UPSC: NASA’S VOYAGER 2 PROBE NEARING INTERSTELLAR SPACE
(This diagram shows the position of the Voyager 1 and Voyager 2 probes, relative to the heliosphere, a protective bubble created by the Sun that extends well past the orbit of Pluto. Voyager 1 crossed the heliopause, or the edge of the heliosphere, in 2012. Voyager 2 is still in the heliosheath, or the outermost part of the heliosphere.)
- NASA launched the Voyager 1 spacecraft on September 5 1977, and the Voyager 2 on August 20 1977
- The Voyagers have set several records, including Voyager 1 being the only craft to fly by all four outer planets
- Voyager 2 is a little less than 11 billion miles (about 17.7 billion kilometers) from Earth
- Once it exits heliosphere, will become second human-made object after Voyager 1, to enter interstellar space
Since late August, the Cosmic Ray Subsystem instrument on Voyager 2 has measured about a 5 percent increase in the rate of cosmic rays hitting the spacecraft compared to early August, NASA said.
The probe’s Low-Energy Charged Particle instrument has detected a similar increase in higher-energy cosmic rays.Cosmic rays are fast-moving particles that originate outside the solar system.
Some of these cosmic rays are blocked by the heliosphere, so mission planners expect that Voyager 2 will measure an increase in the rate of cosmic rays as it approaches and crosses the boundary of the heliosphere.
NASA’S HISTORIC INSTERSTELLAR VOYAGER MISSION
- The Voyager spacecraft were built by NASA’s Jet Propulsion Laboratory in Pasadena, California, which continues to operate both.
- Nasa launched the Voyager 1 spacecraft on September 5 1977, and the Voyager 2 on August 20 1977.
- Each spacecraft carries a golden record on board – a record that includes sounds, pictures and messages of Earth.
- Continuing on their more-than-37-year journey since their 1977 launches, they each are much farther away from Earth and the sun than Pluto.
- In August 2012, Voyager 1 made the historic entry into interstellar space, the region between stars, filled with material ejected by the death of nearby stars millions of years ago.
- Scientists hope to learn more about this region when Voyager 2, in the ‘heliosheath’ — the outermost layer of the heliosphere where the solar wind is slowed by the pressure of interstellar medium — also reaches interstellar space.
- Both spacecraft are still sending scientific information about their surroundings through the Deep Space Network, or DSN.
- The primary mission was the exploration of Jupiter and Saturn.
- After making a string of discoveries there — such as active volcanoes on Jupiter’s moon Io and intricacies of Saturn’s rings — the mission was extended.
- Voyager 2 went on to explore Uranus and Neptune, and is still the only spacecraft to have visited those outer planets.
- The adventurers’ current mission, the Voyager Interstellar Mission (VIM), will explore the outermost edge of the Sun’s domain. And beyond.