Our journey into space has deepened humankind’s understanding of the universe and ourselves, it has advanced technology, enhanced our lives, and expanded the frontiers of science; but most of all it has instilled a sense of curiosity in each of us; a curiosity that has lead generations to pursue careers in science, question the unknown, and seek answers that were thought impossible to obtain. The solar system is our home and it is an exciting place to be; full of planets, moons, asteroids, comets, and countless wonders. Space is truly the next frontier.
Solar Scroller is a travel-able to-scale and accurately animated model of our solar system. Built with HTML5 and PHP, some of the most complex CSS3 animations, and powered by a completely custom jquery library - Solar Scoller not only shows the wonders of our solar system but the possibilities of CSS.
Climb on board Solar Scroller and embark on a mission to learn about the planets, satellites, dangers, and challenges of traveling our galactic neighborhood. On your mission you will witness the complex relationships of planets and satellites within our solar system.
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields. It has a diameter of about 1,392,684 km (865,374 mi), around 109 times that of Earth, and its mass (1.989×1030 kilograms, approximately 330,000 times the mass of Earth) accounts for about 99.86% of the total mass of the Solar System. Chemically, about three quarters of the Sun's mass consists of hydrogen, while the rest is mostly helium. The remaining 1.69% (equal to 5,600 times the mass of Earth) consists of heavier elements, including oxygen, carbon, neon and iron, among others..
The Sun formed about 4.567 billion years ago from the gravitational collapse of a region within a large molecular cloud. Most of the matter gathered in the center, while the rest flattened into an orbiting disk that would become the Solar System. The central mass became increasingly hot and dense, eventually initiating thermonuclear fusion in its core. It is thought that almost all stars form by this process. The Sun is a G-type main-sequence star (G2V) based on spectral class and it is informally designated as a yellow dwarf because its visible radiation is most intense in the yellow-green portion of the spectrum, and although it is actually white in color, from the surface of the Earth it may appear yellow because of atmospheric scattering of blue light. In the spectral class label, G2 indicates its surface temperature, of approximately 5778 K (5505 °C, 9941 °F), and V indicates that the Sun, like most stars, is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses about 620 million metric tons of hydrogen each second.
Once regarded by astronomers as a small and relatively insignificant star, the Sun is now thought to be brighter than about 85% of the stars in the Milky Way, most of which are red dwarfs. The absolute magnitude of the Sun is +4.83; however, as the star closest to Earth, the Sun is by far the brightest object in the sky with an apparent magnitude of −26.74. This is about 13 billion times brighter than the next brightest star, Sirius, with an apparent magnitude of −1.46. The Sun's hot corona continuously expands in space creating the solar wind, a stream of charged particles that extends to the heliopause at roughly 100 astronomical units. The bubble in the interstellar medium formed by the solar wind, the heliosphere, is the largest continuous structure in the Solar System
The Sun is currently traveling through the Local Interstellar Cloud (near to the G-cloud) in the Local Bubble zone, within the inner rim of the Orion Arm of the Milky Way. Of the 50 nearest stellar systems within 17 light-years from Earth (the closest being a red dwarf named Proxima Centauri at approximately 4.2 light-years away), the Sun ranks fourth in mass. The Sun orbits the center of the Milky Way at a distance of approximately 24000–26000 light-years from the galactic center, completing one clockwise orbit, as viewed from the galactic north pole, in about 225–250 million years. Since the Milky Way is moving with respect to the cosmic microwave background radiation (CMB) in the direction of the constellation Hydra with a speed of 550 km/s, the Sun's resultant velocity with respect to the CMB is about 370 km/s in the direction of Crater or Leo.
The mean distance of the Sun from the Earth is approximately 1 astronomical unit (about 150,000,000 km; 93,000,000 mi), though the distance varies as the Earth moves from perihelion in January to aphelion in July.[30] At this average distance, light travels from the Sun to Earth in about 8 minutes and 19 seconds. The energy of this sunlight supports almost all life[b] on Earth by photosynthesis,[31] and drives Earth's climate and weather. The enormous effect of the Sun on the Earth has been recognized since prehistoric times, and the Sun has been regarded by some cultures as a deity. An accurate scientific understanding of the Sun developed slowly, and as recently as the 19th century prominent scientists had little knowledge of the Sun's physical composition and source of energy. This understanding is still developing; there are a number of present-day anomalies in the Sun's behavior that remain unexplained.
Mercury is the innermost planet in our solar system. Because of its small size – a diameter of 3030 miles – it is not the easiest of planets to observe. German scientist Johannes Hevelius (1611 - 1687) was among the first to observe a Mercurial transit and discovered the Mercurial phases. Most of our information has been collected by the Mariner 10 space probe that made three successful passes of the planet (March 29 1974, September 21 1974, and March 16 1975) before losing contact with Earth. Averaging an orbital velocity of 47.87 km per second, Mercury is the fastest-moving planet in our solar system.
Because of its low escape velocity, Mercury hasn't much of an atmosphere. Based on information from Mariner 10, its surface pressure is ten billionths of a millibar. This barely extant atmosphere includes trace amounts of hydrogen and helium from the solar wind. In 1991, very powerful radio telescopes noticed large sheets of ice contained on the poles, areas unseen by Mariner 10. Due to its 3600 km iron core, Mercury has the greatest density in our Solar System apart from Earth. Composed of 70% iron and 30% rock, Mercury has a molten core, a 600-km thick mantle, and a crust of silicates. Its largest known surface feature is the Caloris Basin with a 1350 km diameter. Mariner 10 also detected a magnetosphere with a 1% surface value of Earth's. Mercury's magnetic field is inclined at 11% to its rotational axis and has the same polarity as Earth's – just enough to protect it from the full force of the solar wind. Mercury's 0.06 albedo is due to a dark-colored, rough, porous rock that does not reflect much light; its climate indicates a slim chance life could exist there.
Due to the small difference between Mercury's orbital and rotational periods, the interval between night and day on the planet itself is 88 Earth days. This leads to a few peculiarities. As a result of orbital eccentricity, the temperature as measured at perihelion is two and a half times the heat received at aphelion. To an observer situated on the planet's hot pole at aphelion during a sunrise, the Sun would approach the zenith (getting larger as it does so), but since the orbital angular velocity is greater than the constant-spin angular velocity for a time, the Sun appears to stop, retreat backward for 8 Earth days, stop again, and then resume its original course.
Of all the inner rocky planets, Mercury is the least explored with only 45% of its surface photographed. Though it is two thirds iron, the actual reason for this is a mystery to solve. Some scientists believe it was originally a rocky planet that somehow lost its exterior. Mercury and Earth are the only rocky planets with global magnetic fields. Equatorial temperatures on Mercury can reach 450°C and though signatures of ice craters have been detected at high latitudes with temperatures reaching below -184°C, some scientists believe the 'ice' might just be super-frozen silicon. Coated with heat-resistant ceramic fabric.
Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. It has no natural satellite. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows. Because Venus is an inferior planet from Earth, it never appears to venture far from the Sun: its elongation reaches a maximum of 47.8°. Venus reaches its maximum brightness shortly before sunrise or shortly after sunset, for which reason it has been referred to by ancient cultures as the Morning Star or Evening Star.
Venus is a terrestrial planet and is sometimes called Earth's "sister planet" because of their similar size, gravity, and bulk composition (Venus is both the closest planet to Earth and the planet closest in size to Earth). However, it has also been shown to be very different from Earth in other respects. It has the densest atmosphere of the four terrestrial planets, consisting of more than 96% carbon dioxide. The atmospheric pressure at the planet's surface is 92 times that of Earth's. With a mean surface temperature of 735 K (462 °C; 863 °F), Venus is by far the hottest planet in the Solar System. It has no carbon cycle to lock carbon back into rocks and surface features, nor does it seem to have any organic life to absorb it in biomass. Venus is shrouded by an opaque layer of highly reflective clouds of sulfuric acid, preventing its surface from being seen from space in visible light. Venus may have possessed oceans in the past, but these would have vaporized as the temperature rose due to a runaway greenhouse effect. The water has most probably photo-dissociated, and, because of the lack of a planetary magnetic field, the free hydrogen has been swept into interplanetary space by the solar wind. Venus's surface is a dry desertscape interspersed with slab-like rocks and periodically refreshed by volcanism
Earth, also known as "the Earth" and "the World" and sometimes referred to as the "Blue Planet", the "Blue Marble", Terra or "Gaia", is the third-closest planet to the Sun, the densest planet in the Solar System, the largest of the Solar System's four terrestrial planets and the only celestial body known to accommodate life. It is home to millions of species, including a global population of humans, that are supported and nourished by its biosphere and minerals. The human population is grouped into around two-hundred independent sovereign states that interact, among other means, through diplomacy, conflict, travel, trade and media.
According to evidence from sources such as radiometric dating, Earth was formed around four and a half billion years ago. Within its first billion years, life appeared in its oceans and began to affect its atmosphere and surface, promoting the proliferation of aerobic as well as anaerobic organisms and causing the formation of the atmosphere's ozone layer. This layer and Earth's magnetic field block the most life-threatening parts of the Sun's radiation, so life was able to flourish on land as well as in water. Since then, Earth's position in the Solar System, its physical properties and its geological history have allowed life to persist.
Earth's lithosphere is divided into several rigid segments, or tectonic plates, that migrate across the surface over periods of many millions of years. Over 70% percent of Earth's surface is covered with water, with the remainder consisting of continents and islands which together have many lakes and other sources of water that contribute to the hydrosphere. Earth's poles are mostly covered with ice that is the solid ice of the Antarctic ice sheet and the sea ice that is the polar ice packs. The planet's interior remains active, with a solid iron inner core, a liquid outer core that generates the magnetic field, and a thick layer of relatively solid mantle.
Earth gravitationally interacts with other objects in space, especially the Sun and the Moon. During one orbit around the Sun, the Earth rotates about its own axis 366.26 times, creating 365.26 solar days, or one sidereal year. The Earth's axis of rotation is tilted 23.4° away from the perpendicular of its orbital plane, producing seasonal variations on the planet's surface with a period of one tropical year (365.24 solar days). The Moon is Earth's only natural satellite. It began orbiting the Earth about 4.53 billion years ago (bya). The Moon's gravitational interaction with Earth stimulates ocean tides, stabilizes the axial tilt, and gradually slows the planet's rotation.
The Moon or Luna is the Earth's only natural satellite. It is, among the satellites of major planets, the largest relative to the size of the object it orbits, Earth, and, after Jupiter's satellite Io, it is the second most dense satellite among those whose densities are known.
The Moon is in synchronous rotation with Earth, always showing the same face with its near side marked by dark volcanic maria that fill between the bright ancient crustal highlands and the prominent impact craters. It is the most luminous object in the sky after the Sun. Although it appears a very bright white, its surface is actually dark, with a reflectance just slightly higher than that of worn asphalt. Its prominence in the sky and its regular cycle of phases have, since ancient times, made the Moon an important cultural influence on language, calendars, art, and mythology. The Moon's gravitational influence produces the ocean tides and the slight lengthening of the day. The Moon's current orbital distance is about thirty times the diameter of Earth, causing it to have an apparent size in the sky almost the same as that of the Sun. This allows the Moon to cover the Sun nearly precisely in total solar eclipse. This matching of apparent visual size is a coincidence. The Moon's linear distance from Earth is currently increasing at a rate of 3.82±0.07 cm per year, but this rate is not constant.
The Moon is thought to have formed nearly 4.5 billion years ago, not long after Earth. Although there have been several hypotheses for its origin in the past, the current most widely accepted explanation is that the Moon formed from the debris left over after a giant impact between Earth and a Mars-sized body.
Mars is the fourth planet from the Sun. It is also the second nearest planet to the Earth and will probably be the first planet visited by humans. It has an orbital period equal to 687 Earth days and a rotational period equal to 24hrs 37mins and 22.6 seconds. Therefore there are 668 Martian days in a Martian Year. Mars has a very eccentric orbit that can vary from 249 million km to 207 million km. As a result, it also experiences seasons. "
When it is nearest to Earth – 59 million km away – Mars can be seen in great detail even with small telescopes. The polar ice caps are visible; the southern ice cap can extend down to 50° latitude or become quite small depending on the season. There are many bright areas on the red planet, e.g. 'Hellas', that are in fact deep basins on the planet's surface. There are also dark areas on the planet's surface, e.g. 'Sirtis Major' (in the shape of a large 'V'), that were once thought to be seas, but when the atmospheric pressure was discovered to be too low for liquid water, the dark areas were then thought to be old sea beds filled with vegetation. However all this was disproved after the first fly-by mission by Mariner 4 in 1965. And two NASA rovers, Spirit and Opportunity, have since beamed back images of the Martian surface, which they explored.
The highest known surface point on Mars is a huge volcano known as 'Olympus Mons'. It stretches 24km high above the lava plains around it and it has a base measuring 600km. Mars has an average surface temperature of about -23°C. Its atmospheric content includes 95% carbon dioxide, 3% nitrogen and 1.6% argon. Mars is not as dense or as large as Earth and has an escape velocity of 5km/sec, only enough to sustain a thin, transparent atmosphere. However, some clouds can be seen and from time to time the occasional dust storm can completely cover the Martian surface. The storms occur when wind speed increases to 50-100 meters per second as dust from the surface is lifted up and bounces along the ground, colliding with other dust particles and forcing a cataclysmic reaction that could encompass the entire Martian globe. The technical name for this is 'saltation'.
The bright rust color Mars is known for is due to to iron-rich minerals in its regolith — the loose dust and rock covering its surface. The soil of Earth is a kind of regolith, albeit one loaded with organic content.
Mars has two moons, Phobos and Deimos, both discovered in 1877 by Asaph Hall. These two moons are shaped irregularly and are probably asteroids that were caught by Mars' gravitational pull a long time ago. Neither is large enough to become spherical, and both have synchronous rotations enabling them to always keep the same face toward their parent planet.
Phobos orbits at a distance of less than 6000 km from the surface of Mars and, with a maximum diameter of 27 km, is larger than Deimos. Phobos has been falling very slowly toward the planet at a rate of 10 km every century, because of which it will collide with Mars in forty million years. Phobos' surface is covered with craters (the largest is the 10 km-long "Stickney," which was named after Asaph Hall's wife). Phobos has an orbital period of 7 hours and 39 minutes. Deimos is even smaller than Phobos. Its longest diameter is 15 km and it orbits 23400 km from the planet's centre and, unlike Phobos, has a stable orbit.
Ceres is the largest object in the asteroid belt, which lies between the orbits of Mars and Jupiter. It is a ball of rock and ice 950 km (590 mi) in diameter, containing a third of the mass of the asteroid belt. It is the largest asteroid, and the only dwarf planet in the inner Solar System. It was the first asteroid to be discovered, on 1 January 1801 by Giuseppe Piazzi in Palermo, though at first it was considered to be a planet.
Scientists describe Ceres as an "embryonic planet." Gravitational perturbations from Jupiter billions of years ago prevented it from becoming a full-fledged planet. Ceres ended up among the leftover debris of planetary formation in the main asteroid belt.
Ceres has more in common with Earth and Mars than its rocky neighbors. There are signs that Ceres contains large amounts of pure water ice beneath its surface. This was somewhat unexpected, as large bodies in the asteroid belt do not typically emit vapor, a hallmark of comets. Scientists using the Herschel Space Observatory found evidence for water vapor on Ceres: plumes of water vapor are thought to shoot up periodically from Ceres when portions of its icy surface are warmed by the sun during the course of its orbit. This proves that Ceres has a icy surface and an atmosphere as well. Astronomers estimate that if Ceres were composed of 25 percent water, it may have more water than all the fresh water on Earth. Ceres' water, unlike Earth's, would be in the form of water ice and located in the mantle, which wraps around the asteroid's solid core.
Jupiter is the fifth planet from the sun and the largest in the solar system. Named after the ruler of the gods in Roman mythology, Jupiter has 1400 times the volume of Earth but only 318 times more mass. Thus, the mean density of Jupiter is about one-fourth that of Earth, indicating that the giant planet must consist of gas rather than the metals and rocks of which the Earth and other inner planets are composed.
Once every 11.9 Earth years, Jupiter makes a complete orbit around the sun at a mean distance 5.2 times greater than one astronomical unit even though it rotates once on its axis every 9.9 hours, causing a bulge at its equator visible with a telescope (Jupiter's rotation is not uniform). Colorful latitudinal bands, atmospheric clouds, and storms illustrate Jupiter's dynamic weather systems; the cloud patterns change within hours or days.
The Great Red Spot is a complex storm moving in a counter-clockwise direction. At its outer edge, material appears to rotate in four to six days; near the center, motions are small and nearly random in direction. An array of other smaller storms and eddies can be found throughout the banded clouds. Aurora emissions, similar to Earth's Northern Lights, have been observed at Jupiter's poles and appear to be related to material from Io that spirals along magnetic field lines eventually falling into Jupiter's atmosphere. Cloud-top lightning bolts, similar to superbolts in Earth's high atmosphere, have also been observed.
The Great Red Spot is a complex storm moving in a counter-clockwise direction. At its outer edge, material appears to rotate in four to six days; near the center, motions are small and nearly random in direction. An array of other smaller storms and eddies can be found throughout the banded clouds. Aurora emissions, similar to Earth's Northern Lights, have been observed at Jupiter's poles and appear to be related to material from Io that spirals along magnetic field lines eventually falling into Jupiter's atmosphere. Cloud-top lightning bolts, similar to superbolts in Earth's high atmosphere, have also been observed.
Saturn, the large gas giant beyond Jupiter and sixth planet from the Sun, is one of the five (Mercury, Venus, Mars and Jupiter) planets visible from Earth using only the naked-eye. Galileo, with his rather primitive refracting telescope, was the first to observe Saturn's complex ring system. Since then Saturn has been seen as a symbol of the majesty, mystery, and order of the physical universe. Although many other planets do indeed have ring systems (Jupiter, Uranus and Neptune) they are not nearly as extensive nor brilliant. While the origin of these great rings is at present unknown, scientists hope to learn more through studying the planet's history with the aid of space probes such as Cassini.
Uranus is the seventh planet from the Sun and the third of the four gas giants, revolving outside the orbit of Saturn and inside the orbit of Neptune. Uranus was accidentally discovered in 1781 by the British astronomer Sir William Herschel and was originally named the Georgium Sidus (Star of George), in honour of his royal patron King George III of Great Britain. The planet was later, for a time, called Herschel in honour of its discoverer. The name Uranus, which was first proposed by the German astronomer Johann Elert Bode, was in use by the late 19th century.
Neptune is the fourth largest of the planets in the solar system and eighth major planet in order of increasing distance from the Sun. It is similar in size and structure to its neighbor Uranus. Neptune is, on average, about 4.5 billion km (2.8 billion miles) from the sun. It is about 49,400 km (30,700 miles) in diameter, or about 3.8 times as wide as the earth. Even though Neptune's volume is 72 times that of Earth's, its mass is only 17 times Earth's mass.
Pluto is a cold dark dwarf planet in which the Sun appears as only a bright star in the sky. Pluto was discovered as the result of a telescopic search inaugurated in 1905 by the American astronomer Percival Lowell, who postulated the existence of a distant planet beyond Neptune as the cause of slight perturbations in the motions of Uranus. Continued by members of the Lowell Observatory staff, the search ended successfully in 1930, when the American astronomer Clyde William Tombaugh found Pluto near the position Lowell had predicted. It was known as the ninth and outermost planet in the Solar System for over 70 years until re-designated as a dwarf planet by the International Astronomical Union following the discovery of a new solar system body: Eris.