sun rotates with it, and the sun will come back to almost the same position each day, except that it will be 1/365th ahead of where it was the day before. ...
Core-Halo Age Gradients and Star Formation in the Orion Nebula
... slow mode in the star formation process of massive stars, such as competitive accretion of core gas or stellar mergers (Zinnecker & Yorke 2007). In this context, we present a new empirical finding: that PMS stars are younger in the core region than in the outer regions of two nearby rich clusters, t ...
... slow mode in the star formation process of massive stars, such as competitive accretion of core gas or stellar mergers (Zinnecker & Yorke 2007). In this context, we present a new empirical finding: that PMS stars are younger in the core region than in the outer regions of two nearby rich clusters, t ...
to view our telescope buyers guide-(120K PDF).
... 7. Keep in mind the size of the telescope. Some larger scopes can be over 100 pounds. Often a smaller scope will get used more often because it is easier to move and set up. 8. Newer small computerized “GOTO” style telescopes will automatically position the telescope to an object you select in its i ...
... 7. Keep in mind the size of the telescope. Some larger scopes can be over 100 pounds. Often a smaller scope will get used more often because it is easier to move and set up. 8. Newer small computerized “GOTO” style telescopes will automatically position the telescope to an object you select in its i ...
Iron Mineralogy of Venus` Surface Investigated by Mossbauer
... A MB spectrum is the relative number of γ -rays per second reemitted from (back scattering geometry) or absorbed by (transmission geometry) a sample as a function of the relative velocity of the source and sample. Although MB spectra for transmission and backscattering geometry are mirror images (i. ...
... A MB spectrum is the relative number of γ -rays per second reemitted from (back scattering geometry) or absorbed by (transmission geometry) a sample as a function of the relative velocity of the source and sample. Although MB spectra for transmission and backscattering geometry are mirror images (i. ...
Response to Gary Hoge on Whether the Earth can be the Center of
... because they need it to fulfill their Big Bang expanding universe model. Why are these scientists so desperate? Because if they don’t propose “Dark” Energy and Matter, then they will have to go back to pre-Copernican days when we believed the earth was motionless in the center of the universe. What ...
... because they need it to fulfill their Big Bang expanding universe model. Why are these scientists so desperate? Because if they don’t propose “Dark” Energy and Matter, then they will have to go back to pre-Copernican days when we believed the earth was motionless in the center of the universe. What ...
pasta Jos´e A. Pons , Daniele Vigan`o and Nanda Rea
... dissipation of the magnetic field, which in principle predicts that pulsars of longer periods (20100 s) should be visible. In models D and E, the slow release of magnetic energy through Joule heating keeps the neutron star bright and visible much longer than for models A, B and C. The luminosity of ...
... dissipation of the magnetic field, which in principle predicts that pulsars of longer periods (20100 s) should be visible. In models D and E, the slow release of magnetic energy through Joule heating keeps the neutron star bright and visible much longer than for models A, B and C. The luminosity of ...
Anisotropy - IIT Kanpur
... Anisotropy in radio polarizations from distant AGNs Two point correlations in optical polarizations from AGNs ...
... Anisotropy in radio polarizations from distant AGNs Two point correlations in optical polarizations from AGNs ...
File - Mr. Catt`s Class
... spectrograph is a visual record of the spectrum taken by a spectrometer. 5. A spectrometer uses a diffraction grating—a device that uses the wave properties of EM radiation to separate the radiation into its various wavelengths. ...
... spectrograph is a visual record of the spectrum taken by a spectrometer. 5. A spectrometer uses a diffraction grating—a device that uses the wave properties of EM radiation to separate the radiation into its various wavelengths. ...
Presentation in PDF format.
... O stars are always observed close to sites of current or recent star formation. Because of their high luminosities, O stars have very strong stellar winds, observed as asymmetric emission/absorption lines. Material is driven off the star at velocities of several hundred km s-1, with mass-loss rates ...
... O stars are always observed close to sites of current or recent star formation. Because of their high luminosities, O stars have very strong stellar winds, observed as asymmetric emission/absorption lines. Material is driven off the star at velocities of several hundred km s-1, with mass-loss rates ...
arXiv:astro-ph/9712176v1 15 Dec 1997
... the data of the Planetary Camera (PC), which has a scaling of 0.04555”/pixel. The sky values were determined from the Wide Field Camera (WFC) images in areas which were at least 55” away from the galaxy’s center. After sky subtraction the foreground stars and galaxies were either replaced with value ...
... the data of the Planetary Camera (PC), which has a scaling of 0.04555”/pixel. The sky values were determined from the Wide Field Camera (WFC) images in areas which were at least 55” away from the galaxy’s center. After sky subtraction the foreground stars and galaxies were either replaced with value ...
THE RED-SEQUENCE LUMINOSITY FUNCTION IN GALAXY
... single ‘‘monolithic collapse’’ ( Eggen et al. 1962), with stars in elliptical galaxies being formed in a single burst, thereafter ...
... single ‘‘monolithic collapse’’ ( Eggen et al. 1962), with stars in elliptical galaxies being formed in a single burst, thereafter ...
Astronomical spectroscopy
Astronomical spectroscopy is the study of astronomy using the techniques of spectroscopy to measure the spectrum of electromagnetic radiation, including visible light, which radiates from stars and other hot celestial objects. Spectroscopy can be used to derive many properties of distant stars and galaxies, such as their chemical composition, temperature, density, mass, distance, luminosity, and relative motion using Doppler shift measurements.