Deep Space (PDF: 224k)
... thousands of years for energy produced in the core to make its way to the surface. Most of this time elapses in the “radiative zone,” where light scatters back and forth, but over time makes its way toward the surface. Above the radiative zone is the convective zone, where energy transport becomes a ...
... thousands of years for energy produced in the core to make its way to the surface. Most of this time elapses in the “radiative zone,” where light scatters back and forth, but over time makes its way toward the surface. Above the radiative zone is the convective zone, where energy transport becomes a ...
Basic Observations of the Night Sky
... the sun during the summer. – Austrailia is slightly closer during their summer. ...
... the sun during the summer. – Austrailia is slightly closer during their summer. ...
The Project Gutenberg EBook of History of Astronomy, by George
... acts of fire and flood, of monarchs and mobs, we have found much that has helped to a fuller knowledge of the heavenly motions than was possible without these records. So Hipparchus, about 150 B.C., and Ptolemy a little later, were able to use the observations of Chaldæan astrologers, as well as tho ...
... acts of fire and flood, of monarchs and mobs, we have found much that has helped to a fuller knowledge of the heavenly motions than was possible without these records. So Hipparchus, about 150 B.C., and Ptolemy a little later, were able to use the observations of Chaldæan astrologers, as well as tho ...
The Missing Mass
... • The orbits in spiral galaxies are not quite circles – they are ellipses. These ellipses are slightly tilted with respect to each other. ...
... • The orbits in spiral galaxies are not quite circles – they are ellipses. These ellipses are slightly tilted with respect to each other. ...
THE UNIVERSE - - GRADE 9, UNIT 4 (4 weeks)
... distance from the Earth. Students use a spectroscope to examine light coming through a spectrum to discover where the red light is. When the red light is very wide, the galaxy is moving away from Earth. Students read article on Red Shift - - “Why is the Sky Dark at Night?” to determine the relations ...
... distance from the Earth. Students use a spectroscope to examine light coming through a spectrum to discover where the red light is. When the red light is very wide, the galaxy is moving away from Earth. Students read article on Red Shift - - “Why is the Sky Dark at Night?” to determine the relations ...
3 Exam #1
... 26. Why do we believe that the core of the Moon is very small? 27. How do we know that most of the Moon’s craters formed very early in its history? 28. Why are all the maria on the side of the Moon that faces Earth? 29. Describe the processes which occur during the formation of a crater. 30. Explai ...
... 26. Why do we believe that the core of the Moon is very small? 27. How do we know that most of the Moon’s craters formed very early in its history? 28. Why are all the maria on the side of the Moon that faces Earth? 29. Describe the processes which occur during the formation of a crater. 30. Explai ...
File - Ms. D. Science CGPA
... Why should anyone think that Earth moves around the sun? After all, on a clear day you can see the sun move across the sky. But Polish astronomer Nicolaus Copernicus realized that an object revolving around you from left to right looks the same as an object standing still while you rotate from right ...
... Why should anyone think that Earth moves around the sun? After all, on a clear day you can see the sun move across the sky. But Polish astronomer Nicolaus Copernicus realized that an object revolving around you from left to right looks the same as an object standing still while you rotate from right ...
Science Olympiad Astronomy C Division Event Golden Gate
... 5. Order images 3, 7, 14, 18, 23 from largest to smallest in physical size. 6. Refer to Image 29 (for locations use letter that best represents the object asked about): What is the name of this diagram? a. Where (what letter A – O) is the bright object in image 1? b. Where (what letter A – O) is the ...
... 5. Order images 3, 7, 14, 18, 23 from largest to smallest in physical size. 6. Refer to Image 29 (for locations use letter that best represents the object asked about): What is the name of this diagram? a. Where (what letter A – O) is the bright object in image 1? b. Where (what letter A – O) is the ...
2. Stellar Physics
... enormous: e.g. Sun’s nearest stellar companion is Proxima Centauri at d = 1.3 pc. Ratio of Solar radius to this distance is: ...
... enormous: e.g. Sun’s nearest stellar companion is Proxima Centauri at d = 1.3 pc. Ratio of Solar radius to this distance is: ...
Name - MIT
... The age of the solar system The age of the universe. The time it takes for half of a surface to become saturated with craters The time it takes for a P-wave to travel to the other side of the Earth The time required for half the nuclei in a sample of a specific isotopic species to undergo radioactiv ...
... The age of the solar system The age of the universe. The time it takes for half of a surface to become saturated with craters The time it takes for a P-wave to travel to the other side of the Earth The time required for half the nuclei in a sample of a specific isotopic species to undergo radioactiv ...
Name - MIT
... E) CO2 11) The two most abundant elements in Saturn are … A) hydrogen and helium. B) iron and hydrogen. C) nitrogen and hydrogen. D) oxygen and carbon. E) nitrogen and oxygen. 12) What are “Hot Jupiters”? A) B) C) D) E) ...
... E) CO2 11) The two most abundant elements in Saturn are … A) hydrogen and helium. B) iron and hydrogen. C) nitrogen and hydrogen. D) oxygen and carbon. E) nitrogen and oxygen. 12) What are “Hot Jupiters”? A) B) C) D) E) ...
General Astronomy - Stockton University
... By 1985, when van de Kamp published a final paper on his discovery, other astronomers, using different telescopes, could not find the distinctive wobble. One went so far as to suggest that the wobble was in the Sproul Telescope rather than in the star. Others claimed they detected a wobble, but not ...
... By 1985, when van de Kamp published a final paper on his discovery, other astronomers, using different telescopes, could not find the distinctive wobble. One went so far as to suggest that the wobble was in the Sproul Telescope rather than in the star. Others claimed they detected a wobble, but not ...
Evolution of a Protostar
... A protostar looks starlike after the surrounding gas is blown away, but its thermal energy comes from gravitational contraction, not fusion. ...
... A protostar looks starlike after the surrounding gas is blown away, but its thermal energy comes from gravitational contraction, not fusion. ...
Theories of Cosmic Evolution - DigitalCommons@University of
... that the planets do so move. And it remained for Newton to show, seventy years later, by a simple geometrical demonstration, that if bodies attract each other inversely as the square of the distance, then Kepler's laws would necessarily be true. And so we reach the summit of the long hill; in this s ...
... that the planets do so move. And it remained for Newton to show, seventy years later, by a simple geometrical demonstration, that if bodies attract each other inversely as the square of the distance, then Kepler's laws would necessarily be true. And so we reach the summit of the long hill; in this s ...
Chandra Emission Line Diagnostics of Sco
... laboratory values. The redshifts indicate they are moving away from us, perhaps being emitted from clumps of material falling back towards the star’s surface. ...
... laboratory values. The redshifts indicate they are moving away from us, perhaps being emitted from clumps of material falling back towards the star’s surface. ...
The Development Of Astronomy
... measurements was not great enough to detect. (It is now known that the stars are indeed very far away and telescopes must be used to detect the small parallactic shifts.) 3. Rotating Earth – Copernicus found it esthetically pleasing to have a rotating Earth (diurnal motion) rather than the distant s ...
... measurements was not great enough to detect. (It is now known that the stars are indeed very far away and telescopes must be used to detect the small parallactic shifts.) 3. Rotating Earth – Copernicus found it esthetically pleasing to have a rotating Earth (diurnal motion) rather than the distant s ...
Kepler, Newton, and laws of motion
... Empirical, based on observations; NOT a theory (in the sense of Newton’s laws). So they are “laws” in the sense of formulas that express some regularity or correlation, but they don’t explain the observed phenomena in terms of something more basic (e.g. laws of motion, gravity--that waited for Newto ...
... Empirical, based on observations; NOT a theory (in the sense of Newton’s laws). So they are “laws” in the sense of formulas that express some regularity or correlation, but they don’t explain the observed phenomena in terms of something more basic (e.g. laws of motion, gravity--that waited for Newto ...
Matariki-Maori New Year
... • If the stars were clear and bright, it was a sign of a favourable and productive season ahead, and planting would begin in September. • If the stars appeared hazy and closely bunched together, a cold winter was in store and planting was put off until October. ...
... • If the stars were clear and bright, it was a sign of a favourable and productive season ahead, and planting would begin in September. • If the stars appeared hazy and closely bunched together, a cold winter was in store and planting was put off until October. ...
History of astronomy
... were closer than 3438 Astronomical Units, Tycho should have been able to measure their trigonometric parallaxes. But he found no parallax for the stars. He then had to make one of two conclusions: 1) the stars were many thousands or even millions of AU away; or 2) the Earth was immobile and did not ...
... were closer than 3438 Astronomical Units, Tycho should have been able to measure their trigonometric parallaxes. But he found no parallax for the stars. He then had to make one of two conclusions: 1) the stars were many thousands or even millions of AU away; or 2) the Earth was immobile and did not ...
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).