Magellan (spacecraft)

The mass of the apparatus with fuel is 3.5 tons, length - 4.6 meters, diameter of the radar antenna - 3.7 meters. The Magellan was equipped with two square solar panels with a side length of 2.5 m. The apparatus did not have a camera. The radar (wavelength 12.6 cm) allowed for cartography with a resolution of 100-300 meters and height measurements with an accuracy of 30-50 meters.

The main contractor for the creation of Magellan was Martin Marietta (now Lockheed Martin ).

In August 1990, Magellan entered an elongated polar orbit around Venus with altitudes from 295 km to 8500 km and a circulation period of 195 minutes.

At each moment of approaching the planet, the device using a radar mapped a narrow strip with a width of 17 to 28 km. By September 1992, the device was shooting 98% of the surface of the planet. Since Magellan repeatedly shot many areas from different angles, this made it possible to draw up a three-dimensional model of the surface, and also to study possible changes in the landscape. A stereo image was obtained for 22% of the surface of Venus.

Before Magellan, less detailed mapping of Venus was carried out by the Pioneer-Venus-1 , Venus-15 and Venus-16 devices with a resolution of 1-2 km.

Creating a detailed map helped to better understand the geology of Venus. There are relatively few craters on the planet, but volcanic formations (lava plains, etc.) are often found. The surface of Venus is young by geological standards - less than 800 million years. The device has found many interesting features (for example, extended "channels" of super-viscous lava). Oddly enough, on Venus (unlike Mars ) no significant signs of wind erosion were found, and the atmospheric transport of dust and sand is limited.

From September 1992 to May 1993, Magellan explored the gravitational field of Venus. During this period, he did not radar the surface, but broadcast a constant radio signal to Earth. By changing the signal frequency, it was possible to determine the slightest changes in the speed of the device ( Doppler effect ), which, in turn, made it possible to detect features of the planet’s gravitational field.

From May to August 1993, Magellan tried out atmospheric braking technology. The lower point of the orbit was slightly reduced so that the apparatus touched the upper layers of the atmosphere and changed the parameters of the orbit without fuel consumption. In August, the Magellan’s orbit was 180–540 km in altitude with a circulation period of 94 minutes. This allowed for more accurate gravity measurements. In general, a “gravity map” was compiled for 95% of the planet’s surface.

In September 1994, an experiment was conducted to study the upper atmosphere of Venus. The solar panels of the device were deployed like the blades of a windmill, and the orbit of the Magellan was reduced. This made it possible to obtain information on the behavior of molecules in the uppermost layers of the atmosphere. On October 11, the orbit was reduced for the last time, and on October 12, 1994, contact with the device, approaching Venus in a spiral, was lost.

• Pioneer Venus-1
• Venus Program
• Maat Mons - Venusian Volcano

• Project page on NASA website
• Project Description
• Images taken by Magellan