Search results
Results from the WOW.Com Content Network
[1] [2] The low eccentricity and comparatively small size of its orbit give Venus the least range in distance between perihelion and aphelion of the planets: 1.46 million km. The planet orbits the Sun once every 225 days [3] and travels 4.54 au (679,000,000 km; 422,000,000 mi) in doing so, [4] giving an average orbital speed of 35 km/s (78,000 ...
Vesta (radius 262.7 ± 0.1 km), the second-largest asteroid, appears to have a differentiated interior and therefore likely was once a dwarf planet, but it is no longer very round today. [74] Pallas (radius 255.5 ± 2 km ), the third-largest asteroid, appears never to have completed differentiation and likewise has an irregular shape.
Thus, the 243-year cycle is relatively stable, but the number of transits and their timing within the cycle vary over time. [2] Since the 243:395 Earth:Venus commensurability is only approximate, there are different sequences of transits occurring 243 years apart, each extending for several thousand years, which are eventually replaced by other ...
According to data from the Pioneer Venus Orbiter altimeters, nearly 51% of the surface is located within 500 meters (1,600 feet) of the median radius of 6,052 km (3,761 mi); only 2% of the surface is located at elevations greater than 2 kilometres (1.2 mi) from the median radius.
Venus's equator rotates at 6.52 km/h (4.05 mph), whereas Earth's rotates at 1,674.4 km/h (1,040.4 mph). [note 2] [153] Venus's rotation period measured with Magellan spacecraft data over a 500-day period is smaller than the rotation period measured during the 16-year period between the Magellan spacecraft and Venus Express visits, with a ...
On this assumption, a two-year return is not possible for some years, and for some years a delta-v kick of 0.6 to 2.7 km/s at Mars may be needed to get back to Earth. [ 10 ] NASA published the Design Reference Architecture 5.0 for Mars in 2009, advocating a 174-day transfer to Mars, which is close to Zubrin's proposed trajectory. [ 11 ]
For example, if a TNO is incorrectly assumed to have a mass of 3.59 × 10 20 kg based on a radius of 350 km with a density of 2 g/cm 3 but is later discovered to have a radius of only 175 km with a density of 0.5 g/cm 3, its true mass would be only 1.12 × 10 19 kg.
[11] [12] It seems to have been co-orbital with Venus for only the last 7,000 years, and is destined to be ejected from this orbital arrangement about 500 years from now. [6] During this time, its distance to Venus has been and will remain larger than about 0.2 astronomical units (30,000,000 km; 19,000,000 mi).