This processed picture of Io by New Horizons reveals the 290-kilometer-high (180-mile-high) plume of the volcano Tvashtar near Io’s north pole. Also noticeable is the Prometheus volcano’s much smaller sized plume in the 9 o’clock instructions. The top of the Masubi volcano’s plume looks like an irregular intense spot near the bottom. Credit: NASA/JHUAPL/SwRI
The Juno Waves instrument “listened” to the radio emissions from Jupiter’s enormous electromagnetic field to discover their exact areas.
By listening to the rain of electrons streaming onto Jupiter from its extremely volcanic moon Io, scientists utilizing NASA’s Juno spacecraft have actually discovered what sets off the effective radio emissions within the beast world’s enormous electromagnetic field. The brand-new outcome clarifies the habits of the huge electromagnetic fields produced by gas-giant worlds like Jupiter.
Jupiter has the biggest, most effective electromagnetic field of all the worlds in our planetary system, with a strength at its source about 20,000 times more powerful than Earth’s. It is buffeted by the solar wind, a stream of electrically charged particles and electromagnetic fields continuously blowing from the Sun. Depending on how difficult the solar wind blows, Jupiter’s electromagnetic field can extend external as much as 2 million miles (3.2 million kilometers) towards the Sun and extend more than 600 million miles (over 965 million kilometers) far from the Sun, as far as Saturn’s orbit.
The various colored lines in this conceptual image represent the electromagnetic field lines that connect Io’s orbit with Jupiter’s environment. Radio waves emerge from the source and propagate along the walls of a hollow cone (gray location). Juno, its orbit represented by the white line crossing the cone, gets the signal when Jupiter’s rotation sweeps that cone over the spacecraft. Credit: NASA/GSFC/Jay Friedlander
Jupiter has numerous big moons that orbit within its huge electromagnetic field, with Io being the closest. Io is captured in a gravitational tug-of-war in between Jupiter and the surrounding 2 of these other big moons, which creates internal heat that powers numerous volcanic eruptions throughout its surface area.
These volcanoes jointly launch one lots of product (gases and particles) per 2nd into area near Jupiter. Some of this product breaks up into electrically charged ions and electrons and is quickly caught by Jupiter’s electromagnetic field. As Jupiter’s electromagnetic field sweeps past Io, electrons from the moon are sped up along the electromagnetic field towards Jupiter’s poles. Along their method, these electrons create “decameter” radio waves (so-called decametric radio emissions, or DAM). The Juno Waves instrument can “listen” to this radio emission that the drizzling electrons create.
Juno tunes into among its preferred radio stations. Hear the decametric radio emissions activated by the interaction of Io with Jupiter’s electromagnetic field. The Waves instrument on Juno identifies radio signals whenever Juno’s trajectory crosses into the beam which is a cone-shaped pattern. This beam pattern resembles a flashlight that is just giving off a ring of light instead of a complete beam. Juno researchers then equate the radio emission discovered to a frequency within the audible variety of the human ear. Credit: University of Iowa/SwRI/NASA
The scientists utilized the Juno Waves information to recognize the exact areas within Jupiter’s huge electromagnetic field where these radio emissions came from. These areas are where conditions are ideal to create the radio waves; they have the ideal magnetic field strength and the right density of electrons (not excessive and not insufficient), according to the group.
“The radio emission is likely constant, but Juno has to be in the right spot to listen,” stated Yasmina Martos of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and the University of Maryland, College Park.
The radio waves emerge from the source along the walls of a hollow cone lined up with and managed by the strength and shape of the electromagnetic field of Jupiter. Juno gets the signal just when Jupiter’s rotation sweeps that cone over the spacecraft, in the exact same method a lighthouse beacon shines briefly upon a ship at sea. Martos is lead author of a paper about this research study released in June 2020 in the Journal of Geophysical Research, Planets.
Data from Juno permitted the group to determine that the energy of the electrons producing the radio waves was far greater than formerly approximated, as much as 23 times higher. Also, the electrons do not always require to come from a volcanic moon. For example, they might be in the world’s electromagnetic field (magnetosphere) or originated from the Sun as part of the solar wind, according to the group.
Reference: “Juno Reveals New Insights Into Io-Related Decameter Radio Emissions” by Yasmina M. Martos, Masafumi Imai, John E. P. Connerney, Stavros Kotsiaros and William S. Kurth, 18 June 2021, Journal of Geophysical Research, Planets.
DOI: 10.1029/2020JE006415
More about this task and the Juno Mission
The research study was moneyed by the Juno Project under NASA Grants NNM06AAa75c and 699041X to the Southwest Research Institute in San Antonio, Texas, and NASA Grant NNN12AA01C to NASA’s Jet Propulsion Laboratory, a department of Caltech in Pasadena, California. The group is made up of scientists from NASA Goddard, the National Institute of Technology (KOSEN) in Tokyo, Japan; Niihama College in Niihama, Ehime, Japan, the University of Iowa, Iowa City; and the Technical University of Denmark in Kongens Lyngby, Denmark. NASA JPL handles the Juno objective for the primary private investigator, Scott J. Bolton, of the Southwest Research Institute. Juno belongs to NASA’s New Frontiers Program, which is handled at NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the firm’s Science Mission Directorate in Washington. Lockheed Martin Space in Denver developed and runs the spacecraft.
