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Planets - Zoom Astronomy

Planets - Zoom Astronomy
Advertisement. is a user-supported site. As a bonus, site members have access to a banner-ad-free version of the site, with print-friendly pages.Click here to learn more. (Already a member? The Planets (plus the Dwarf Planet Pluto) Our solar system consists of the sun, eight planets, moons, many dwarf planets (or plutoids), an asteroid belt, comets, meteors, and others. The eight planets that orbit the sun are (in order from the sun): Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. Easy ways to remember the order of the planets (plus Pluto) are the mnemonics: "My Very Excellent Mother Just Sent Us Nine Pizzas" and "My Very Easy Method Just Simplifies Us Naming Planets" The first letter of each of these words represents a planet - in the correct order. The largest planet is Jupiter. The inner planets are: Mercury, Venus, Earth, and Mars. Generally, the farther from the Sun, the cooler the planet. Density of the Planets The Earth is the densest planet. Related:  0006 Understand Earth in the solar system and universe.

The Earth/Moon System .br 1) Use checkboxes (Seconds, Minutes, etc) to choose time interval. "Hours" and "Days" work best for animation. Use slidebar at right to control simulation speed. There are 7 speeds, 3 forward (right), 3 reverse (left) and one neutral (center). The bar is initially set at the slowest forward speed. 2) In top panel, Moon (dark or light gray, depending on phase) and Sun (yellow) are shown 4x too large. 3) Eclipse times are estimates only (good to within a few minutes). 4) Distances and sizes are not to scale 5) There is still a problem with the local time - it does not take into account the shift to/from Daylight Savings Time, and so may be off by an hour.

: Planets Planets: The planet count in our solar system has gone as high as 15 before new discoveries prompted a fine tuning of the definition of a planet. The most recent change was in 2006 when scientists reclassified Pluto as a new kind of object - a dwarf planet. Dwarf Planets: This new class of worlds helps us categorize objects that orbit the Sun but aren't quite the same as the rocky planets and gas giants in our solar system. Moons: This count includes only the moons orbiting the eight planets in our solar system. Asteroids: New asteroids are discovered on an almost daily basis. Comets: Orbiting spacecraft such as SOHO have raised this tally in recent years by catching the comets as they plunge toward the Sun - and sometimes vaporize.

What Is a Planet? While many people can point to a picture of Jupiter or Saturn and call it a "planet," the definition of this word is much more subtle and has changed over time. Many astronomers decided on a new definition in 2006 after the discovery of several worlds at the fringes of the solar system — a decision that remains controversial. The International Astronomical Union defined a planet as an object that: orbits the sun has sufficient mass to be round, or nearly round is not a satellite (moon) of another object has removed debris and small objects from the area around its orbit The IAU also created a new classification, "dwarf planet," which is an object that meets planetary criteria except that it has not cleared debris from its orbital neighborhood. This definition meant that Pluto — considered a planet at the time — was demoted and reclassified as a dwarf planet. Planetary history The term "planet" originally comes from the Greek word for "wanderer." Discovery of more worlds

Top 10 Facts About Space Food Space may be the final frontier, but it is also one hell of a restaurant. Over the the past half-century, scientists and space engineers have not only been racing to get their rockets safely outside the Earth’s atmosphere, they’ve been working to ensure the menu keeps their astronauts coming back for more. While there have been all sorts of innovations and improvements, it seems now the options are better than ever, to where we might consider studying rocket science just to gain access to NASA’s kitchen. While these days it seems there is little hope in revisiting space any time soon, here are ten facts about space food, to give us food for thought as we wait until we can become weightless once more. Fact: Early Space Food Was Weird. When Yuri Gagarin become the first human being to go into outer space, he also become the first to eat and do whatever else a human must as a necessary condition of survival. Fact: Regular Foods are Eaten in Space Now. Fact: Jerky is Huge in Space.

The Nine Planets Solar System Tour Phases of the Moon and Percent of the Moon Illuminated Copyright Antonio Cidadao. Used by permission. Click on picture to see large version. From any location on the Earth, the Moon appears to be a circular disk which, at any specific time, is illuminated to some degree by direct sunlight. New Moon - The Moon's unilluminated side is facing the Earth. Waxing Crescent - The Moon appears to be partly but less than one-half illuminated by direct sunlight. First Quarter - One-half of the Moon appears to be illuminated by direct sunlight. Waxing Gibbous - The Moon appears to be more than one-half but not fully illuminated by direct sunlight. Full Moon - The Moon's illuminated side is facing the Earth. Waning Gibbous - The Moon appears to be more than one-half but not fully illuminated by direct sunlight. Last Quarter - One-half of the Moon appears to be illuminated by direct sunlight. Waning Crescent - The Moon appears to be partly but less than one-half illuminated by direct sunlight. Lunation Movie Copyright Antonio Cidadao.

Planet The planets were thought by Ptolemy to orbit Earth in deferent and epicycle motions. Although the idea that the planets orbited the Sun had been suggested many times, it was not until the 17th century that this view was supported by evidence from the first telescopic astronomical observations, performed by Galileo Galilei. By careful analysis of the observation data, Johannes Kepler found the planets' orbits were not circular but elliptical. History Printed rendition of a geocentric cosmological model from Cosmographia, Antwerp, 1539 The idea of planets has evolved over its history, from the divine wandering stars of antiquity to the earthly objects of the scientific age. The five classical planets, being visible to the naked eye, have been known since ancient times and have had a significant impact on mythology, religious cosmology, and ancient astronomy. Babylon Greco-Roman astronomy The ancient Greeks initially did not attach as much significance to the planets as the Babylonians. India

The Moon - Zoom Astronomy The moon is Earth's only natural satellite. The moon is a cold, dry orb whose surface is studded with craters and strewn with rocks and dust (called regolith). The moon has no atmosphere. Recent lunar missions indicate that there might be some frozen ice at the poles. The same side of the moon always faces the Earth. If you were standing on the moon, the sky would always appear dark, even during the daytime. The moon is about 238,900 miles (384,000 km) from Earth on average. The moon revolves around the Earth in about one month (27 days 8 hours). The Moon's orbit is expanding over time as it slows down (the Earth is also slowing down as it loses energy). SAROS The saros is the roughly 18-year periodic cycle of the Earth-Moon-Sun system. The moon's diameter is 2,159 miles (3,474 km), 27% of the diameter of the Earth (a bit over a quarter of the Earth's diameter). The moon's mass is (7.35 x 10 22 kg), about 1/81 of the Earth's mass. The moon's density is 3340 kg/m 3. MOON OR DOUBLE PLANET?

Top 10 Cool Facts about Space Space There is still so little known about outer space by modern science, but of that little we do know, there are some extraordinarily amazing things. This is a list of the top 10 cool facts about Space. 10. Lightweight Fact: If you put Saturn in water it would float The density of Saturn is so low that if you were to put it in a giant glass of water it would float. 9. Fact: We are moving through space at the rate of 530km a second Our Galaxy – the Milky Way is spinning at a rate of 225 kilometers per second. 8. Fact: The moon is drifting away from Earth Every year the moon moves about 3.8cm further away from the Earth. 7. Fact: The light hitting the earth right now is 30 thousand years old The energy in the sunlight we see today started out in the core of the Sun 30,000 years ago – it spent most of this time passing through the dense atoms that make the sun and just 8 minutes to reach us once it had left the Sun! 6. Fact: The Sun loses up to a billion kilograms a second due to solar winds

Olympic Games Facts for Kids One of the most well-known symbols of the Olympics is the five rings. Designed by de Coubertin, the interlocking rings are represented by the colors blue, yellow, black, green, and red. The rings signify the major continents that participate in the Olympics. North and South America are combined as one ring, and the continent of Antarctica is not represented. The interlocking rings are a sign of admiration that nations from around the world can unite without prejudice. The rings appear on the Olympic flag, which has a white background.

Windows to the Universe Solar System Discovery and exploration Andreas Cellarius's illustration of the Copernican system, from the Harmonia Macrocosmica (1660) For many thousands of years, humanity, with a few notable exceptions, did not recognize the existence of the Solar System. People believed Earth to be stationary at the centre of the universe and categorically different from the divine or ethereal objects that moved through the sky. Although the Greek philosopher Aristarchus of Samos had speculated on a heliocentric reordering of the cosmos,[11] Nicolaus Copernicus was the first to develop a mathematically predictive heliocentric system.[12] His 17th-century successors, Galileo Galilei, Johannes Kepler and Isaac Newton, developed an understanding of physics that led to the gradual acceptance of the idea that Earth moves around the Sun and that the planets are governed by the same physical laws that governed Earth. Structure and composition The orbits of the bodies in the Solar System to scale (clockwise from top left)

Sun Facts - Interesting Facts about the Sun (Sol) The Sun or Sol, is the star at the centre of our solar system and is responsible for the Earth’s climate and weather. The Sun is an almost perfect sphere with a difference of just 10km in diameter between the poles and the equator. The average radius of the Sun is 695,508 km (109.2 x that of the Earth) of which 20–25% is the core. Star Profile Age: 4.6 Billion YearsType: Yellow Dwarf (G2V)Diameter: 1,392,684 kmCircumference at Equator: 4,370,005.6 kmMass: 1,989,100,000,000,000,000,000 billion kg (333,060 x Earth)Surface Temperature: 5500 °C Size of the Sun Facts about the Sun One million Earths could fit inside the Sun: If a hollow Sun was filled up with spherical Earths then around 960,000 would fit inside. Eventually, the Sun will consume the Earth: When all the Hydrogen has been burned, the Sun will continue for about 130 million more years, burning Helium, during which time it will expand to the point that it will engulf Mercury and Venus and the Earth. Satellites