March 2016
... compressing patterns. From that tiny amount of data, scientists were able to conclude that two black holes, of 36 and 29 solar masses apiece, merged together, emitting 5% of their total mass into gravitational wave energy, via Einstein's E = mc2. During that event, more energy was emitted in gravita ...
... compressing patterns. From that tiny amount of data, scientists were able to conclude that two black holes, of 36 and 29 solar masses apiece, merged together, emitting 5% of their total mass into gravitational wave energy, via Einstein's E = mc2. During that event, more energy was emitted in gravita ...
Early Observers (The Beginnings of Astronomy)
... The ancient people had no history to learn from. Almost everything they knew about the universe came from what they could discover with their own eyes and minds. They thought that the universe was made up of the sun, moon, planets with all the stars somewhere towards the edge of the universe. ...
... The ancient people had no history to learn from. Almost everything they knew about the universe came from what they could discover with their own eyes and minds. They thought that the universe was made up of the sun, moon, planets with all the stars somewhere towards the edge of the universe. ...
Word Pro - Smvocab
... Fixed Stars - those stars and other heavenly bodies that maintain fixed patterns in the sky. Hypothesis - an unproved theory tentatively accepted to explain certain facts. Magnification - the apparent increase in size of an object viewed with a lens. Magnitude - the degree of brightness of a star. M ...
... Fixed Stars - those stars and other heavenly bodies that maintain fixed patterns in the sky. Hypothesis - an unproved theory tentatively accepted to explain certain facts. Magnification - the apparent increase in size of an object viewed with a lens. Magnitude - the degree of brightness of a star. M ...
Studying Variable stars using Small Telescopes Observational
... RS CVn binaries Brightness variation is due to the spots (similar to sunspots) on the surface of stars. As a star with spots rotates, its brightness changes. ...
... RS CVn binaries Brightness variation is due to the spots (similar to sunspots) on the surface of stars. As a star with spots rotates, its brightness changes. ...
25drake3s
... Observing Project Due Friday Project should be neat, organized, labeled and have all questions fully answered Telescope objects: Venus, Uranus, Neptune, Saturn, Moon ...
... Observing Project Due Friday Project should be neat, organized, labeled and have all questions fully answered Telescope objects: Venus, Uranus, Neptune, Saturn, Moon ...
Discovery of the Kuiper Belt
... from the speed, and then estimated the size from the brightness and the distance. We also calculated the number of similar objects to be found if we could continue our survey over the whole sky in the plane of the solar system. By the end of the night, we knew that we had found a solar system object ...
... from the speed, and then estimated the size from the brightness and the distance. We also calculated the number of similar objects to be found if we could continue our survey over the whole sky in the plane of the solar system. By the end of the night, we knew that we had found a solar system object ...
The Night Sky
... Sun and Earth, an event known as a transit. The planet will be seen as a small black dot moving slowly across the face of the Sun. Such an alignment is so rare that it won’t happen again until the year 2117. However, one should never look at the Sun without proper eye protection or serious damage to ...
... Sun and Earth, an event known as a transit. The planet will be seen as a small black dot moving slowly across the face of the Sun. Such an alignment is so rare that it won’t happen again until the year 2117. However, one should never look at the Sun without proper eye protection or serious damage to ...
Astronomy Notes: Deep Space
... Lightyear :out 10 trillion km, (or about 6 trillion miles ) Nearest star to our solar system: Proxima Centauri 4.2 ly (lightyear): (one parsec). Parallax measures the shift of a star compared to background stars. Electromagnetic Spectrum: energy given off in transverse waves. P. 14 ESRT 2. All EME t ...
... Lightyear :out 10 trillion km, (or about 6 trillion miles ) Nearest star to our solar system: Proxima Centauri 4.2 ly (lightyear): (one parsec). Parallax measures the shift of a star compared to background stars. Electromagnetic Spectrum: energy given off in transverse waves. P. 14 ESRT 2. All EME t ...
Measuring colour in astronomy
... Many of the galaxies imaged by SDSS are too far away to make out individual features, so one has to measure the spectrum and colour of a whole galaxy. Since the light from a galaxy is just the sum of all the light from the individual stars of which it is made, its spectrum – and hence its colour – i ...
... Many of the galaxies imaged by SDSS are too far away to make out individual features, so one has to measure the spectrum and colour of a whole galaxy. Since the light from a galaxy is just the sum of all the light from the individual stars of which it is made, its spectrum – and hence its colour – i ...
The Fingerprints of Atoms
... Example: A line that is usually at λ0 = 6563Å is instead seen at λ = 6565Å. What is the object’s speed? Δλ = 2Å, so that Δλ/λ0 = 2/6563 = 3 x 10-4 Using the above formula, v/c = 3 x 10-4. V = (3 x 10-4)c = (3 x 10-4)(3 x 105 km/s) = 90 km/s. Since the wavelength has increased, the object is moving a ...
... Example: A line that is usually at λ0 = 6563Å is instead seen at λ = 6565Å. What is the object’s speed? Δλ = 2Å, so that Δλ/λ0 = 2/6563 = 3 x 10-4 Using the above formula, v/c = 3 x 10-4. V = (3 x 10-4)c = (3 x 10-4)(3 x 105 km/s) = 90 km/s. Since the wavelength has increased, the object is moving a ...
Ancient Mathematics 450 B.C. 400 B.C. 350 B.C. 300 B.C. 250 B.C.
... 385 B.C. – 323 B.C. Student of Plato who built philosophy based on observation, induction of general principles. Theory of causes determined motion and material of celestial objects. Aristarchus of Samos 310 B.C. – 230 B.C. Determined the distance from the earth to the moon and sun (correct method, ...
... 385 B.C. – 323 B.C. Student of Plato who built philosophy based on observation, induction of general principles. Theory of causes determined motion and material of celestial objects. Aristarchus of Samos 310 B.C. – 230 B.C. Determined the distance from the earth to the moon and sun (correct method, ...
January
... Except for the probes that have been sent to the planets, astronomers cannot reach out and touch their experiment, which is the universe itself. One of the key measurements in Astronomy is distance. To measure distances, the astronomer must rely on the light from any object. Distances are then deter ...
... Except for the probes that have been sent to the planets, astronomers cannot reach out and touch their experiment, which is the universe itself. One of the key measurements in Astronomy is distance. To measure distances, the astronomer must rely on the light from any object. Distances are then deter ...
Introduction to the Earth
... Black holes If the star was bigger than 30 times the mass of the sun The left over core becomes so dense that light can’t escape its gravity. Becomes a black hole. Grab any nearby matter and get bigger As matter falls in, it gives off x-rays. That’s how they find them ...
... Black holes If the star was bigger than 30 times the mass of the sun The left over core becomes so dense that light can’t escape its gravity. Becomes a black hole. Grab any nearby matter and get bigger As matter falls in, it gives off x-rays. That’s how they find them ...
Template M73
... millimetre spectrum into a series of ‘windows’ in which ground based astronomical observations are possible. Within these windows the effects of atmospheric water vapour give rise to continuous absorption rising rapidly at higher frequencies. Consequently, millimetre wavelength observatories are gen ...
... millimetre spectrum into a series of ‘windows’ in which ground based astronomical observations are possible. Within these windows the effects of atmospheric water vapour give rise to continuous absorption rising rapidly at higher frequencies. Consequently, millimetre wavelength observatories are gen ...
Supernova Stalking - Susanna Kumlien Reportage
... a so-called Standard Candle. A Standard Candle is an object astronomers can use to measure distances in the universe, taking advantage of its known properties. With its distance from Earth of only some 12 million light years, considered to be “nearby” by cosmological standards, the supernova´s proxi ...
... a so-called Standard Candle. A Standard Candle is an object astronomers can use to measure distances in the universe, taking advantage of its known properties. With its distance from Earth of only some 12 million light years, considered to be “nearby” by cosmological standards, the supernova´s proxi ...
Astronomical Observations (Fall 2004) Final Exam
... count rate is 16 s-1. Assuming that the noise is random and that equal time is spent observing on and off the source, find the total integration time needed to detect a source whose strength is 1% of the background if the criterion for detection is that the signal-to-noise ratio is 3. (10 pts) ...
... count rate is 16 s-1. Assuming that the noise is random and that equal time is spent observing on and off the source, find the total integration time needed to detect a source whose strength is 1% of the background if the criterion for detection is that the signal-to-noise ratio is 3. (10 pts) ...
Observational astronomy
Observational astronomy is a division of the astronomical science that is concerned with recording data, in contrast with theoretical astrophysics, which is mainly concerned with finding out the measurable implications of physical models. It is the practice of observing celestial objects by using telescopes and other astronomical apparatus.As a science, the study of astronomy is somewhat hindered in that direct experiments with the properties of the distant universe are not possible. However, this is partly compensated by the fact that astronomers have a vast number of visible examples of stellar phenomena that can be examined. This allows for observational data to be plotted on graphs, and general trends recorded. Nearby examples of specific phenomena, such as variable stars, can then be used to infer the behavior of more distant representatives. Those distant yardsticks can then be employed to measure other phenomena in that neighborhood, including the distance to a galaxy.Galileo Galilei turned a telescope to the heavens and recorded what he saw. Since that time, observational astronomy has made steady advances with each improvement in telescope technology.A traditional division of observational astronomy is given by the region of the electromagnetic spectrum observed: Optical astronomy is the part of astronomy that uses optical components (mirrors, lenses and solid-state detectors) to observe light from near infrared to near ultraviolet wavelengths. Visible-light astronomy (using wavelengths that can be detected with the eyes, about 400 - 700 nm) falls in the middle of this range. Infrared astronomy deals with the detection and analysis of infrared radiation (this typically refers to wavelengths longer than the detection limit of silicon solid-state detectors, about 1 μm wavelength). The most common tool is the reflecting telescope but with a detector sensitive to infrared wavelengths. Space telescopes are used at certain wavelengths where the atmosphere is opaque, or to eliminate noise (thermal radiation from the atmosphere). Radio astronomy detects radiation of millimetre to dekametre wavelength. The receivers are similar to those used in radio broadcast transmission but much more sensitive. See also Radio telescopes. High-energy astronomy includes X-ray astronomy, gamma-ray astronomy, and extreme UV astronomy, as well as studies of neutrinos and cosmic rays.Optical and radio astronomy can be performed with ground-based observatories, because the atmosphere is relatively transparent at the wavelengths being detected. Observatories are usually located at high altitudes so as to minimise the absorption and distortion caused by the Earth's atmosphere. Some wavelengths of infrared light are heavily absorbed by water vapor, so many infrared observatories are located in dry places at high altitude, or in space.The atmosphere is opaque at the wavelengths used by X-ray astronomy, gamma-ray astronomy, UV astronomy and (except for a few wavelength ""windows"") far infrared astronomy, so observations must be carried out mostly from balloons or space observatories. Powerful gamma rays can, however be detected by the large air showers they produce, and the study of cosmic rays is a rapidly expanding branch of astronomy.For much of the history of observational astronomy, almost all observation was performed in the visual spectrum with optical telescopes. While the Earth's atmosphere is relatively transparent in this portion of the electromagnetic spectrum, most telescope work is still dependent on seeing conditions and air transparency, and is generally restricted to the night time. The seeing conditions depend on the turbulence and thermal variations in the air. Locations that are frequently cloudy or suffer from atmospheric turbulence limit the resolution of observations. Likewise the presence of the full Moon can brighten up the sky with scattered light, hindering observation of faint objects.For observation purposes, the optimal location for an optical telescope is undoubtedly in outer space. There the telescope can make observations without being affected by the atmosphere. However, at present it remains costly to lift telescopes into orbit. Thus the next best locations are certain mountain peaks that have a high number of cloudless days and generally possess good atmospheric conditions (with good seeing conditions). The peaks of the islands of Mauna Kea, Hawaii and La Palma possess these properties, as to a lesser extent do inland sites such as Llano de Chajnantor, Paranal, Cerro Tololo and La Silla in Chile. These observatory locations have attracted an assemblage of powerful telescopes, totalling many billion US dollars of investment.The darkness of the night sky is an important factor in optical astronomy. With the size of cities and human populated areas ever expanding, the amount of artificial light at night has also increased. These artificial lights produce a diffuse background illumination that makes observation of faint astronomical features very difficult without special filters. In a few locations such as the state of Arizona and in the United Kingdom, this has led to campaigns for the reduction of light pollution. The use of hoods around street lights not only improves the amount of light directed toward the ground, but also helps reduce the light directed toward the sky.Atmospheric effects (astronomical seeing) can severely hinder the resolution of a telescope. Without some means of correcting for the blurring effect of the shifting atmosphere, telescopes larger than about 15–20 cm in aperture can not achieve their theoretical resolution at visible wavelengths. As a result, the primary benefit of using very large telescopes has been the improved light-gathering capability, allowing very faint magnitudes to be observed. However the resolution handicap has begun to be overcome by adaptive optics, speckle imaging and interferometric imaging, as well as the use of space telescopes.Astronomers have a number of observational tools that they can use to make measurements of the heavens. For objects that are relatively close to the Sun and Earth, direct and very precise position measurements can be made against a more distant (and thereby nearly stationary) background. Early observations of this nature were used to develop very precise orbital models of the various planets, and to determine their respective masses and gravitational perturbations. Such measurements led to the discovery of the planets Uranus, Neptune, and (indirectly) Pluto. They also resulted in an erroneous assumption of a fictional planet Vulcan within the orbit of Mercury (but the explanation of the precession of Mercury's orbit by Einstein is considered one of the triumphs of his general relativity theory).