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New light on our Sun`s fate - Space Telescope Science Institute
New light on our Sun`s fate - Space Telescope Science Institute

... also determines its brightness and temperature. We now summarize all stages of stellar evolution on this important diagram. Today, astronomers use powerful telescopes, on the ground and in space, to measure stars’ brightnesses, colors, and positions. For example, the Hubble Space Telescope can obser ...
The Planets - Guild of Students
The Planets - Guild of Students

... Saturn is about 75% hydrogen and 25% helium with traces of water, methane, ammonia and "rock", similar to the composition of the primordial Solar Nebula from which the solar system was formed. Saturn's consists of a rocky core, a liquid metallic hydrogen layer and a molecular hydrogen layer; this is ...
ASTR 300 Stars and Stellar Systems Spring 2011
ASTR 300 Stars and Stellar Systems Spring 2011

... Astronomers had found that pulsars slow down with age as the pulsar wind carries angular momentum and energy away. Thus a very rapidly spinning pulsar was assumed to be very young. Later they realized that an old, slowly spinning pulsar could be “spun up” by mass transfer from a companion star. 4. W ...
10438 starlight - The Described and Captioned Media Program
10438 starlight - The Described and Captioned Media Program

... In this program, viewers examine how our basic knowledge about stars has been gained from studying the light we receive from stars. The study of starlight not only reveals straightforward information like the varying brightness of stars, but it also shows other details, such as their spectra, intens ...
Lecture 10 - Lick Observatory
Lecture 10 - Lick Observatory

... Now drop the rocks on the moon. Is the acceleration of the rocks larger or smaller than it was on earth? smaller Do the rocks fall faster or slower than they ...
Is there life outside of Earth? Activity 2: Moving Stars and Their Planets
Is there life outside of Earth? Activity 2: Moving Stars and Their Planets

... Q. Explain what influenced your certainty rating in the last question. A. Student answers will vary. Answers should include reference to the possibility of many combinations that result in the same graph. Page 5: Limitations of Noise Q. Does this graph show a planet orbiting a star? What is your pre ...
Primordial Planet Formation - University of California San Diego
Primordial Planet Formation - University of California San Diego

... sections
for
collisions
with
implications
for
changes
in
their
collisional
dynamics,
 increasing
diffusion
of
the
PGC
planet
clouds
from
the
galaxy
central
core
to
form
 the
galaxy
dark
matter
halo.

With
suddenly
smaller
atmospheres
there
would
be
 fewer
planet
collisions
and
Ofek
et
al.
(2010)
eve ...
ppt
ppt

... – The Sun and the other bodies orbit around a common center of mass – The Sun is so massive that it is very close to the center of mass and moves very little – Orbits are elliptical, but very slightly so ...
University of Alaska Southeast Integrated Unit: The Solar System
University of Alaska Southeast Integrated Unit: The Solar System

... seemed to stay in the same formation. These were the stars. However, other lights seem to move around the sky, wandering in and out and among each other. They named these bodies planetes, which meant, "wandering stars." From this word comes our term, planet, which means a large space object orbiting ...
Exoplanets
Exoplanets

... An astronomer can determine much about a distant star by recording its spectrum. As the star moves in the small orbit resulting from the pull of the exoplanet, it will move towards the Earth and then away as it completes an orbit. The velocity of the star along the line of sight of an observer on Ea ...
May 2016 - Newbury Astronomical Society
May 2016 - Newbury Astronomical Society

... Diagram showing how topography can affect seeing conditions There are many factors that affect the quality of the So what exactly is atmospheric seeing? It is fluctuations image when looking through a telescope. The quality of of the atmosphere and the mixing of air ‘parcels’ of the optics of the te ...
Chap. 02
Chap. 02

... luminosity and high surface temperature) to bottom-right (low luminosity and low surface temperature) – 90% stars in this band – The Sun is one of main sequence stars – Hydrogen burning as energy source ...
Answers
Answers

... stars with different starting masses. ☆ Select a different starting mass for your star in the ‘Star Properties’ banner. ☆ Use the Hertzsprung-Russell diagram tab, click play to watch your new stars evolution. ☆ Try out a few different masses then answer the following questions. 1. Using the Hertzspr ...
Chapter 13
Chapter 13

... E) Both B and C are correct. 22. Which statement about gamma ray bursters is not correct? A) In seconds, they radiate hundreds of times more energy than even supernovae do. B) They seem to be coming from far beyond our own Milky Way. C) They are scaled up X-ray bursters, with more massive objects in ...
Helium Fusion What Will Happen When There Is No More Helium in
Helium Fusion What Will Happen When There Is No More Helium in

... •  Early stages after main sequence –  Similar to a low mass star, but happen much faster •  No helium flash ...
How we know the Earth moves - Michael Beeson
How we know the Earth moves - Michael Beeson

... all the “fixed stars” are at the same distance from Earth. (This was not yet realized at the time of Galileo.) To observe and measure the stellar parallax, one needs good optical instruments, because the effect is very small. In fact, the effort to measure the stellar parallax and so verify Copernic ...
2008F-ExtraSolarPlanets-Smith
2008F-ExtraSolarPlanets-Smith

... varied the mass of the planet to range from 1/300th the mass of Jupiter to ten times the mass of Jupiter. The data shows that fainter stars can be seen with planets of smaller mass. Analyzing this information using the center of mass and Kepler’s Law shows why this is true. As the mass of the planet ...
Mercury`s Orbit
Mercury`s Orbit

... Its  surface  resembles  the  Moon  more  than  it  does      any  terrestrial  planet.  Indeed,  aside  from  cratering      impacts,  the  principal  source  of  surface  modificaGon    for  both  objects  for  ages  has  been ...
Astronomy Unit BM study guide
Astronomy Unit BM study guide

... The Earth’s axis remains pointed in the same direction at all times as the Earth revolves around the Sun. The combination of the revolution around the Sun and the fixed angle of the Earth’s axis result in the following seasonal changes: temperature changes, angle of sunlight, number of daylight hour ...
Star in a Box
Star in a Box

... The luminosity of a star is powered by nuclear fusion taking place in the centre of the star converting hydrogen into helium. – The temperature and density must be high enough to allow nuclear fusion to occur. – Stars are primarily composed of hydrogen, with small amounts of helium. ...
MagdaStavinschi_bothtalks
MagdaStavinschi_bothtalks

... in longitude & in obliquity. They are elliptical. They can also be represented as the sum of two circular nutations with the same period but different amplitudes & directions (one prograde, one retrograde). ...
Astronomer Notes PowerPoint
Astronomer Notes PowerPoint

... over equal areas in equal amounts of time causing it to travel more rapidly in areas closer to the sun. The square of the orbital period is proportional to the cube of its distance from the sun. ...
Training Manual - The Darwin Initiative
Training Manual - The Darwin Initiative

... radically different from those of the other planets, having been altered by the presence of life to contain 21% free oxygen. It has one natural satellite, the Moon the only large satellite of a terrestrial planet in the Solar System. Mars Mars is smaller than Earth and Venus. It possesses an atmosp ...
Introduction to Astronomy
Introduction to Astronomy

... – Just an expanding cloud of heavy elements (C, O, Si, Ni, Co, Fe, etc) ...
Characteristics of Main Sequence Stars
Characteristics of Main Sequence Stars

... • In high mass stars, the CNO nuclear reactions are highly concentrated in the center of the star. As a result, the molecular weight is unchanged over most of the star, and only the core contracts. The star therefore becomes redder, as the increase in the radius overwhelms that of the luminosity. Fo ...
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Planetary habitability



Planetary habitability is the measure of a planet's or a natural satellite's potential to develop and sustain life. Life may develop directly on a planet or satellite or be transferred to it from another body, a theoretical process known as panspermia. As the existence of life beyond Earth is unknown, planetary habitability is largely an extrapolation of conditions on Earth and the characteristics of the Sun and Solar System which appear favourable to life's flourishing—in particular those factors that have sustained complex, multicellular organisms and not just simpler, unicellular creatures. Research and theory in this regard is a component of planetary science and the emerging discipline of astrobiology.An absolute requirement for life is an energy source, and the notion of planetary habitability implies that many other geophysical, geochemical, and astrophysical criteria must be met before an astronomical body can support life. In its astrobiology roadmap, NASA has defined the principal habitability criteria as ""extended regions of liquid water, conditions favourable for the assembly of complex organic molecules, and energy sources to sustain metabolism.""In determining the habitability potential of a body, studies focus on its bulk composition, orbital properties, atmosphere, and potential chemical interactions. Stellar characteristics of importance include mass and luminosity, stable variability, and high metallicity. Rocky, terrestrial-type planets and moons with the potential for Earth-like chemistry are a primary focus of astrobiological research, although more speculative habitability theories occasionally examine alternative biochemistries and other types of astronomical bodies.The idea that planets beyond Earth might host life is an ancient one, though historically it was framed by philosophy as much as physical science. The late 20th century saw two breakthroughs in the field. The observation and robotic spacecraft exploration of other planets and moons within the Solar System has provided critical information on defining habitability criteria and allowed for substantial geophysical comparisons between the Earth and other bodies. The discovery of extrasolar planets, beginning in the early 1990s and accelerating thereafter, has provided further information for the study of possible extraterrestrial life. These findings confirm that the Sun is not unique among stars in hosting planets and expands the habitability research horizon beyond the Solar System.The chemistry of life may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the Universe was only 10–17 million years old. According to the panspermia hypothesis, microscopic life—distributed by meteoroids, asteroids and other small Solar System bodies—may exist throughout the universe. Nonetheless, Earth is the only place in the universe known to harbor life. Estimates of habitable zones around other stars, along with the discovery of hundreds of extrasolar planets and new insights into the extreme habitats here on Earth, suggest that there may be many more habitable places in the universe than considered possible until very recently. On 4 November 2013, astronomers reported, based on Kepler space mission 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 within the Milky Way. 11 billion of these estimated planets may be orbiting Sun-like stars. The nearest such planet may be 12 light-years away, according to the scientists.
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