sachkov_2013 - Putting A Stars into Context
... of line strengths, light and magnetic field with periods ranging from a few days to many years. It is believed that this abnormal chemical composition is limited only to the outer stellar envelopes. Chemical diffusion altered by a global magnetic ...
... of line strengths, light and magnetic field with periods ranging from a few days to many years. It is believed that this abnormal chemical composition is limited only to the outer stellar envelopes. Chemical diffusion altered by a global magnetic ...
Calculating the Age of a Planetary Nebula
... If you get the error message Use x1 zoom, simply click on the x1 button alongside the zoom buttons described above to bring the image back to the original size. The cursor will change shape and an Output window will pop up on the screen. Click at one edge of the main shell and the x,y-coordinates wi ...
... If you get the error message Use x1 zoom, simply click on the x1 button alongside the zoom buttons described above to bring the image back to the original size. The cursor will change shape and an Output window will pop up on the screen. Click at one edge of the main shell and the x,y-coordinates wi ...
Astronomy Part 1 - Malvern Troop 7
... Moon, a planet, an asteroid or meteoroid, or a comet. In your visual display, label each image and include the date and time it was taken. Show all positions on a star chart or map. Show your display at school or at a troop meeting. Explain the changes you observed. 10. List at least three different ...
... Moon, a planet, an asteroid or meteoroid, or a comet. In your visual display, label each image and include the date and time it was taken. Show all positions on a star chart or map. Show your display at school or at a troop meeting. Explain the changes you observed. 10. List at least three different ...
Astronomical Chronicle for September, 2008
... eye object at mag 4.4 and over 4 degrees in size. In comparison, a closed fist at arms length is 5 degrees in size. It’s large!! In binoculars and small telescopes The galaxy is seen only as a blur, a far cry from the photos one sees in magazines. In a little larger scope, one can see two companion ...
... eye object at mag 4.4 and over 4 degrees in size. In comparison, a closed fist at arms length is 5 degrees in size. It’s large!! In binoculars and small telescopes The galaxy is seen only as a blur, a far cry from the photos one sees in magazines. In a little larger scope, one can see two companion ...
Word Document - University of Iowa Astrophysics
... calculations are to be entered on this form and handed to the teaching assistant. However, you need to preserve your results for later in the semester when you will measure angular sizes of other objects, then use known distances to determine their sizes (radii or diameters). An important concept in ...
... calculations are to be entered on this form and handed to the teaching assistant. However, you need to preserve your results for later in the semester when you will measure angular sizes of other objects, then use known distances to determine their sizes (radii or diameters). An important concept in ...
AAO Techniques Workshop (April 2001) 12 Mbytes
... The FOS could obtain spectra of objects that were fainter than those possible with the GHRS and over a much larger wavelength range (ie 115 to 800 nm). It consisted of a `blue’ tube sensitive from 115 to 550 nm and a `red’ tube covering 180 to 800 nm. The detectors were two 512-element Digicon light ...
... The FOS could obtain spectra of objects that were fainter than those possible with the GHRS and over a much larger wavelength range (ie 115 to 800 nm). It consisted of a `blue’ tube sensitive from 115 to 550 nm and a `red’ tube covering 180 to 800 nm. The detectors were two 512-element Digicon light ...
Astronomical Formulae
... Theta = 115.8/D Where Theta is the smallest resolvable angle in " D is the diameter of the objective in mm Theta = 4.56 Arc Seconds / D Where D is the diameter of the objective in inches Atmospheric conditions seldom permit Theta > 0.5". The Dawes Limit is one half the angular diameter of the Airy ( ...
... Theta = 115.8/D Where Theta is the smallest resolvable angle in " D is the diameter of the objective in mm Theta = 4.56 Arc Seconds / D Where D is the diameter of the objective in inches Atmospheric conditions seldom permit Theta > 0.5". The Dawes Limit is one half the angular diameter of the Airy ( ...
ADAS Simple Guide to Telescope Instrumentation and Operation
... works. The telescope objective is represented by a simple convex lens. In truth, modern refractors usually have two lenses that make up the objective, and they may be convex (curved out on both sides) or plano-convex (bulged out on one side, flat on the other). The multiple lens setup is used to com ...
... works. The telescope objective is represented by a simple convex lens. In truth, modern refractors usually have two lenses that make up the objective, and they may be convex (curved out on both sides) or plano-convex (bulged out on one side, flat on the other). The multiple lens setup is used to com ...
NEO lecture 02 - Observations of NEOs
... The camera at ESA’s telescope on Tenerife is cooled by liquid nitrogen to temperatures such that the dark current and its noise contribution can be neglected. The readout is slow enough so that also its noise contribution can be neglected. The camera is operated with a bias of DNbias ~ 8000. For a ...
... The camera at ESA’s telescope on Tenerife is cooled by liquid nitrogen to temperatures such that the dark current and its noise contribution can be neglected. The readout is slow enough so that also its noise contribution can be neglected. The camera is operated with a bias of DNbias ~ 8000. For a ...
... is a member of our Local Group, the Sculptor dwarf, but before you go peering down your nearest large aperture telescope, this galaxy can only be seen in long exposure photographs on very large telescopes. The stars that make up sculptor are relatively faint, with Alpha Sculptor is shining at magnit ...
Preparing astronomical observations and observing with OHP facilities
... Three kinds of observation can be done with OHP facilities: visual observation (looking directly throught the telescope), imaging (the telescope is used without ocular lens but with a filter wheel and a CCD captor) or spectroscopy (no eyepiece, but a spectroscope and a CCD camera). Visual observatio ...
... Three kinds of observation can be done with OHP facilities: visual observation (looking directly throught the telescope), imaging (the telescope is used without ocular lens but with a filter wheel and a CCD captor) or spectroscopy (no eyepiece, but a spectroscope and a CCD camera). Visual observatio ...
The myopia in the Hubble space telescope
... optical surface, the light source cannot be located near the centre of curvature as is traditional in the Foucault and Hartmann tests, the configuration with a hyberboloidal surface would produce spherical aberration, making high precision testing difficult. So the main problem in testing a hyperbol ...
... optical surface, the light source cannot be located near the centre of curvature as is traditional in the Foucault and Hartmann tests, the configuration with a hyberboloidal surface would produce spherical aberration, making high precision testing difficult. So the main problem in testing a hyperbol ...
Why does Sirius twinkle?
... light instead of faraway points of light. The larger disks of light usually aren't distorted; however if you are looking through especially turbulent areas of our atmosphere, and even sometimes when looking at planets that are low in the thicker parts of the atmosphere, they will twinkle. Phil Plait ...
... light instead of faraway points of light. The larger disks of light usually aren't distorted; however if you are looking through especially turbulent areas of our atmosphere, and even sometimes when looking at planets that are low in the thicker parts of the atmosphere, they will twinkle. Phil Plait ...
Extreme Optics and the Search for Earth-Like Planets
... least 20 m. So, based only on wavelength and planet–star angle, one finds that the starshade must be a large distance (R/v < 40,000 km) from the telescope. Conveniently, occulters with diameters of tens of metres can also fully shade the large (up to 10 m in diameter) telescopes suitable for studyin ...
... least 20 m. So, based only on wavelength and planet–star angle, one finds that the starshade must be a large distance (R/v < 40,000 km) from the telescope. Conveniently, occulters with diameters of tens of metres can also fully shade the large (up to 10 m in diameter) telescopes suitable for studyin ...
1” “Sky-Notes” of the Open University Astronomy Club. April 2006. 1
... the polar diameter. The equatorial bulge is due to Jupiter's very rapid rotation of under 10 hours. Even a short observing session of half an hour will show the rapid rotation of surface features. The main cloud belts are easily seen in small telescopes and with increasing aperture and magnification ...
... the polar diameter. The equatorial bulge is due to Jupiter's very rapid rotation of under 10 hours. Even a short observing session of half an hour will show the rapid rotation of surface features. The main cloud belts are easily seen in small telescopes and with increasing aperture and magnification ...
Intro
... bleaching. It is called bleaching because the photopigment color actually becomes almost transparent. In the dark they regenerate and regain ...
... bleaching. It is called bleaching because the photopigment color actually becomes almost transparent. In the dark they regenerate and regain ...
Word doc - UC-HiPACC - University of California, Santa Cruz
... “This was the burst of the century!” exclaimed James A. Wren, an engineer at Los Alamos National Laboratory and co-author of one of the papers. Indeed, GRB 130427A (as it is now called) was the most powerful gamma-ray burst and the second-brightest optical flash measured in 18 years. The supernova d ...
... “This was the burst of the century!” exclaimed James A. Wren, an engineer at Los Alamos National Laboratory and co-author of one of the papers. Indeed, GRB 130427A (as it is now called) was the most powerful gamma-ray burst and the second-brightest optical flash measured in 18 years. The supernova d ...
Optical Infrared Coordination Network for Astronomy FP7 2013
... as part of a classically scheduled operations without flexibility for specific observing constraints. Also known as ‘Delegated visitor mode’. The PI is not expected to provide an observer. Robotic: Automated telescope or network of telescopes using software to schedule and execute observations accor ...
... as part of a classically scheduled operations without flexibility for specific observing constraints. Also known as ‘Delegated visitor mode’. The PI is not expected to provide an observer. Robotic: Automated telescope or network of telescopes using software to schedule and execute observations accor ...
Testing Your Sky
... Observing the stars from under the ocean of earth's air has been said to be analogous to observing birds from the bottom of a swimming pool. In no better way can this be seen to be true than when examining the phenomenon of twinkling. Observer a bright star, especially when it's low in the sky. Can ...
... Observing the stars from under the ocean of earth's air has been said to be analogous to observing birds from the bottom of a swimming pool. In no better way can this be seen to be true than when examining the phenomenon of twinkling. Observer a bright star, especially when it's low in the sky. Can ...
Measuring Radii and Temperatures of Stars
... • To avoid uncertainties in Teff and BC • Determine PV as a function of B-V PV(B-V)=logTeff – 0.1BC PV ( B V ) a b( B V ) c( B V ) 2 d ( B V )3 ...
... • To avoid uncertainties in Teff and BC • Determine PV as a function of B-V PV(B-V)=logTeff – 0.1BC PV ( B V ) a b( B V ) c( B V ) 2 d ( B V )3 ...
Theme 5: The Rise of the Telescope:
... nitions of the stadion, and authorities disagree about which one Eratosthenes used; if instead we scale to his value of 252000 stadia for the Earth’s circumference, we get about 100 Earth radii for the former value (much too small) and about 20000 for the latter (within 20%). It is tempting to cred ...
... nitions of the stadion, and authorities disagree about which one Eratosthenes used; if instead we scale to his value of 252000 stadia for the Earth’s circumference, we get about 100 Earth radii for the former value (much too small) and about 20000 for the latter (within 20%). It is tempting to cred ...
Lecture 6-Spectral resolution, wavelength coverage, the atmosphere
... Data from the William Herschel 4.2 metre Telescope in La Palma. Wavelength 689.3nm, Exposure time 30ms per frame. The data were taken with a simple Speckle Camera situated on the GHRIL platform of the telescope. The data sets were taken with the Speckle Imaging group at Cardiff University. ...
... Data from the William Herschel 4.2 metre Telescope in La Palma. Wavelength 689.3nm, Exposure time 30ms per frame. The data were taken with a simple Speckle Camera situated on the GHRIL platform of the telescope. The data sets were taken with the Speckle Imaging group at Cardiff University. ...
Document
... could only see them as points of light. Unlike the things on the Earth that we can study up close, handle, listen to, smell, and taste, the only thing ancient watchers of the sky had to learn about things in space was their eyes and imaginations. Only very recently in the history of humanity have as ...
... could only see them as points of light. Unlike the things on the Earth that we can study up close, handle, listen to, smell, and taste, the only thing ancient watchers of the sky had to learn about things in space was their eyes and imaginations. Only very recently in the history of humanity have as ...
Spectral resolution, wavelength coverage, the atmosphere and
... Data from the William Herschel 4.2 metre Telescope in La Palma. Wavelength 689.3nm, Exposure time 30ms per frame. The data were taken with a simple Speckle Camera situated on the GHRIL platform of the telescope. The data sets were taken with the Speckle Imaging group at Cardiff University. ...
... Data from the William Herschel 4.2 metre Telescope in La Palma. Wavelength 689.3nm, Exposure time 30ms per frame. The data were taken with a simple Speckle Camera situated on the GHRIL platform of the telescope. The data sets were taken with the Speckle Imaging group at Cardiff University. ...
Astronomical seeing
Astronomical seeing refers to the blurring and twinkling of astronomical objects such as stars caused by turbulent mixing in the Earth's atmosphere varying the optical refractive index. The astronomical seeing conditions on a given night at a given location describe how much the Earth's atmosphere perturbs the images of stars as seen through a telescope.The most common seeing measurement is the diameter (or more correctly the full width at half maximum or FWHM) of the optical intensity across the seeing disc (the point spread function for imaging through the atmosphere). The FWHM of the point spread function (loosely called seeing disc diameter or ""seeing"") is a reference to the best possible angular resolution which can be achieved by an optical telescope in a long photographic exposure, and corresponds to the FWHM of the fuzzy blob seen when observing a point-like source (such as a star) through the atmosphere. The size of the seeing disc is determined by the astronomical seeing conditions at the time of the observation. The best conditions give a seeing disk diameter of ~0.4 arcseconds and are found at high-altitude observatories on small islands such as Mauna Kea or La Palma.Seeing is one of the biggest problems for Earth-based astronomy: while the big telescopes have theoretically milli-arcsecond resolution, the real image will never be better than the average seeing disc during the observation. This can easily mean a factor of 100 between the potential and practical resolution. Starting in the 1990s, new adaptive optics have been introduced that can help correct for these effects, dramatically improving the resolution of ground based telescopes.