What is Magellan Mission?

About Magellan Mission:

• It was a deep space mission launched by NASA on May 4, 1989, to explore the planet Venus.
• It was launched from Cape Canaveral aboard the space shuttle Atlantis. It was the first interplanetary mission launched from the Space Shuttle and the first spacecraft to use the Inertial Upper Stage booster.
• It was named after the Portuguese explorer Ferdinand Magellan, who was the first to circumnavigate the earth.
• The primary goal of the Magellan mission was to map the surface of Venus using radar imaging, as the thick atmosphere of the planet made visual observation difficult.
• The Magellan spacecraft, which arrived at Venus in 1990, made the first global map of the surface of Venus as well as global maps of the planet's gravity field.
• The mission produced surprising findings about Venus, including a relatively young planetary surface possibly formed by lava flows from planet-wide volcanic eruptions.
• In October 1994, the Magellan spacecraft intentionally plunged to the surface of Venus to gather data on the planet's atmosphere before it ceased operations.

It marked the first time an operating planetary spacecraft had been intentionally crashed.

Q1: What is radar imaging?

A radar imaging system can be thought of as an echo measurement system. The radar antenna emits thousands of pulses of microwave radiation and measures the characteristics of associated echoes. The radar determines the range between the antenna and the reflecting object, the amplitude of the return wave, and its phase. That is, the radar can determine if the wave returns at its peak or trough, or somewhere in between. These measurements of range, amplitude, and phase are processed together to form images and many other useful products.

Source: NASA’s Magellan radar suggests volcanoes on Venus are still active