Pallasite
A pallasite is a stony-iron meteorite. They contain the mineral peridot in an iron-nickel matrix.
Pallas
Related Category: Astronomy: General
(pl´s), in astronomy, 2d asteroid to be discovered. It was found in 1802 by H. Olbers. The second largest asteroid, it has a diameter of c.300 mi (480 km). Its orbit has a semimajor axis of 2.
Pallas
Table of Contents: Pallas Article Related Articles External Web sites
Article
Related Articles
External Web sites
Citations ...
Pallas
Home ... Science and Technology Astronomy and Space Exploration Astronomy: General ...
Essential reading Compare
side-by-side A Dictionary of Earth Sciences The Oxford Dictionary of ... The Columbia Encyclopedia, ...
PALLASITE - One of two main classes of stony-iron meteorite, the other being mesosiderites.
Pallas
The second asteroid to be discovered (by Olbers in 1802). Diameter about 560 km; a = 2.77 AU, e = 0.235, i = 34°.8. Orbital period 1,686 days; rotation period 9-12 hours. Albedo ~ 0.05; mass (1972 est.) 2.6 × 1023 g.
Pallasite
a stony-iron meteorite in which nodules of olivine (a silicate mineral) are surrounded by a network of iron-nickel metal.
Parallax
the apparent change in position of two objects viewed from different locations.
PALLAS
Pallas is the second-biggest asteroid and one of the four brightest asteroids. Its dimensions are: 570 x 525 x 482 km and its mass is 3.18 x 1020 kg. Pallas is about 4.145 x 108 km from the Sun and takes 4.
Pallasites
Mesosiderites
Iron meteorites (5.7%)
Meteorites have proven difficult to classify, but the three broadest groupings are stony, stony iron, and iron. The most common meteorites are chondrites, which are stony meteorites.
Pallasites: the mineral olivine enclosed in metal Mesosiderites
Stony-iron: (1.5%) iron-nickel alloy and non-metallic mineral matter.
When meteorites hit the Earth they cause a crater to form. The bigger the meteorite, the bigger the crater.
2 Pallas
'2 Pallas' is one of the largest asteroids and is located in the main asteroid belt. It was the second asteroid to be discovered, by astronomy Heinrich Wilhelm Matth?us Olbers on March 28, 1802....
, and 10 Hygiea
10 Hygiea ...
2 Pallas has an unusually high orbital inclination.
4 Vesta is the brightest of the asteroids. It is the only one that can reach the limit of naked-eye visibility, sixth magnitude.
After a gap of 38 years, 5 Astraea was discovered.
Ceres,[e] Pallas, Juno, and Vesta
The first known asteroids, from their discoveries between 1801 and 1807 until their reclassification as asteroids during the 1850s.[41]
Ceres has subsequently been classified as a dwarf planet.
It is 974 km in diameter and contains about 25% of the mass of all the asteroids combined. The next largest are 2 Pallas, 4 Vesta and 10 Hygiea which are between 400 and 525 km in diameter.
Asteroid Pallas
Asteroid Apophis
Asteroid Juno
Arizona Crater
Asteroid Mining
What are the Differences Between Asteroids and Meteors?
Asteroid Belt
Asteroid Strike
Asteroid Toutatis
What is the Difference Between Asteroids and Comets ...
Although none is visible to the naked eye, many can be seen at times with binoculars or small telescopes, including the four largest: (1) Ceres, (2) Pallas, (4) Vesta, and (10) Hygiea.
A chart of Federation space, seen in "Conspiracy", contained references to solar objects first mentioned in TAS, including the planets Canopus III, Lactra VII, Omega Cygni, Phylos and Kzin, and the stars Beta Lyrae, and Pallas 14.
The three largest asteroids in the main belt (individually named 4 Vesta, 2 Pallas and 10 Hygiea) have mean diameters of more than 400 km, while the main belt's only dwarf planet, Ceres, is about 950 km in diameter.
The densities of Ceres, Pallas, and Vesta are 2.3, 3.4, and 4.0 grams per cubic centimetre, respectively. These compare with 5.4, 5.2, and 5.5 g/cm for Mercury, Venus, and the Earth, respectively; 3.9 g/cm for Mars; and 3.3 g / cm for the Moon.
The three largest asteroids, Ceres, Pallas, and Vesta, have diameters of 940, 580, and 540 km, respectively. Only two dozen or so asteroids are more than 200 km across, and most are much smaller.
The largest representatives are Ceres, with a diameter of about 930 km (about 578 mi); Pallas, with a diameter of about 552 km (about 343 mi); and Vesta, with a diameter of about 521 km (about 324 mi).
It is interesting to note that, historically, the first four asteroids (1 Ceres, 2 Pallas, 3 Juno and 4 Vesta) were considered planets for several decades (their size was not accurately known at the time).
Heinrich Wilhelm Olbers found another, Pallas, on March 28, 1802. Karl L. Harding found a third, Juno, on Septemer 1, 1804. Olbers found the fourth, Vesta, on March 29, 1807.
The next largest asteroids are 2 Pallas, 4 Vesta and 10 Hygiea which are between 250 and 325 miles in diameter. All other known asteroids are less than 210 miles across.
PLANS TO EXPLORE VESTA
What are asteroids made of?
This element was discovered in 1803 by W. Wollaston in London. The name alludes to the asteroid Pallas discovered in 1802 by Olbers. Pallas Athene is the name of the goddess of wisdom in Greek mythology.
It is 1003 km in diameter. Pallas and Vesta have diameters of about 500 km and 30 more asteroids have diameters greater than 200 km. Most asteroids, however, are small objects only a few kilometres across.
Pallas and Vesta have diameters of about 500 kilometers and about 15 others have diameters larger than 250 kilometers. The number of asteroids shoots up with decreasing size. The combined mass of all of the asteroids is less than the Moon's mass.
Discovered several comets, searched for missing planet between Mars and Jupiter forecasted by Bode’s Law and discovered Pallas and Vesta suggesting these were fragments of the missing planet, formulated Olber’s Paradox.
Ceres, the largest Main-Belt asteroid, has been acknowledged by many astronomers as a dwarf planet. In addition, the next three largest asteroids in the Main Belt (Vesta, Pallas, and Hygeia) may also be "round enough" to be eventually classified as ...
and physician who published Olbers' paradox (Why is the sky dark at night? or Why doesn't starlight make the night sky bright?) (1823), determined that Uranus is a planet, not a comet (1781), discovered Olbers's comet (1815), the asteroids #2 Pallas ...
1802 - Heinrich Wilhelm Olbers discovers the asteroid Pallas
1821 - Alexis Bouvard detects irregularities in the orbit of Uranus ...
 See also: Asteroid, Solar, Planet, Earth, Solar System
|
