Science Through Postcard
... Q.3 What is meant by the statement "the ozone hole is growing?" Why is it dangerous? What precautions must be taken to control it? There are many different gases in the atmosphere of the Earth, mainly nitrogen, oxygen, and carbon dioxide. But there are also some other gases in smaller quantities. Oz ...
... Q.3 What is meant by the statement "the ozone hole is growing?" Why is it dangerous? What precautions must be taken to control it? There are many different gases in the atmosphere of the Earth, mainly nitrogen, oxygen, and carbon dioxide. But there are also some other gases in smaller quantities. Oz ...
A PCA approach to stellar effective temperatures⋆
... stars in the same library (all wavelengths) is about 3%, whereas the mean difference between two different spectra of the same star in the same library is about 1% (derived from stars observed more than once in Elodie). To select the wavelength regions that we consider in common for both surveys, we a ...
... stars in the same library (all wavelengths) is about 3%, whereas the mean difference between two different spectra of the same star in the same library is about 1% (derived from stars observed more than once in Elodie). To select the wavelength regions that we consider in common for both surveys, we a ...
Tsinghua Center for Astrophysics and the Dark - CPPM
... The Euclid Concept • Named in honour of the pioneer of geometry • Euclid will survey the entire extra-galactic sky (15000 deg2) to simultaneously measure its two principal dark energy probes: – Weak lensing: ...
... The Euclid Concept • Named in honour of the pioneer of geometry • Euclid will survey the entire extra-galactic sky (15000 deg2) to simultaneously measure its two principal dark energy probes: – Weak lensing: ...
Resonant X-ray Emission Spectroscopy
... shallow core-hole in the final state (τ ~ several fs) compared with the intermediate core hole state (τ ~ fs). Since the width of the measured RXES spectrum depends only on the final state lifetime broadening this kind of RXES measurements can be applied to record absorption spectrum free from lifet ...
... shallow core-hole in the final state (τ ~ several fs) compared with the intermediate core hole state (τ ~ fs). Since the width of the measured RXES spectrum depends only on the final state lifetime broadening this kind of RXES measurements can be applied to record absorption spectrum free from lifet ...
Light Rays
... The optical centre is the centre of a lens. Light rays passing through it do not change direction. The principal axis is the line passing through the optical centre and perpendicular to the lens. Rays parallel to the principal axis converge to or diverge from the focus or focal point of a lens. ...
... The optical centre is the centre of a lens. Light rays passing through it do not change direction. The principal axis is the line passing through the optical centre and perpendicular to the lens. Rays parallel to the principal axis converge to or diverge from the focus or focal point of a lens. ...
Total Internal Reflection Spectroscopy for Studying Soft Matter
... of the electric field at the interface due to the overlap of the incident and reflected waves, leading to an increase in sensitivity. This effect is useful even when the surface sensitivity is not necessary, for example in sum-frequency generation where the surface sensitivity is intrinsic to the te ...
... of the electric field at the interface due to the overlap of the incident and reflected waves, leading to an increase in sensitivity. This effect is useful even when the surface sensitivity is not necessary, for example in sum-frequency generation where the surface sensitivity is intrinsic to the te ...
PHYS3380_113015_bw - The University of Texas at Dallas
... Quasars have very large redshifts, indicating by the Hubble law that they are at great distances. • the fact that they are visible at such distances implies they emit enormous amounts of energy and are certainly not stars. Now thought to be AGNs powered by supermassive rotating black holes at their ...
... Quasars have very large redshifts, indicating by the Hubble law that they are at great distances. • the fact that they are visible at such distances implies they emit enormous amounts of energy and are certainly not stars. Now thought to be AGNs powered by supermassive rotating black holes at their ...
PDF only - at www.arxiv.org.
... resolved in the filaments. To estimate the mass for such a thread we scale from the total gas mass of 108 M⊙ inferred from CO emission6 observed in a 22 arcsec IRAM beam on the same Northern filament complex. Assuming that the mass scales with Hα emission, which is the case for the H2 emission measu ...
... resolved in the filaments. To estimate the mass for such a thread we scale from the total gas mass of 108 M⊙ inferred from CO emission6 observed in a 22 arcsec IRAM beam on the same Northern filament complex. Assuming that the mass scales with Hα emission, which is the case for the H2 emission measu ...
Chapter 9 Parallax and Distance to Stars
... distance of 1 AU. The angle p will be small (measured in arcseconds) and is 21 of the total observed angular displacement. Astronomers adopted a new unit of distance, the parsec, to measure stellar distances. If d is in parsecs, then the following equation applies: d= ...
... distance of 1 AU. The angle p will be small (measured in arcseconds) and is 21 of the total observed angular displacement. Astronomers adopted a new unit of distance, the parsec, to measure stellar distances. If d is in parsecs, then the following equation applies: d= ...
Lecture 16: Iron Core Collapse, Neutron Stars, and Nucleosynthesis
... forming an iron core (b) that reaches Chandrasekhar-mass and starts to collapse. The inner part of the core is compressed greater than nuclear density (c), causing infalling material to bounce (d) and form an outward-propagating shock front (red). The shock starts to stall (e), but it is re-invigora ...
... forming an iron core (b) that reaches Chandrasekhar-mass and starts to collapse. The inner part of the core is compressed greater than nuclear density (c), causing infalling material to bounce (d) and form an outward-propagating shock front (red). The shock starts to stall (e), but it is re-invigora ...
Chapter One: Light Dr.Muayyed Jabar Zoory
... An important property of the index of refraction n is that, for a given material, the index varies with the wavelength of the light passing through the material, as Figure 5 shows. This behavior is called dispersion. Because n is a function of wavelength, Snell’s law of refraction indicates that lig ...
... An important property of the index of refraction n is that, for a given material, the index varies with the wavelength of the light passing through the material, as Figure 5 shows. This behavior is called dispersion. Because n is a function of wavelength, Snell’s law of refraction indicates that lig ...
Spectropolarimetry, Biosignatures, and the Search
... • Detecting amino acids directly may be possible at short wavelengths •Real data from Earth Observations is sparse •Modelling of polarisation signal contrast is needed for remote sensing •Spectroscopy will be the main method for initial detection •Polarimetry will add further details about the natur ...
... • Detecting amino acids directly may be possible at short wavelengths •Real data from Earth Observations is sparse •Modelling of polarisation signal contrast is needed for remote sensing •Spectroscopy will be the main method for initial detection •Polarimetry will add further details about the natur ...
Black Holes and the Scientific Process
... realm of mainstream research, chiefly because of two developments: first, the birth and rapid progress of Xray astronomy, and second, the discovery of pulsars, a class of neutron stars which form the highly dense end point in the life cycle of a normal star. The direct evidence of the existence of n ...
... realm of mainstream research, chiefly because of two developments: first, the birth and rapid progress of Xray astronomy, and second, the discovery of pulsars, a class of neutron stars which form the highly dense end point in the life cycle of a normal star. The direct evidence of the existence of n ...
The doubly eclipsing quintuple low
... observed in the region 8250–8320 Å, and are given in Table 1. (These are very close to those found by the cross-correlation method, but with smaller uncertainties.) Fig. 4 shows our results, together with those of Koo et al.: where our observations overlap with theirs (around phases 0.15 and 0.65) t ...
... observed in the region 8250–8320 Å, and are given in Table 1. (These are very close to those found by the cross-correlation method, but with smaller uncertainties.) Fig. 4 shows our results, together with those of Koo et al.: where our observations overlap with theirs (around phases 0.15 and 0.65) t ...
Wonderworld of Space
... Comets have been known since ancient times. There are Chinese records of Comet Halley going back to at least 240 BC. The famous Bayeux Tapestry which commemorates the Norman Conquest of England in 1066, depicts an image of Comet Halley. Comets are sometimes called dirty snowballs. They are an ice-du ...
... Comets have been known since ancient times. There are Chinese records of Comet Halley going back to at least 240 BC. The famous Bayeux Tapestry which commemorates the Norman Conquest of England in 1066, depicts an image of Comet Halley. Comets are sometimes called dirty snowballs. They are an ice-du ...
the astrolabe - IREM Aix
... Front of the astrolabe 1. Matrix or mother: a disc of brass or bronze 10 to 50 cm in diameter which accommodates the various parts of the instrument. 2. Tympanum: an engraved plate that is placed on the mother. Designed for a given latitude, certain astrolabes possess several of these. 3. Spider (or ...
... Front of the astrolabe 1. Matrix or mother: a disc of brass or bronze 10 to 50 cm in diameter which accommodates the various parts of the instrument. 2. Tympanum: an engraved plate that is placed on the mother. Designed for a given latitude, certain astrolabes possess several of these. 3. Spider (or ...
Two-photon ablation with 1278nm laser radiation
... complex optics to deliver the light and when, as is becoming more and more common, short pulses are used, there is an additional wavelength dependence added by the dispersion of the optical system itself [1]. Precise intracellular microsurgery and in-depth penetration of light into tissue are both e ...
... complex optics to deliver the light and when, as is becoming more and more common, short pulses are used, there is an additional wavelength dependence added by the dispersion of the optical system itself [1]. Precise intracellular microsurgery and in-depth penetration of light into tissue are both e ...
Lecture 21: Polarisation of light and other waves
... oscillating, but in such a way that the total is constant and the direction describes a clockwise circle. This is Right-Handed (RH) polarised light. If the V component lags by 90◦ this gives Left Handed (LH) polarised light, with the E field going round anticlockwise. If 45◦ plane polarised light is ...
... oscillating, but in such a way that the total is constant and the direction describes a clockwise circle. This is Right-Handed (RH) polarised light. If the V component lags by 90◦ this gives Left Handed (LH) polarised light, with the E field going round anticlockwise. If 45◦ plane polarised light is ...
CONSTELLATION CEPHEUS, KING OF ETHIOPIA Cepheus is a
... Cepheus is a constellation in the northern sky. It is named after Cepheus, King of Aethiopia in Greek mythology. He was deemed worthy of a place in the sky because he was fourth in descent from the nymph Io, one of the loves of Zeus – and having Zeus as a relative was always an advantage when it cam ...
... Cepheus is a constellation in the northern sky. It is named after Cepheus, King of Aethiopia in Greek mythology. He was deemed worthy of a place in the sky because he was fourth in descent from the nymph Io, one of the loves of Zeus – and having Zeus as a relative was always an advantage when it cam ...
Last Final Review - Steady Server Pages
... What is the estimated age earth and how do we postulate it? A. 13.7 billion yrs, Uranium-Lead dating B. 4.5 billion yrs, Various radiometric dating methods C. 4.5 million yrs, Carbon dating D. 6,000 yrs, Archbishop James Usher ...
... What is the estimated age earth and how do we postulate it? A. 13.7 billion yrs, Uranium-Lead dating B. 4.5 billion yrs, Various radiometric dating methods C. 4.5 million yrs, Carbon dating D. 6,000 yrs, Archbishop James Usher ...
Section2_Coordinates.. - Faculty Web Sites at the University of Virginia
... - they are an angular measurement on the sky, i.e., perpendicular to the line of sight; that’s why they are also called tangential motions/tangential velocities. Units are arcsec/year, or mas/yr (arcsec/century). - largest proper motion known is that of Barnard’s star 10.3”/yr; typical ~ 0.1”/yr - r ...
... - they are an angular measurement on the sky, i.e., perpendicular to the line of sight; that’s why they are also called tangential motions/tangential velocities. Units are arcsec/year, or mas/yr (arcsec/century). - largest proper motion known is that of Barnard’s star 10.3”/yr; typical ~ 0.1”/yr - r ...
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.