Date: 9 Oct 2007
New Horizons observed Jupiter and its moons on its long journey to Pluto.
With its Multispectral Visible Imaging Camera (MVIC), half of the Ralph instrument, New Horizons captured several pictures of mesoscale gravity waves in Jupiter's equatorial atmosphere. Buoyancy waves of this type are seen frequently on Earth -- for example, they can be caused when air flows over a mountain and a regular cloud pattern forms downstream. In Jupiter's case there are no mountains, but if conditions in the atmosphere are just right, it is possible to form long trains of these small waves. The source of the wave excitation seems to lie deep in Jupiter's atmosphere, below the visible cloud layers at depths corresponding to pressures 10 times that at Earth's surface. The New Horizons measurements showed that the waves move about 100 m per second faster than surrounding clouds; this is about 25% of the speed of sound on Earth and is much greater than current models of these waves predict. Scientists can "read" the speed and patterns of these waves to learn more about activity and stability in the atmospheric layers below.
What Scientists/Engineers Say About This Image:
"One of my favorite images is New Horizons viewing Jupiter during a global cloud 'upheaval,' where usual thick clouds at the equator had disappeared. This view allowed us to see clear high altitude waves and measure their speed for the first time. This helps us understand motions and structure below the clouds, where we can't usually probe."
--Amy Simon-Miller: Astrophysicist, NASA Goddard Space Flight Center
(Read More of what Amy Simon-Miller has to say about this and other significant events by clicking here.)
Last Update: 29 Feb 2012 (AMB)
Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute