Lecture 3
... • Sun plus 8 (or 9 with Pluto) planets many of which have moons • plus “debris”: comets, asteroids, meteors, etc • We’ll go over historical understanding of motion (which is “complicated” when viewed from the Earth) and later look at Solar System formation, planetary atmospheres, and planets discove ...
... • Sun plus 8 (or 9 with Pluto) planets many of which have moons • plus “debris”: comets, asteroids, meteors, etc • We’ll go over historical understanding of motion (which is “complicated” when viewed from the Earth) and later look at Solar System formation, planetary atmospheres, and planets discove ...
2-The Earth in space
... The Inner Planets The inner planets are the smallest and warmest planets. They have hard surfaces made of rock. The inner planets revolve around the sun more quickly than the outer planets do. 1-Mercury is about the size of Earth’s moon Mercury has a thin atmosphere of carbon dioxide with a surface ...
... The Inner Planets The inner planets are the smallest and warmest planets. They have hard surfaces made of rock. The inner planets revolve around the sun more quickly than the outer planets do. 1-Mercury is about the size of Earth’s moon Mercury has a thin atmosphere of carbon dioxide with a surface ...
Article on Pluto (for 1st science news)
... Pluto was discovered in 1930. Because of its size and distance from Earth, astronomers had no idea of its composition or other characteristics at the time. But having no reason to think that many other similar bodies would eventually be found in the outer reaches of the solar system--or that a new ...
... Pluto was discovered in 1930. Because of its size and distance from Earth, astronomers had no idea of its composition or other characteristics at the time. But having no reason to think that many other similar bodies would eventually be found in the outer reaches of the solar system--or that a new ...
What is Pluto?
... What is Pluto? • Strange object; located far out from the Sun with gas giants but small size and very elliptical and highly inclined orbit • Pluto is a mixture of ices and rocks • composition similar to satellites of giant planets • Could be captured Kuiper Belt Object (e.g. comet)? ...
... What is Pluto? • Strange object; located far out from the Sun with gas giants but small size and very elliptical and highly inclined orbit • Pluto is a mixture of ices and rocks • composition similar to satellites of giant planets • Could be captured Kuiper Belt Object (e.g. comet)? ...
solar system form
... much later by stars and are cast into space when stars die. By mass, 98% of the observed matter in the universe is hydrogen and helium. The solar system formed 4.6 billion years ago from a swirling, disk-shaped cloud of gas, ice, and dust, called the solar nebula. The four inner planets formed throu ...
... much later by stars and are cast into space when stars die. By mass, 98% of the observed matter in the universe is hydrogen and helium. The solar system formed 4.6 billion years ago from a swirling, disk-shaped cloud of gas, ice, and dust, called the solar nebula. The four inner planets formed throu ...
Transit surveys for Earths in the habitable zones of white dwarfs
... Nutzman & Charbonneau (2008) to compute the telescope sensitivity, including sky and read noise, and assuming an exposure time of 15 s; I conservatively expanded the error bars an additional 50%. Each white dwarf is given a multi-planet system whose innermost planet is chosen from a log-normal cente ...
... Nutzman & Charbonneau (2008) to compute the telescope sensitivity, including sky and read noise, and assuming an exposure time of 15 s; I conservatively expanded the error bars an additional 50%. Each white dwarf is given a multi-planet system whose innermost planet is chosen from a log-normal cente ...
Powerpoint - BU Imaging Science
... • Biased towards massive planets close to their star – Most known extrasolar planets are heavier than Jupiter, but closer to their Sun than Earth – Massive -> Larger Doppler shift – Close -> Short orbital periods ...
... • Biased towards massive planets close to their star – Most known extrasolar planets are heavier than Jupiter, but closer to their Sun than Earth – Massive -> Larger Doppler shift – Close -> Short orbital periods ...
Habitable Zones around Evolved Stars
... Factors determining the location of the habitable zone in evolved stars • L changes dramatically as a star evolves beyond the main sequence • ap is altered by changing M* or in extreme cases by tidal or gas drag • The albedoratio depends on planetary atmosphere, surface properties, => and the stell ...
... Factors determining the location of the habitable zone in evolved stars • L changes dramatically as a star evolves beyond the main sequence • ap is altered by changing M* or in extreme cases by tidal or gas drag • The albedoratio depends on planetary atmosphere, surface properties, => and the stell ...
Basics of Atmospheres and their Formation
... • Why? Because dust will block all hot radiation and keep the area cool. Your protostar doesn’t like to be bombarded by high energy radiation from nearby stars! • It likes to be inside a nice cold “dust cocoon”, where it can slowly bring together the gas and dust via gravity, and make a star • Cold ...
... • Why? Because dust will block all hot radiation and keep the area cool. Your protostar doesn’t like to be bombarded by high energy radiation from nearby stars! • It likes to be inside a nice cold “dust cocoon”, where it can slowly bring together the gas and dust via gravity, and make a star • Cold ...
Exoplanets
... Humans have always wondered if life exists elsewhere in the universe. Such life could take many forms, including some very different from our own, but because we only have information about Earth-life (carbon-based organisms) we may as well start by looking for life like us. This means we can test n ...
... Humans have always wondered if life exists elsewhere in the universe. Such life could take many forms, including some very different from our own, but because we only have information about Earth-life (carbon-based organisms) we may as well start by looking for life like us. This means we can test n ...
Circumstellar habitable zone
In astronomy and astrobiology, the circumstellar habitable zone (CHZ), or simply the habitable zone, is the region around a star within which planetary-mass objects with sufficient atmospheric pressure can support liquid water at their surfaces. The bounds of the CHZ are calculated using the known requirements of Earth's biosphere, its position in the Solar System and the amount of radiant energy it receives from the Sun. Due to the importance of liquid water to life as it exists on Earth, the nature of the CHZ and the objects within is believed to be instrumental in determining the scope and distribution of Earth-like extraterrestrial life and intelligence.The habitable zone is also called the Goldilocks zone, a metaphor of the children's fairy tale of Goldilocks and the Three Bears, in which a little girl chooses from sets of three items, ignoring the ones that are too extreme (large or small, hot or cold, etc.), and settling on the one in the middle, which is ""just right"".Since the concept was first presented in 1953, stars have been confirmed to possess a CHZ planet, including some systems that consist of multiple CHZ planets. Most such planets, being super-Earths or gas giants, are more massive than Earth, because such planets are easier to detect. On November 4, 2013, astronomers reported, based on Kepler data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of Sun-like stars and red dwarfs in the Milky Way. 11 billion of these may be orbiting Sun-like stars. The nearest such planet may be 12 light-years away, according to the scientists. The CHZ is also of particular interest to the emerging field of habitability of natural satellites, because planetary-mass moons in the CHZ might outnumber planets.In subsequent decades, the CHZ concept began to be challenged as a primary criterion for life. Since the discovery of evidence for extraterrestrial liquid water, substantial quantities of it are now believed to occur outside the circumstellar habitable zone. Sustained by other energy sources, such as tidal heating or radioactive decay or pressurized by other non-atmospheric means, the basic conditions for water-dependent life may be found even in interstellar space, on rogue planets, or their moons. In addition, other circumstellar zones, where non-water solvents favorable to hypothetical life based on alternative biochemistries could exist in liquid form at the surface, have been proposed.