Thursday, September 12, 2013

When NASA’s Voyager 1 spacecraft became the first manmade object to enter interstellar space, it claimed an iconic place in the history of space exploration—and underscored the University of Iowa's role and legacy among the stars.

Voyager 1 stands at the pinnacle. However, it didn’t get there alone. There were hundreds of people working on all aspects of the spacecraft, its operations, and science—many of whom are from the UI. The university's engineers produced one of Voyager’s scientific instruments, and UI scientists and technical staff have analyzed and interpreted its measurements for the 36 years since Voyager's launch.

Voyager 1 spacecraft reaches interstellar space

University of Iowa space physicist Don Gurnett says there is solid evidence that NASA’s Voyager 1 spacecraft has become the first manmade object to reach interstellar space, more than 11 billion miles distant and 36 years after it was launched. Gurnett is principal investigator for the Voyager 1 Plasma Wave Instrument. Read more...

Take the UI-designed-and-built Plasma Wave instrument: The probe continuously sampled the level of particles flowing outward from the sun and let scientists know when that level had dropped to a point where the spacecraft was nearing a faraway solar boundary called the heliopause. Just as important, the instrument told scientists when the level of particles increased to numbers that indicated the Voyager was traveling in interstellar space.

But even before the Plasma Wave instrument told us that Voyager 1 had embarked on a journey among the stars, it enabled Don Gurnett and his colleagues to make several key observations.

Gurnett, physics and astronomy professor at the UI and principal investigator of the Plasma Wave instrument, used data from the UI-built probe to make the first observations of plasma waves and low-frequency radio emissions in the magnetospheres of the gas giant planets Jupiter, Saturn, Uranus, and Neptune.

Also, data from the instrument enabled Gurnett to discover lightning in the atmospheres of Jupiter and Neptune. In other words, he found out that these planets have something in common with Earth: they have the kind of atmospheric interaction that causes a car radio to crackle and pop during a thunderstorm.

Gurnett didn’t work alone. Assisting him through much of his career has been Bill Kurth, longtime UI research scientist, Plasma Wave co-investigator and co-author of the Science paper, published this week, heralding Voyager 1’s arrival in interstellar space.

Kurth presently serves as principal investigator for the Juno Waves instrument. One of nine instruments carried aboard NASA’s Juno spacecraft, the UI-designed-and-built radio and plasma wave instrument will examine a variety of phenomena within Jupiter’s polar magnetosphere and its auroras when it arrives at the planet in July 2016.

There would be no discoveries without the UI team who helped design and build the Voyager Plasma Wave instrument, beginning in the early 1970s. Indeed, the historic observations made by Voyager 1 would not have been possible without the talents of more than 60 UI faculty, staff, and students.

Voyager is far from having completed its journey, meaning that the next discoveries will have a UI imprint as well.