Vacuum quality is subdivided into ranges according to the
... Deep space is generally much more empty than any artificial vacuum. It may or may not meet the definition of high vacuum above, depending on what region of space and astronomical bodies are being considered. For example, the MFP of interplanetary space is smaller than the size of the solar system, b ...
... Deep space is generally much more empty than any artificial vacuum. It may or may not meet the definition of high vacuum above, depending on what region of space and astronomical bodies are being considered. For example, the MFP of interplanetary space is smaller than the size of the solar system, b ...
3. What are the intrinsic and extrinsic environments of exoplanets?
... particularly examining the distribution of orbital eccentricity and long-term dynamical stability. 3. Can they support life? Not all exoplanets, and perhaps very few, will be able to support life. We will match our assessment of the likely conditions on exoplanets against terrestrial life’s experime ...
... particularly examining the distribution of orbital eccentricity and long-term dynamical stability. 3. Can they support life? Not all exoplanets, and perhaps very few, will be able to support life. We will match our assessment of the likely conditions on exoplanets against terrestrial life’s experime ...
Molecules in Space
... several linked aromatic rings. Pyrene, which has the chemical composition of C16 H10 , is an example of a smaller PAH. Molecules containing up to 50 carbon atoms have been considered. Structures and some properties of ‘standard’ PAHs are given by Clemett et al.(36) It is harder to obtain positive sp ...
... several linked aromatic rings. Pyrene, which has the chemical composition of C16 H10 , is an example of a smaller PAH. Molecules containing up to 50 carbon atoms have been considered. Structures and some properties of ‘standard’ PAHs are given by Clemett et al.(36) It is harder to obtain positive sp ...
The local ISM in three dimensions: kinematics
... The nearby region of space provides an important test of the theoretical models and simulations since short lines of sight to nearby stars through the local interstellar medium (LISM) should contain fewer velocity structures containing a less diverse range of physical properties than longer lines of ...
... The nearby region of space provides an important test of the theoretical models and simulations since short lines of sight to nearby stars through the local interstellar medium (LISM) should contain fewer velocity structures containing a less diverse range of physical properties than longer lines of ...
comets, asteroids
... the Oort cloud after the man who discovered it Jan Oort. The Oort cloud is located 1000 times further away from the Sun than Neptune and Pluto. 27. What keeps the comet in orbit? 28. The Sun’s pulling power which is called gravity. It is the same force that keeps the Earth and other planets circling ...
... the Oort cloud after the man who discovered it Jan Oort. The Oort cloud is located 1000 times further away from the Sun than Neptune and Pluto. 27. What keeps the comet in orbit? 28. The Sun’s pulling power which is called gravity. It is the same force that keeps the Earth and other planets circling ...
Exploring Exploring - MESSENGER Education
... oceans (modern-day replica of an ancient Polynesian voyaging canoe; top left) and over land (a map of the Lewis and Clark expedition over the Louisiana Purchase territory; top right), to exploration of the sky (photograph of the Wright Flyer; bottom right) and space (an artist’s impression of the ME ...
... oceans (modern-day replica of an ancient Polynesian voyaging canoe; top left) and over land (a map of the Lewis and Clark expedition over the Louisiana Purchase territory; top right), to exploration of the sky (photograph of the Wright Flyer; bottom right) and space (an artist’s impression of the ME ...
2_ISM - UCT Astronomy Department
... observing the same (standard) source several time during the night with a wide variety in zenith distances – usually well known for established Observatories. ...
... observing the same (standard) source several time during the night with a wide variety in zenith distances – usually well known for established Observatories. ...
Flagship imaging SAG report
... Objective 10: In dusty systems, detect and measure substructures within dusty debris that can be used to infer the presence of unseen planets. Objective 11: Understand the time evolution of circumstellar disk properties around a wider star sample at greater distances, from early protoplanetary stag ...
... Objective 10: In dusty systems, detect and measure substructures within dusty debris that can be used to infer the presence of unseen planets. Objective 11: Understand the time evolution of circumstellar disk properties around a wider star sample at greater distances, from early protoplanetary stag ...
A Modern View of the Universe
... Astronomical Distance Measurements Notice that Figure 1.1 is labeled with an approximate size for each structure in kilometers. In astronomy, many of the distances are so large that kilometers are not the most convenient unit. Instead, we often use two other units: • One astronomical unit (AU) is ...
... Astronomical Distance Measurements Notice that Figure 1.1 is labeled with an approximate size for each structure in kilometers. In astronomy, many of the distances are so large that kilometers are not the most convenient unit. Instead, we often use two other units: • One astronomical unit (AU) is ...
The absence of CO from the dust peak around ϵ Eri
... Assuming that the gas and dust are thermalized with an equilibrium temperature of 35 K (Dent et al. 2000), the formalism of Knapp et al. (1980) allows the conversion of the observed 3σ upper limit of 0.0156 K km s−1 (in units of T mb now) into a column density of CO molecules of 8.7 × 1011 cm−2 , im ...
... Assuming that the gas and dust are thermalized with an equilibrium temperature of 35 K (Dent et al. 2000), the formalism of Knapp et al. (1980) allows the conversion of the observed 3σ upper limit of 0.0156 K km s−1 (in units of T mb now) into a column density of CO molecules of 8.7 × 1011 cm−2 , im ...
uv surface environment of earth-like planets orbiting
... 300 times less biologically effective radiation, about 2 times modern Earth–Sun levels. The UV fluxes calculated here provide a grid of model UV environments during the evolution of an Earth-like planet orbiting a range of stars. These models can be used as inputs into photo-biological experiments an ...
... 300 times less biologically effective radiation, about 2 times modern Earth–Sun levels. The UV fluxes calculated here provide a grid of model UV environments during the evolution of an Earth-like planet orbiting a range of stars. These models can be used as inputs into photo-biological experiments an ...
Space Exploration
... The purpose of this Learning Unit Pack is to provide you with the resources that will help you cover the material from the curriculum that will be tested on the Final Exam in June. Follow these steps to successfully complete this Unit Learning Pack: Step 1 – Read the Topic Notes Step 2 – Use a highl ...
... The purpose of this Learning Unit Pack is to provide you with the resources that will help you cover the material from the curriculum that will be tested on the Final Exam in June. Follow these steps to successfully complete this Unit Learning Pack: Step 1 – Read the Topic Notes Step 2 – Use a highl ...
A radiogenic heating evolution model for cosmochemically Earth
... of the long-lived isotopes in Earth’s mantle have declined significantly over geologic time. For example, although 235U was 88 times more abundant at the time of Solar System formation (tss = 4.568 Ga; Amelin et al., 2002; Bouvier and Wadhwa, 2010) than it is now, it became effectively extinct in Ear ...
... of the long-lived isotopes in Earth’s mantle have declined significantly over geologic time. For example, although 235U was 88 times more abundant at the time of Solar System formation (tss = 4.568 Ga; Amelin et al., 2002; Bouvier and Wadhwa, 2010) than it is now, it became effectively extinct in Ear ...
The formation of the solar system
... properties from our solar system. Nevertheless the formation of the solar system is still of special interest for several reasons. First, it is only for the solar system that we can directly examine material that is left over from the formation process in the form of meteorites. Second, only for the ...
... properties from our solar system. Nevertheless the formation of the solar system is still of special interest for several reasons. First, it is only for the solar system that we can directly examine material that is left over from the formation process in the form of meteorites. Second, only for the ...
Comets
... more than about 40º to the ecliptic plane (the plane of the Earth’s orbit). As a result, short-period comets travel around the Sun in the same direction that the Earth and other planets do, whereas many long-period comets move in the opposite direction (their inclinations exceed 90º). This differenc ...
... more than about 40º to the ecliptic plane (the plane of the Earth’s orbit). As a result, short-period comets travel around the Sun in the same direction that the Earth and other planets do, whereas many long-period comets move in the opposite direction (their inclinations exceed 90º). This differenc ...
SECTION28.1 Formation of the Solar System
... Gravity and orbits • If it were not for gravity, the Moon would continue to move in a straight line and would not orbit Earth. The same is true of the planets and their moons, stars, and all orbiting bodies throughout the universe. ...
... Gravity and orbits • If it were not for gravity, the Moon would continue to move in a straight line and would not orbit Earth. The same is true of the planets and their moons, stars, and all orbiting bodies throughout the universe. ...
Scientific Evidence for A
... Then God said, “Let the earth bring forth living creatures after their kind: cattle and creeping things and beasts of the earth after their kind”; and it was so. And God made the beasts of the earth after their kind, and the cattle after their kind, and everything that creeps on the ground after its ...
... Then God said, “Let the earth bring forth living creatures after their kind: cattle and creeping things and beasts of the earth after their kind”; and it was so. And God made the beasts of the earth after their kind, and the cattle after their kind, and everything that creeps on the ground after its ...
KEPLER: Search for Earth-Size Planets in the Habitable Zone
... a minimum of three transits. Because the number of planets expected to be detected depends on the number and characteristics of those assumed for the model calculation, the values shown in Figures 4 and 5 are for illustrative purposes only! The sole purpose of the Kepler Mission is to determine thes ...
... a minimum of three transits. Because the number of planets expected to be detected depends on the number and characteristics of those assumed for the model calculation, the values shown in Figures 4 and 5 are for illustrative purposes only! The sole purpose of the Kepler Mission is to determine thes ...
Shouting in the Jungle: the SETI Transmission Debate
... For a single parabolic antenna, the receiver’s 3 dB beamwidth, in radians, equals roughly wavelength divided by diameter [with the two measured in like units]. Given a terrestrial microwave signal at, say, the neutral hydrogen line (wavelength equal to 21 cm), the required receive antenna diameter t ...
... For a single parabolic antenna, the receiver’s 3 dB beamwidth, in radians, equals roughly wavelength divided by diameter [with the two measured in like units]. Given a terrestrial microwave signal at, say, the neutral hydrogen line (wavelength equal to 21 cm), the required receive antenna diameter t ...
PDF
... and its consequences for weather prediction, agriculture, economical activities and so on. Since ancient times, we have used stars as location beacons for our position on Earth and in space. Greek astronomer Hipparchus of Nicaea was able to find out that Earth’s axis was precessing by comparing his ...
... and its consequences for weather prediction, agriculture, economical activities and so on. Since ancient times, we have used stars as location beacons for our position on Earth and in space. Greek astronomer Hipparchus of Nicaea was able to find out that Earth’s axis was precessing by comparing his ...
01_test_bank
... later, we take it out and the distances between raisins are 3 cm. If you lived in one of the raisins and watched the other raisins as the cake expanded, which of the following would you conclude? A) All raisins would be moving away from you at the same speed. B) More distant raisins would be moving ...
... later, we take it out and the distances between raisins are 3 cm. If you lived in one of the raisins and watched the other raisins as the cake expanded, which of the following would you conclude? A) All raisins would be moving away from you at the same speed. B) More distant raisins would be moving ...
8 Comets: Potential Sources of Prebiotic Molecules for the
... in cometary comae that comets may have played a similar role (Oró 1961): “I suggest that one of the important consequences of the interactions of comets with the Earth would be the accumulation on our planet of relatively large amounts of carbon compounds which are known to be transformed spontaneo ...
... in cometary comae that comets may have played a similar role (Oró 1961): “I suggest that one of the important consequences of the interactions of comets with the Earth would be the accumulation on our planet of relatively large amounts of carbon compounds which are known to be transformed spontaneo ...
Reflection #12: The Journey Ends
... The Solar System consists of the Sun, planets, moons, asteroids, meteors, comet, dust, gases and primarily empty space. The Sun is the major source of heat and light for the Solar System. Everything in the Solar System is under the direct influence of the Sun’s gravitational pull, and these objects ...
... The Solar System consists of the Sun, planets, moons, asteroids, meteors, comet, dust, gases and primarily empty space. The Sun is the major source of heat and light for the Solar System. Everything in the Solar System is under the direct influence of the Sun’s gravitational pull, and these objects ...
The Night Sky
... Does the Sun already seem to be setting about as early as it ever will? You're right! We're still about a month away from the winter solstice — but the Sun sets its earliest around December 7th if you're near latitude 40° north, and right now it already sets within only 3 minutes of that time. ...
... Does the Sun already seem to be setting about as early as it ever will? You're right! We're still about a month away from the winter solstice — but the Sun sets its earliest around December 7th if you're near latitude 40° north, and right now it already sets within only 3 minutes of that time. ...
The Sun`s journey through the local interstellar medium: the
... of the Sun has differed substantially from today. Sometime within the past ∼ 130 000 years, and possibly as recent as ∼ 56 000 years ago, the Sun entered the tenuous tepid partially ionized interstellar material now flowing past the Sun. Prior to that, the Sun was in the low density interior of the ...
... of the Sun has differed substantially from today. Sometime within the past ∼ 130 000 years, and possibly as recent as ∼ 56 000 years ago, the Sun entered the tenuous tepid partially ionized interstellar material now flowing past the Sun. Prior to that, the Sun was in the low density interior of the ...
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.