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Space Exploration Portal
Voyager at 90 AU ... and beyond
The Voyager journey of discovery continues. After traveling through space for more than 27 years, Voyager 1 has set a new milestone. On November 5, 2003, the spacecraft reached 90 astronomical units (AU) from the Sun. 90 AU is the equivalent of about 8.4 billion miles or 13.5 billion kilometers. It is the only spacecraft to have made measurements in the solar wind from such a great distance from the source of the dynamic solar environment.
Ulysses
Ulysses is a joint NASA and European Space Agency (ESA) mission to study the Sun at all latitudes. ESA provided the spacecraft, NASA provided the Radioisotope Thermoelectric Generator (RTG), the launch vehicle, the Inertial Upper Stage (IUS), and the Payload Assist Module (PAM-S), and is providing data reception via the Deep Space Network.
NASA's Mars Exploration Program
Since our first close-up picture of Mars in 1965, spacecraft voyages to the Red Planet have revealed a world strangely familiar, yet different enough to challenge our perceptions of what makes a planet work. Every time we feel close to understanding Mars, new discoveries send us straight back to the drawing board to revise existing theories.
You'd think Mars would be easier to understand. Like Earth, Mars has polar ice caps and clouds in its atmosphere, seasonal weather patterns, volcanoes, canyons and other recognizable features. However, conditions on Mars vary wildly from what we know on our own planet.
Over the past three decades, spacecraft have shown us that Mars is rocky, cold, and sterile beneath its hazy, pink sky. We've discovered that today's Martian wasteland hints at a formerly volatile world where volcanoes once raged, meteors plowed deep craters, and flash floods rushed over the land. And Mars continues to throw out new enticements with each landing or orbital pass made by our spacecraft.
Cassini
The Cassini mission to Saturn is the most ambitious effort in planetary space exploration ever mounted. A joint endeavor of NASA, the European Space Agency (ESA) and the Italian Space Agency (known as ASI for its acronym in Italian), Cassini is sending a sophisticated robotic spacecraft to orbit the ringed planet and study the Saturnian system in detail over a four-year period.
Messenger
MESSENGER is a scientific investigation – by spacecraft – of the planet Mercury, named after the mythological messenger of the gods. The name comes from “MErcury Surface, Space ENvironment, Geochemistry, and Ranging,” highlighting the project’s broad range of scientific goals.