the comet`s tale - Institute of Astronomy
... Director for 25 years. I think this is enough (perhaps too much), and it is time to start considering a successor, to take up the post at the start of the new BAA year in 2015 October. There is a lot for a Section Director to do, though a new one may choose to delegate many of the tasks, which inclu ...
... Director for 25 years. I think this is enough (perhaps too much), and it is time to start considering a successor, to take up the post at the start of the new BAA year in 2015 October. There is a lot for a Section Director to do, though a new one may choose to delegate many of the tasks, which inclu ...
Famous Comets - Mr. Hill`s Science Website
... into view, he turned his telescope to a group of stars called M70 (a globular cluster). At a similar time, Tom Bopp, an amateur astronomer at a "star party" in Phoenix (a gathering for astronomers to observe the stars together!), was also observing the M70 globular cluster. Both astronomers noticed ...
... into view, he turned his telescope to a group of stars called M70 (a globular cluster). At a similar time, Tom Bopp, an amateur astronomer at a "star party" in Phoenix (a gathering for astronomers to observe the stars together!), was also observing the M70 globular cluster. Both astronomers noticed ...
the mystery of the tunguska fireball
... stripped of their branches, snapped off and scattered like matchsticks pointing away from the direction of the blast. Even after a careful search Kulik found no crater or other evidence of impact. He searched for meteorite fragments but found nothing. As there was no impact crater and no substantial ...
... stripped of their branches, snapped off and scattered like matchsticks pointing away from the direction of the blast. Even after a careful search Kulik found no crater or other evidence of impact. He searched for meteorite fragments but found nothing. As there was no impact crater and no substantial ...
National Aeronautics and Space Administration
... (6-8) Mathematicians often represent things with abstract ideas, such as numbers or perfectly straight lines, and then work with those ideas alone. The "things" from which they abstract can be ideas themselves; for example, a proposition about "all equal-sided triangles" or "all odd numbers". 2C/M1 ...
... (6-8) Mathematicians often represent things with abstract ideas, such as numbers or perfectly straight lines, and then work with those ideas alone. The "things" from which they abstract can be ideas themselves; for example, a proposition about "all equal-sided triangles" or "all odd numbers". 2C/M1 ...
THE DEMOGRAPHICS OF LONG-PERIOD COMETS ABSTRACT
... of our sample due to failed follow-up. This is probably a conservative upper limit: most of these lost objects were most likely either not real to begin with or fastmoving objects only visible for a short window of time. Secondly, some comets might have been inactive at these large heliocentric dist ...
... of our sample due to failed follow-up. This is probably a conservative upper limit: most of these lost objects were most likely either not real to begin with or fastmoving objects only visible for a short window of time. Secondly, some comets might have been inactive at these large heliocentric dist ...
1997 Apparition of Comet Hale-Bopp - HIGP
... Our Solar System was formed approximately 4.55 billion years ago out of a molecular cloud - a large concentration of gas (roughly 75% hydrogen and 21-24% helium with trace amounts of other molecules) and dust grains. In addition to hydrogen (H) and helium (He), the interstellar medium (ISM) gas cons ...
... Our Solar System was formed approximately 4.55 billion years ago out of a molecular cloud - a large concentration of gas (roughly 75% hydrogen and 21-24% helium with trace amounts of other molecules) and dust grains. In addition to hydrogen (H) and helium (He), the interstellar medium (ISM) gas cons ...
ultraviolet radiation in the solar system
... window is always followed by an increase in knowledge of the subject concerned. This is also the case with the subject of this book, ultraviolet radiation (hereafter UV). In principle, the ultraviolet range might be just one more of these windows, of no particular importance. However, the energy per ...
... window is always followed by an increase in knowledge of the subject concerned. This is also the case with the subject of this book, ultraviolet radiation (hereafter UV). In principle, the ultraviolet range might be just one more of these windows, of no particular importance. However, the energy per ...
SPICA Yellow Book
... what kinds of host stars, in which locations in the Galaxy, are the most favourable to the formation of planets” and “Investigate the conditions for star formation and evolution”. SPICA will have a far-IR spectrometer more than an order of magnitude more sensitive than any previous facility, enablin ...
... what kinds of host stars, in which locations in the Galaxy, are the most favourable to the formation of planets” and “Investigate the conditions for star formation and evolution”. SPICA will have a far-IR spectrometer more than an order of magnitude more sensitive than any previous facility, enablin ...
Introduction to Planetary Science
... available to us at the present time. Accordingly, we emphasize the importance of the scientific method in the exploration of the solar system. In addition, we demonstrate the consistency of the physical and chemical properties of the planets and their satellites with the current theory of the origin ...
... available to us at the present time. Accordingly, we emphasize the importance of the scientific method in the exploration of the solar system. In addition, we demonstrate the consistency of the physical and chemical properties of the planets and their satellites with the current theory of the origin ...
The universe of the coming ALMA revolution
... This process continues and diversifies as molecules are liberated from the dust by warming, becoming gaseous in space. Molecules created in these ways may seed young planets with the building blocks of life. ...
... This process continues and diversifies as molecules are liberated from the dust by warming, becoming gaseous in space. Molecules created in these ways may seed young planets with the building blocks of life. ...
Astronomy WHS Sow
... To describe the main features of planets. With the discovery during the latter half of the 20th century of more objects within the Solar System and large objects around other stars, disputes arose over what should constitute a planet. There was particular disagreement over whether an object should b ...
... To describe the main features of planets. With the discovery during the latter half of the 20th century of more objects within the Solar System and large objects around other stars, disputes arose over what should constitute a planet. There was particular disagreement over whether an object should b ...
Document
... in an M star’s habitable zone (0.02–0.2 AU) (Tarter et al. 2007) would be habitable as long as liquid water and the chemical constituents necessary for the emergence of life were present on them for a sufficiently long period of time. Furthermore, Segura et al. (2010) concluded that the flares emitt ...
... in an M star’s habitable zone (0.02–0.2 AU) (Tarter et al. 2007) would be habitable as long as liquid water and the chemical constituents necessary for the emergence of life were present on them for a sufficiently long period of time. Furthermore, Segura et al. (2010) concluded that the flares emitt ...
Worlds Beyond: A Strategy for the Detection and Characterization of
... our calculation between iron-rock planets and gas giants. Transmission spectroscopy of iron-rock planets with NIRSpec using our criteria (R = 100 at 2µm, SNR > 10 per resolution element after observing 10 transits) will be extremely challenging or impossible.1 The results are very sensitive to the v ...
... our calculation between iron-rock planets and gas giants. Transmission spectroscopy of iron-rock planets with NIRSpec using our criteria (R = 100 at 2µm, SNR > 10 per resolution element after observing 10 transits) will be extremely challenging or impossible.1 The results are very sensitive to the v ...
The ALMA Universe - ALMA Observatory
... short-wavelength radiation, such as gamma rays and X-rays, to ultraviolet light, visible light and infrared rays, and finally to long-wavelength electromagnetic waves, such as radio waves. This chart shows that what we see in visible light merely represents a tiny part of the electromagnetic spectru ...
... short-wavelength radiation, such as gamma rays and X-rays, to ultraviolet light, visible light and infrared rays, and finally to long-wavelength electromagnetic waves, such as radio waves. This chart shows that what we see in visible light merely represents a tiny part of the electromagnetic spectru ...
Issue #15 - 2016 April - National Space Society
... US to lack full space launch capability beyond 2019 without Russian engine www.spacedaily.com/reports/US_to_lack_full_space_launch_capability_beyond_2019_Without_Russia n_engine_999.html 28 January, 2016 - Full US space launch capability may be delayed beyond 2019 if it cuts its supply of Russian-ma ...
... US to lack full space launch capability beyond 2019 without Russian engine www.spacedaily.com/reports/US_to_lack_full_space_launch_capability_beyond_2019_Without_Russia n_engine_999.html 28 January, 2016 - Full US space launch capability may be delayed beyond 2019 if it cuts its supply of Russian-ma ...
Rare Earth: Why Complex Life is Uncommon in the Universe
... the discussion spurred by the book often left the realm of scientific discourse, where we’d intended it to take place, and entered the arenas of religion, ethics, and science fiction. Science has progressed since the publication, yet nothing we have read or discovered in the years since has caused u ...
... the discussion spurred by the book often left the realm of scientific discourse, where we’d intended it to take place, and entered the arenas of religion, ethics, and science fiction. Science has progressed since the publication, yet nothing we have read or discovered in the years since has caused u ...
book_text4
... of the mission has far exceeded the most optimistic expectations of all those involved in the planning and execution of the project. When I joined the project in 1977, I had to describe the astronomy programme I would carry out with the Hubble once it was in operation in orbit. Seventeen years later ...
... of the mission has far exceeded the most optimistic expectations of all those involved in the planning and execution of the project. When I joined the project in 1977, I had to describe the astronomy programme I would carry out with the Hubble once it was in operation in orbit. Seventeen years later ...
Debris Disks: Seeing Dust, Thinking of Planetesimals and Planets
... An efficient, and historically the first successful, way of detecting circumstellar dust is the infrared (IR) photometry. If dust is present around a star, it comes to a thermal equilibrium with the stellar radiation. With equilibrium temperatures of dust orbiting a solar-type star at several tens o ...
... An efficient, and historically the first successful, way of detecting circumstellar dust is the infrared (IR) photometry. If dust is present around a star, it comes to a thermal equilibrium with the stellar radiation. With equilibrium temperatures of dust orbiting a solar-type star at several tens o ...
Physics of the Interstellar Medium
... intimately coupled to the physics of the ISM. However, despite its importance, its structure and evolution is still poorly understood. The situation is however improving rapidly. New observations with powerful telescopes have revealed that the ISM is a turbulent, multiphase gas, filled with structur ...
... intimately coupled to the physics of the ISM. However, despite its importance, its structure and evolution is still poorly understood. The situation is however improving rapidly. New observations with powerful telescopes have revealed that the ISM is a turbulent, multiphase gas, filled with structur ...
Volatiles in protoplanetary disks
... a young pre-main sequence star. The gas-rich disk persists during planetesimal and giant planet formation, but not necessarily during the final assembly of terrestrial planets. During the lifetime of a protoplanetary disk, both solidand gas-phase chemistry is active, shaping the initial composition ...
... a young pre-main sequence star. The gas-rich disk persists during planetesimal and giant planet formation, but not necessarily during the final assembly of terrestrial planets. During the lifetime of a protoplanetary disk, both solidand gas-phase chemistry is active, shaping the initial composition ...
Volatiles in protoplanetary disks
... a young pre-main sequence star. The gas-rich disk persists during planetesimal and giant planet formation, but not necessarily during the final assembly of terrestrial planets. During the lifetime of a protoplanetary disk, both solidand gas-phase chemistry is active, shaping the initial composition ...
... a young pre-main sequence star. The gas-rich disk persists during planetesimal and giant planet formation, but not necessarily during the final assembly of terrestrial planets. During the lifetime of a protoplanetary disk, both solidand gas-phase chemistry is active, shaping the initial composition ...
Planet X, Comets and Earth Changes
... There are few people who would have the tenacity to pursue and uphold their beliefs for as long as he has had to do in facing the odds pitted against him over the past decades, and to emerge in tact with as full a commitment as when he started that long ago. His personal philosophy states that he wi ...
... There are few people who would have the tenacity to pursue and uphold their beliefs for as long as he has had to do in facing the odds pitted against him over the past decades, and to emerge in tact with as full a commitment as when he started that long ago. His personal philosophy states that he wi ...
20. Meteorites and the chemical evolution of the Milky Way
... and secondary species. A primary specie is one that can be synthesized in a zero-metallicity star, consisting initially of pure H and He. Examples of primary species are 16O and 12C, both made by stellar He burning. In contrast, nucleosynthesis of a secondary specie requires some preexisting metals ...
... and secondary species. A primary specie is one that can be synthesized in a zero-metallicity star, consisting initially of pure H and He. Examples of primary species are 16O and 12C, both made by stellar He burning. In contrast, nucleosynthesis of a secondary specie requires some preexisting metals ...
1 The Hubble Story (10:56)
... versatility has allowed it to make significant contributions to the field. For example, Hubble’s high resolution has been indispensable in the investigation of the gas and dust disks, dubbed proplyds, around the newly born stars in the Orion Nebula. The proplyds may very well be young planetary syst ...
... versatility has allowed it to make significant contributions to the field. For example, Hubble’s high resolution has been indispensable in the investigation of the gas and dust disks, dubbed proplyds, around the newly born stars in the Orion Nebula. The proplyds may very well be young planetary syst ...
Panspermia
Panspermia (from Greek πᾶν (pan), meaning ""all"", and σπέρμα (sperma), meaning ""seed"") is the hypothesis that life exists throughout the Universe, distributed by meteoroids, asteroids, comets, planetoids and, also, by spacecraft in the form of unintended contamination by microorganisms.Panspermia is a hypothesis proposing that microscopic life forms that can survive the effects of space, such as extremophiles, become trapped in debris that is ejected into space after collisions between planets and small Solar System bodies that harbor life. Some organisms may travel dormant for an extended amount of time before colliding randomly with other planets or intermingling with protoplanetary disks. If met with ideal conditions on a new planet's surfaces, the organisms become active and the process of evolution begins. Panspermia is not meant to address how life began, just the method that may cause its distribution in the Universe.Pseudo-panspermia (sometimes called ""soft panspermia"" or ""molecular panspermia"") argues that the pre-biotic organic building blocks of life originated in space and were incorporated in the solar nebula from which the planets condensed and were further —and continuously— distributed to planetary surfaces where life then emerged (abiogenesis). From the early 1970s it was becoming evident that interstellar dust consisted of a large component of organic molecules. Interstellar molecules are formed by chemical reactions within very sparse interstellar or circumstellar clouds of dust and gas. The dust plays a critical role of shielding the molecules from the ionizing effect of ultraviolet radiation emitted by stars.Several simulations in laboratories and in low Earth orbit suggest that ejection, entry and impact is survivable for some simple organisms.