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The star Betelgeuse is about 500 light years away from us. If this star
The star Betelgeuse is about 500 light years away from us. If this star

... d. emitting neutrinos From  Hubble’s law we can deduce that a. the earth and sun will gradually separate b. we are at the center of expansion c. the CRB could tunnel into black holes d. the universe may have a finite age Stars are made mostly of a. carbon, nitrogen and oxygen from big bang nucleosyn ...
Introduction to the sky
Introduction to the sky

Obliquity and precession of the equinoxes The angle ε between the
Obliquity and precession of the equinoxes The angle ε between the

Introduction to the sky
Introduction to the sky

... On a clear, moonless night, far from city lights, the night sky is magnificent. Roughly 2000 stars are visible to the unaided eye. If you know where to look, you can see Mercury, Venus, Mars, Jupiter, Saturn, and even Uranus. Occasionally, a bright comet is visible. On certain nights of the year th ...
The Earth-Moon-Sun System
The Earth-Moon-Sun System

... The sidereal day has a period of 23 hours, 56 minutes, and 4 seconds (measured in solar time), which is almost 4 minutes shorter than the mean solar day This difference results because the direction to distant stars barely changes because of Earth’s slow revolution along ...
The Milky Way Galaxy
The Milky Way Galaxy

... • The Milky Way galaxy is home to 400 billion stars and our own Sun and Solar System. • It is a barred spiral galaxy. • Scientists think the centre of the galaxy contains a super massive black hole. • The Milky Way is full of dust, gas and stars. • The Milky Way, along with everything else, is ...
Earth Science Chap.2 Sect. 2
Earth Science Chap.2 Sect. 2

... fact that the hours of daylight and darkness are equal everywhere on earth on that day. This is due to the fact that the North Pole tilts neither towards or away from the sun. Autumnal Equinox: Marks the beginning of the fall season in the Northern Hemisphere. The sun’s rays strike the earth at 90º ...
How Big is the Solar System?
How Big is the Solar System?

... suddenly larger leap of 95 paces (more than twice as as the total distance walked up till then). This gap marks the boundary between the inner and outer solar systems. The inner solar system contains the four small, hard, "terrestrial" (Earth-like) planet; the outer solar system contains the four la ...
Our Solar System and Beyond
Our Solar System and Beyond

... — The bombardment of newly formed planets by planetesimals may explain the exceptions. — Material torn from Earth’s crust by a giant impact formed the Moon. • When did the planets form? — Radiometric dating indicates that planets formed 4.5 ...
Stellar Evolution
Stellar Evolution

Planets of Our, and Other, Solar Systems
Planets of Our, and Other, Solar Systems

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Solar System Contents

... •  Converts 4 million tons of mass into energy each second ...
Uranus and Neptune are Comparable in Size
Uranus and Neptune are Comparable in Size

... No. Jupiter, Uranus and Neptune also have rings. No. The rings are composed of thin, closely spaced ringlets consisting of particles of ice and ice-coated rocks. ...
Earth in Space and Time (SC.5.E.5.1)
Earth in Space and Time (SC.5.E.5.1)

... Which of the following explains why Sirius can be seen without a telescope? A. Barnard's star is much larger and hotter than Sirius. B. Sirius is much larger and hotter than Barnard's star. C. All stars are the same size, so Sirius must be hotter than Barnard's star. D. All stars are the same temper ...
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gravitation_notes

... of planetary orbits.  Cavendish measured gravitational forces between human-scale objects before 1800. His experiments were later simplified and improved by von Jolly. ...
The Warrumbungle Observer The Warrumbungle Observer
The Warrumbungle Observer The Warrumbungle Observer

... Jupiter is the brightest object excluding the moon in the evening sky this month. It can be found in the constellation Capricorn which looks like the letter ‘D’ in the eastern evening sky. Careful observations of Jupiter’s position each night will show Jupiter moving compared to the other stars in C ...
Science Through Postcard
Science Through Postcard

... It is not uncommon that at the end of a public lecture, I am surrounded by autograph-hunters, mostly students. Rather than oblige them with my signature, I decided to try out an experiment, on such occasions. I asked the typical autograph-aspirant to send me a question on a postcard. The question sh ...
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Document

Catching Andromeda`s Light
Catching Andromeda`s Light

... locations of all the red clouds of gas he and his colleagues could find. He discovered that the gas clouds lined up along spiral arms, indicating that we live in a spiral galaxy. Why do red clouds of gas trace the spiral arms? It’s because spiral arms give birth to stars. The brightest newborn stars ...
Jan 2011 Regents
Jan 2011 Regents

... **W and Y are high tides because it is the moon’s gravitational pull that causes tidal changes. X and Y will experience low tides until those locations rotate into the appropriate positions.(approx 6 hours later)** ...
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Part B

... • Hypernovae - collapse of stars of greater than 30 solar masses which are spinning rapidly. • The black hole forms before star outer layers contract very much. ...
Weighing a Galaxy—11 Nov Ast 207 F2005 Nov-09 • Schedule
Weighing a Galaxy—11 Nov Ast 207 F2005 Nov-09 • Schedule

... • Surprise: Most of neutrons and protons are not in stars. Lots in gas between galaxies. Location of about Ast 207 F2009 50% is not known. ...
03_LectureOutlines
03_LectureOutlines

A Brief History of the Solar System
A Brief History of the Solar System



... offspring and cannot breed with the members of other such groups. The creation of a new species from a pre-existing species – “speciation” as it is called - generally requires thousands of years. Hence, in our entire lifetime we can witness only a tiny part of the speciation process. How is it possi ...
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Rare Earth hypothesis



In planetary astronomy and astrobiology, the Rare Earth Hypothesis argues that the origin of life and the evolution of biological complexity such as sexually reproducing, multicellular organisms on Earth (and, subsequently, human intelligence) required an improbable combination of astrophysical and geological events and circumstances. The hypothesis argues that complex extraterrestrial life is a very improbable phenomenon and likely to be extremely rare. The term ""Rare Earth"" originates from Rare Earth: Why Complex Life Is Uncommon in the Universe (2000), a book by Peter Ward, a geologist and paleontologist, and Donald E. Brownlee, an astronomer and astrobiologist, both faculty members at the University of Washington.An alternative view point was argued by Carl Sagan and Frank Drake, among others. It holds that Earth is a typical rocky planet in a typical planetary system, located in a non-exceptional region of a common barred-spiral galaxy. Given the principle of mediocrity (also called the Copernican principle), it is probable that the universe teems with complex life. Ward and Brownlee argue to the contrary: that planets, planetary systems, and galactic regions that are as friendly to complex life as are the Earth, the Solar System, and our region of the Milky Way are very rare.
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