The Interior of Venus

The brief lifetime of instruments on Venus's inhospitable surface means that few relevant measurements have been made that shed light on Venus's interior. Because Venus formed near the Earth in the solar nebula it is expected to have a similar bulk composition, but all other calculations of its internal structure and conditions need to be made from orbital data.The rocks on the surface ofVenus are thought to be exclusively volcanic. The compositions of several surface rocks were measured by the...

Fundamental Facts about the

Average density acceleration of gravity where atmospheric pressure is one bar magnetic field strength near sunspots magnetic field strength in polar regions rotational period 432,000 miles (695,000 km), or 10 times Jupiter's radius and 104 times Earth's radius 0.00005 (almost a perfect sphere) 3.38 X 1017 cubic miles (1.41 X 1018 km3), or 1,306,000 times the volume of the Earth 4.385 X 1030 pounds (1.989 X 1030 kg), or 333,000 times the mass of Earth 87.9 pounds per cubic feet (1,410 kg m3) 900...

Venus Fast Facts about a Planet in Orbit

Venus, Earth's closest neighbor, sometimes shines brightly enough to cast shadows on Earth. The planet shines from the west after sunset and from the east after sunrise. The clear shining of the planet both in the morning and evening caused the ancient Greeks to believe for some time that the brilliance was caused by two separate heavenly objects, which they called Vesper (evening) and Phosphor (morning). The planet's brightness made it an obvious target for observations starting in the 17th...

Accretion and Heatin g Why Are Some Solar System Objects Round andOthers Irregular

T here are three main characteristics of a body that determine whether it will become round. The first is its viscosity, that is, its ability to flow. Fluid bodies can be round because of surface tension, no matter their size self-gravitation does not play a role. The force bonding together the molecules on the outside of a fluid drop pull the surface into the smallest possible area, which is a sphere. This is also the case with gaseous planets, like Uranus. Solid material, like rock, can flow...

Light Wavelength and Radiation

Electromagnetic radiation is energy given off by matter, traveling in the form of waves or particles. Electromagnetic energy exists in a wide range of energy values, of which visible light is one small part of the total spectrum. The source of radiation may be the hot and therefore highly energized atoms of the Sun, pouring out radiation across a wide range of energy values, including of course visible light, and they may also be unstable (radioactive) elements giving off radiation as they...

Heat and Light

Energy from the Sun allows plants to grow and hence is the source of the energy for all life on Earth. On the Earth and on other planets with atmospheres, solar heat creates clouds and wind and is therefore the major source of energy for all weather, except on planets with very high levels of heat flow from their interiors Jupiter, Saturn, and Neptune, though not Uranus . For the last several hundred years, people have known that the energetic output of the Sun varies. This variance can be seen...