4 Vesta
| Discovery |
|---|
| Proper inclination | 6.39234° |
| Proper mean motion | 99.1888 deg / yr |
| Proper orbital period | 3.62944 yr (1325.654 d) |
| Precession of perihelion | 36.8729 (2343 years) arcsec / yr |
Physical characteristics of Vesta
Vesta is unique among asteroids in that it has light and dark patches on the surface, much like the moon. Ground-based observations determined that the asteroid has basaltic regions, meaning that lava once flowed across its surface.Vesta orbits the Sun between Mars and Jupiter, within the asteroid belt, with a period of 3.6 Earth years, specifically in the inner asteroid belt, interior to the Kirkwood gap at 2.50 AU.
However, even with a boost from Mars' gravity, the Dawn mission still took over three years to reach the asteroid Vesta – launching on Sept. 27th, 2007, and arriving on July 16th, 2011, (a total of 3 years, 9 months, and 19 days).
Does Asteroid Vesta Have a Moon? And 175-mile-wide Sylvia has two moons. Measuring 330 miles across, Vesta is much larger than these other examples, so a "Vesta moon" is entirely possible.
Only dwarf planet Ceres is more massive in that region of rocky debris between Mars and Jupiter. NASA's Dawn spacecraft circled Vesta from July 16, 2011 until Sept. 5, 2012, when it departed and began its journey to dwarf planet Ceres. The giant asteroid is almost spherical, and so is nearly classified a dwarf planet.
Vesta is the second most massive body in the asteroid belt, surpassed only by Ceres, which is classified as a dwarf planet. The brightest asteroid in the sky, Vesta is occasionally visible from Earth with the naked eye.
The asteroid Vesta is unique: Unlike all other minor planets, that orbit the Sun within the main belt between the orbits of Mars and Jupiter, Vesta has a differentiated inner structure: A crust of cooled lava covers a rocky mantle and a core made of iron and nickel - quite similar to the terrestrial planets Mercury,
5, 2012, when it departed and began its journey to dwarf planet Ceres. The giant asteroid is almost spherical, and so is nearly classified a dwarf planet. Unlike most known asteroids, Vesta has separated into crust, mantle and core (a characteristic known as being differentiated), much like Earth.
Physical characteristics of Vesta
Vesta is unique among asteroids in that it has light and dark patches on the surface, much like the moon. Ground-based observations determined that the asteroid has basaltic regions, meaning that lava once flowed across its surface.Liquid water once flowed across the asteroid. "Nobody expected to find evidence of water on Vesta. The surface is very cold and there is no atmosphere, so any water on the surface evaporates," study lead author Jennifer Scully, a postgraduate researcher at UCLA, said in a NASA statement.
Heinrich Wilhelm Matthias Olbers
Vesta (Latin pronunciation: [ˈw?sta]) is the virgin goddess of the hearth, home, and family in Roman religion. She was rarely depicted in human form, and was often represented by the fire of her temple in the Forum Romanum.
Vesta is the second most massive body in the asteroid belt, surpassed only by Ceres, which is classified as a dwarf planet. The brightest asteroid in the sky, Vesta is occasionally visible from Earth with the naked eye.
From Earth, the apparent magnitude of Ceres ranges from 6.7 to 9.3, peaking once at opposition every 15 to 16 months, which is its synodic period. Thus even at its brightest, it is too dim to be seen by the naked eye, except under extremely dark skies.
One Mission, Two Remarkable Destinations
They reside in the debris-strewn main asteroid belt, between Mars and Jupiter. Dawn's super-efficient ion propulsion system allowed the spacecraft to spend fourteen months in orbit at Vesta before cruising on to Ceres, where it will remain in perpetual orbit.Exploring the asteroid
Dawn entered orbit around Vesta in July 2011. NASA's Dawn mission is to study the characteristics of the early solar system by analyzing the two asteroids, which are very different. Ceres is wet, with seasonal polar caps, and may have a thin atmosphere. Vesta, on the other hand, is dry and rocky.Haumea (minor-planet designation 136108 Haumea) is a likely dwarf planet located beyond Neptune's orbit. On September 17, 2008, it was named after Haumea, the Hawaiian goddess of childbirth, under the expectation by the International Astronomical Union (IAU) that it would prove to be a dwarf planet.
Phobos is a small, irregularly shaped object with a mean radius of 11 km (7 mi) and is seven times as massive as the outer moon, Deimos. Phobos is named after the Greek god Phobos, a son of Ares (Mars) and Aphrodite (Venus) and the personification of fear (cf.
Eris (minor planet designation 136199 Eris) is the most massive and second-largest known dwarf planet in the Solar System. Eris was discovered in January 2005 by a Palomar Observatory-based team led by Mike Brown, and its discovery was verified later that year.
By this definition, Ceres is not a planet because it does not dominate its orbit, sharing it as it does with the thousands of other asteroids in the asteroid belt and constituting only about 25% of the belt's total mass.
Chiron, icy small body orbiting the Sun in the outer solar system among the giant planets. Once thought to be the most distant known asteroid, Chiron is now believed to have the composition of a comet nucleus—i.e., a mixture of water ice, other frozen gases, organic material, and silicate dust.
The solar system is indeed pretty much a flat sheet, with the major planets all orbiting in a very thin plane surrounding the Sun. Part of the reason we don't tend to send spacecraft in the 'up' direction, out of this thin plane, is simply that there's not very much there!
The orbit of Juno is significantly elliptical with a small inclination, moving between Mars and Jupiter. 3 Juno is a large asteroid in the asteroid belt. Juno was the third asteroid discovered, in 1804, by German astronomer Karl Harding.
Comets tend to have very extended and elongated orbits, many times going more than 50,000 AU from the sun (1 AU, or astronomical unit, equals the distance from the Earth to the sun). Asteroids tend to have shorter, more circular orbits and they seem to want to group together in belts.
Surface temp. Ceres /ˈs??riːz/ (minor-planet designation: 1 Ceres) is the largest object in the main asteroid belt that lies between the orbits of Mars and Jupiter. With a diameter of 940 km (580 mi), Ceres is both the largest of the asteroids and the only unambiguous dwarf planet currently inside Neptune's orbit.
Ceres is a dwarf planet, and the only who isn't located in the Kuiper Belt but rather in the inner solar system in the asteroid belt between the orbits of Mars and Jupiter.
A
dwarf planet is a
planetary-mass object that does
not dominate its region of space (as a true/classical
planet does)
and is
not a satellite.
Most likely dwarf planets.
| Name | Ceres |
|---|
| Region of the Solar System | Asteroid belt |
|---|
| Orbital radius (AU) | 2.768 |
|---|
| Orbital period (years) | 4.604 |
|---|
| Mean orbital speed (km/s) | 17.90 |
|---|
One Mission, Two Remarkable Destinations
The mission features extended stays at two very different extraterrestrial bodies: giant asteroid Vesta and dwarf planet Ceres. They reside in the debris-strewn main asteroid belt, between Mars and Jupiter. Vesta is a terrestrial world, rocky and dense like Mars and Mercury.The International Astronomical Union (IAU) downgraded the status of Pluto to that of a dwarf planet because it did not meet the three criteria the IAU uses to define a full-sized planet. Essentially Pluto meets all the criteria except one—it “has not cleared its neighboring region of other objects.”
Comets are basically dusty snowballs which orbit the Sun. They are made of ices, such as water, carbon dioxide, ammonia and methane, mixed with dust. These materials came from the time when the Solar System was formed. Comets have an icy center (nucleus) surrounded by a large cloud of gas and dust (called the coma).
Toutatis is one of the strangest objects in the solar system, with a highly irregular shape and an extraordinarily complex "tumbling" rotation. Both its shape and rotation are thought to be the outcome of a history of violent collisions.
