Astro 10: Introductory Astronomy
... rest. These become the true planets. Further orbital collisions likely consolidate these into a fewer number of planets now in long-term stable orbits. • But, the key mystery is getting from dust bunnies to ~mile across. How this happens is still not understood. It would seem that collisions would k ...
... rest. These become the true planets. Further orbital collisions likely consolidate these into a fewer number of planets now in long-term stable orbits. • But, the key mystery is getting from dust bunnies to ~mile across. How this happens is still not understood. It would seem that collisions would k ...
STARS AND PLANETS: A NEW SET OF MIDDLE SCHOOL
... the lifetimes of different masses of stars to each other and to the geologic timeline for the Earth. Students then make predictions about what classes of main sequence stars might have planets with interesting (as defined by the students) life forms, assuming the history of life on Earth is typical. ...
... the lifetimes of different masses of stars to each other and to the geologic timeline for the Earth. Students then make predictions about what classes of main sequence stars might have planets with interesting (as defined by the students) life forms, assuming the history of life on Earth is typical. ...
Testing
... another object. B. The gravity of the other object forces the planet to move inward. C. It gains mass from the other object, causing its gravitational pull to become stronger. ...
... another object. B. The gravity of the other object forces the planet to move inward. C. It gains mass from the other object, causing its gravitational pull to become stronger. ...
ph507-16-1exo2
... of planetary radii. SELECTION: Of course, while planets close to their parent stars will preferentially be found, due to their shorter orbital periods and greater likelihood to transit, planetary transits will be detected at all orbital separations. CONFIRMATION: In general, the detection of three s ...
... of planetary radii. SELECTION: Of course, while planets close to their parent stars will preferentially be found, due to their shorter orbital periods and greater likelihood to transit, planetary transits will be detected at all orbital separations. CONFIRMATION: In general, the detection of three s ...
Searching For Planets Beyond Our Solar System - Cosmos
... The comet was approximately 660 million km from the Earth when the picture was taken, on a midJuly collision course with the gas giant planet Jupiter (Courtesy of H.A. Weaver & T.E. Smith of the Space Telescope Science Institute, and NASA). Theories of the development of life are highly uncertain, b ...
... The comet was approximately 660 million km from the Earth when the picture was taken, on a midJuly collision course with the gas giant planet Jupiter (Courtesy of H.A. Weaver & T.E. Smith of the Space Telescope Science Institute, and NASA). Theories of the development of life are highly uncertain, b ...
4P38.pdf
... The results from the “Sun in Time” program suggest that the coronal X-ray-EUV emissions of the young main-sequence Sun were ~100-1000 times stronger than those of the present Sun. Similarly, the transition region and chromospheric FUV-UV emissions of the young Sun are expected to be 20-60 and 10-20 ...
... The results from the “Sun in Time” program suggest that the coronal X-ray-EUV emissions of the young main-sequence Sun were ~100-1000 times stronger than those of the present Sun. Similarly, the transition region and chromospheric FUV-UV emissions of the young Sun are expected to be 20-60 and 10-20 ...
Habitability: Good, Bad and the Ugly
... Luminosity of the Sun • Definition of luminosity (watts/m2) • Sun’s luminosity has been changing: earlier in its evolution, luminosity was only 70% of what it is today (how could temperature be maintained over geological time) • Future for luminosity – Remember star sequence from lab and lecture – ...
... Luminosity of the Sun • Definition of luminosity (watts/m2) • Sun’s luminosity has been changing: earlier in its evolution, luminosity was only 70% of what it is today (how could temperature be maintained over geological time) • Future for luminosity – Remember star sequence from lab and lecture – ...
Habitability of super-Earth planets around main
... LZAMS has doubled. Stars above 2 M⊙ reach the stage at which they leave the main-sequence phase after less than a billion years. If we set a relatively low age limit of, say, 300 million years as a requirement for the development of complex life forms during the phase of slowly increasing stellar lu ...
... LZAMS has doubled. Stars above 2 M⊙ reach the stage at which they leave the main-sequence phase after less than a billion years. If we set a relatively low age limit of, say, 300 million years as a requirement for the development of complex life forms during the phase of slowly increasing stellar lu ...
Light and shadow from distant worlds
... was a startling discovery1. This gas-giant planet of half a Jupiter mass orbits its star at a distance six times closer than the radius of Mercury’s orbit in our own Solar System. The exoplanet, 51 Peg b, was discovered by measuring the line-of-sight (radial) velocity of the star as it orbited the c ...
... was a startling discovery1. This gas-giant planet of half a Jupiter mass orbits its star at a distance six times closer than the radius of Mercury’s orbit in our own Solar System. The exoplanet, 51 Peg b, was discovered by measuring the line-of-sight (radial) velocity of the star as it orbited the c ...
Asynchronous rotation of Earth-mass planets in the habitable zone
... On Earth, this effect is negligible because we are too far away from the Sun, but the atmospheric torque due to thermal tides can be very powerful, as seen on Venus. Indeed, although tidal friction inside the planet is continuously trying to spin it down to a state of synchronous rotation, thermal ...
... On Earth, this effect is negligible because we are too far away from the Sun, but the atmospheric torque due to thermal tides can be very powerful, as seen on Venus. Indeed, although tidal friction inside the planet is continuously trying to spin it down to a state of synchronous rotation, thermal ...
PHYS178 2008 week 11 part-1
... On several occasions during the past years, astronomical images revealed faint objects, seen near much brighter stars. Some of these have been thought to be those of orbiting exoplanets, but after further study, none of them could stand up to the real test. Some turned out to be faint stellar compan ...
... On several occasions during the past years, astronomical images revealed faint objects, seen near much brighter stars. Some of these have been thought to be those of orbiting exoplanets, but after further study, none of them could stand up to the real test. Some turned out to be faint stellar compan ...
DAY AND NIGHT, SEASONS
... any time, however, if it is tilted the northern and southern hemisphere temperatures at any given latitude will still vary. An eccentric orbit may take the exoplanet in and out of the ‘habitable zone’ (where conditions for life are thought to be most favourable) in the course of a year. Life might e ...
... any time, however, if it is tilted the northern and southern hemisphere temperatures at any given latitude will still vary. An eccentric orbit may take the exoplanet in and out of the ‘habitable zone’ (where conditions for life are thought to be most favourable) in the course of a year. Life might e ...
PDF only - at www.arxiv.org.
... Abstract: Recent observations of several planet-hosting M dwarfs ...
... Abstract: Recent observations of several planet-hosting M dwarfs ...
AST 301 Fall 2007 AST 301: Review for Exam 3 This exam covers
... Chapter 15: This chapter is continuous with Chapter 6 because it is concerned with developing a theoretical model that can explain most of the features of our solar system that we read about in Chapter 6. I suggest you try testing your understanding of the material by telling a friend (imaginary or ...
... Chapter 15: This chapter is continuous with Chapter 6 because it is concerned with developing a theoretical model that can explain most of the features of our solar system that we read about in Chapter 6. I suggest you try testing your understanding of the material by telling a friend (imaginary or ...
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.