MARINER 2
       The first spacecraft to study Venus or any other planet upclose was the U.S. 
Mariner 2. Launched on August 27, 1962. It flew by the planet on Dec. 14, 1962 after 
traveling for 3 1/2 months. It was designed to take measurements of the magnetic fields in 
the inner solar system, solar wind and cosmic dust. It was also equipped with a microwave 
radiometer to find if the massive amounts of microwaves emanating from the planet was 
actually from the surface of Venus. It was finally concluded through the Mariner 2 that 
Venus' surface was as hot as 900 degrees Fahrenheit (735 degrees Kelvin). The Venera 1 was 
launched before the Mariner 2, but was unsuccesful and failed.

SOVIET CRAFTS AND THE MARINER 5 AND PIONEER VENUS
       Later, the Soviet spacecraft, Venera 2 flew by Venus on Feb 27, 1966. The Venera 3 
launched 4 days after the Venera 2 reached Venus on March 1, 1966, but crashed into it. The 
Venera 3 was actually designed to be the first spacecraft to land on a planet but it never 
got to do that. Then came a series of spacecraft from both the Soviet Union and the U.S.A.. 
The Soviet Venera 4 capsule was parachuted down into the atmosphere of Venus on 
Oct. 18, 1967. Venera 4 was the first spacecraft to enter another planet's atmosphere. 
It was a success until the atmospheric pressure was too great, at 18 atmospheres (8 time 
the atmospheric pressure of Earth on the surface). The temperature was also getting too hot 
at 500 degrees Fahreinheit. Venera 4 confirmed that the atmosphere was made mostly of carbon
dioxide, the temperatures were very hot and atmospheric pressure was great. The next day 
the U.S. Mariner 5 (launched 2 days after the Venera 4) passed within 2,480 miles of Venus 
and was more successful at collecting information about Venus. It was loaded with the most 
up to date equipment of that time. It found out that the surface temperature was about 980 
degrees Fahreinheit and the atmospheric pressure was 100 atmoshperes.
       A few years later, the Venera 7 landed on Venus on Dec. 15, 1970, which made it 
through but fell over on impact, so no data could be sent. This came after the Soviets had 
launched the Venera 5 and 6 on Jan 5 and 10 of 1969. The Venera 8 was more successful, which
landed on July 22, 1972 and was able to transport data about the ground conditions, like 
illumination level and rock properties on the surface. The Venera 9 and Venera 10, also 
followed and landed on Venus. The U.S., in December 1978 sent the crafts Pioneer Venus 1 to 
orbit the planet and Pioneer Venus Bus and the 4 probes it carried entered Venus' 
atmosphere. More Soviet Venera crafts, the 11 and 12 also landed on Venus in 
December 1978, and the 13 and 14 in March.

MAGELLAN
       In 1990, many years later the U.S. spacecraft, the Magellan, began orbiting Venus on 
Aug. 10. Magellan was equipped with modern instruments that provided radar images detailed 
enough to make maps of many features. The Magellan was launched May 1989 on the shuttle 
Atlantis. The Magellan sent back to us more than 1 trillion bytes of data during its 5 year 
mission. Also Magellan increased the number of named Venusian features from 300 to 1,000. 
It's mission ended in October 1994. Even though it's dead now, Magellan mapped 99 percent of
Venus. It used radar mapping in its first phase and collected gravity data in its second 
phase. The radar mapping was done by bouncing thousands of pulses of radio energy each 
second, and then recieving the radar signals that bounced off the surface. It also collected
altimetry data, data about how tall each feature was. The Magellan also collected radiometry
data so that scientists could have an idea what the chemistry of the surface was. A much 
clearer picture of what Venus was like became known to us after Magellan. Scientists have 
analyzed the data and discovered that Venus may have a core that allows plate tectonics to 
come into play. Still, Venus is very far from being twins with Earth.