For years, scientists have puzzled over inexplicable variations in the timing of those radio pulsations. Now, the new-found aurora behaviour may offer a vital clue to what is going on.
“This is an important discovery because it provides a long-suspected, but hitherto missing, link between the radio and auroral emissions,” said Jonathan Nichols, a physics and astronomy researcher at the University of Leicester who led the study.
Saturn, like other magnetized planets, emits radio waves into space from the polar regions. These radio emissions pulse with a period near to 11 hours, and the timing of the pulses was originally thought to represent the rotation of the planet. However, over the years since the Voyager satellite missions, which flew past Saturn in 1980 and 1981, the period of the pulsing of the radio emissions has varied. Since the rotation of a planet cannot be easily sped up or slowed down, the hunt for the source of the varying radio period has become one of the most perplexing puzzles in planetary science.
Now, in a paper to be published in Geophysical Research Letters, a publication of the American Geophysical Union, the researchers use images from the NASA/ESA Hubble Space Telescope of Saturn’s auroras obtained between 2005-2009 to show that the auroras pulse in tandem with the radio emissions.
Auroras, known as the northern and southern lights on Earth, are caused when charged particles in space are funnelled along a planet’s magnetic field into the planet’s upper atmosphere near the poles, whereupon they impact the atmosphere, causing them to glow. This happens when a planet’s magnetic field is stressed by, for example, the buffeting from the stream of particles emitted by the Sun, or when moons such as Enceladus or Io expel material into the near-planet space.
Saturn’s radio waves were long suspected to be emitted by the charged particles as they hurtle toward the poles, but no radio-like pulsing had been observed in Saturn’s aurora.
However, Nichols and his colleagues found that by using the timing of the radio pulses as a guide to organizing auroral data, and by stacking the results from all the Hubble Saturn auroral images from 2005-2009 on top of each other, the auroral pulses finally revealed themselves.
“This link is important since it implies that the pulsing of the radio emissions is being imparted by the processes driving Saturn’s aurora, which in turn can be studied by the NASA/ESA spacecraft Cassini, presently in orbit around Saturn,” Nichols said. “It thus takes us a significant step toward solving the mystery of the variable radio period.”Title:
Kathleen O’Neil | University of Leicester
Astronomers find unexpected, dust-obscured star formation in distant galaxy
24.03.2017 | University of Massachusetts at Amherst
Gravitational wave kicks monster black hole out of galactic core
24.03.2017 | NASA/Goddard Space Flight Center
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy