Cassini spacecraft gets close-up of huge Saturn storm

NASA JPL releases imagery from the Cassini  probe showing a huge hurricane circulating around Saturn’s north pole:

NASA Probe Gets Close-Up Views of Large Hurricane on Saturn

PASADENA, Calif. – NASA’s Cassini spacecraft has provided scientists the first close-up, visible-light views of a behemoth hurricane swirling around Saturn’s north pole.

In high-resolution pictures and video, scientists see the hurricane’s eye is about 1,250 miles (2,000 kilometers) wide, 20 times larger than the average hurricane eye on Earth. Thin, bright clouds at the outer edge of the hurricane are traveling 330 mph(150 meters per second). The hurricane swirls inside a large, mysterious, six-sided weather pattern known as the hexagon.

“We did a double take when we saw this vortex because it looks so much like a hurricane on Earth,” said Andrew Ingersoll, a Cassini imaging team member at the California Institute of Technology in Pasadena. “But there it is at Saturn, on a much larger scale, and it is somehow getting by on the small amounts of water vapor in Saturn’s hydrogen atmosphere.”

Scientists will be studying the hurricane to gain insight into hurricanes on Earth, which feed off warm ocean water. Although there is no body of water close to these clouds high in Saturn’s atmosphere, learning how these Saturnian storms use water vapor could tell scientists more about how terrestrial hurricanes are generated and sustained.

Both a terrestrial hurricane and Saturn’s north polar vortex have a central eye with no clouds or very low clouds. Other similar features include high clouds forming an eye wall, other high clouds spiraling around the eye, and a counter-clockwise spin in the northern hemisphere.

A major difference between the hurricanes is that the one on Saturn is much bigger than its counterparts on Earth and spins surprisingly fast. At Saturn, the wind in the eye wall blows more than four times faster than hurricane-force winds on Earth. Unlike terrestrial hurricanes, which tend to move, the Saturnian hurricane is locked onto the planet’s north pole. On Earth, hurricanes tend to drift northward because of the forces acting on the fast swirls of wind as the planet rotates. The one on Saturn does not drift and is already as far north as it can be.

“The polar hurricane has nowhere else to go, and that’s likely why it’s stuck at the pole,” said Kunio Sayanagi, a Cassini imaging team associate at Hampton University in Hampton, Va.

Scientists believe the massive storm has been churning for years. When Cassini arrived in the Saturn system in 2004, Saturn’s north pole was dark because the planet was in the middle of its north polar winter. During that time, the Cassini spacecraft’s composite infrared spectrometer and visual and infrared mapping spectrometer detected a great vortex, but a visible-light view had to wait for the passing of the equinox in August 2009. Only then did sunlight begin flooding Saturn’s northern hemisphere. The view required a change in the angle of Cassini’s orbits around Saturn so the spacecraft could see the poles.

“Such a stunning and mesmerizing view of the hurricane-like storm at the north pole is only possible because Cassini is on a sportier course, with orbits tilted to loop the spacecraft above and below Saturn’s equatorial plane,” said Scott Edgington, Cassini deputy project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “You cannot see the polar regions very well from an equatorial orbit. Observing the planet from different vantage points reveals more about the cloud layers that cover the entirety of the planet.”

Cassini changes its orbital inclination for such an observing campaign only once every few years. Because the spacecraft uses flybys of Saturn’s moon Titan to change the angle of its orbit, the inclined trajectories require attentive oversight from navigators. The path requires careful planning years in advance and sticking very precisely to the planned itinerary to ensure enough propellant is available for the spacecraft to reach future planned orbits and encounters.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology, Pasadena, manages the Cassini-Huygens mission for NASA’s Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team consists of scientists from the United States, the United Kingdom, France and Germany. The imaging operations center is based at the Space Science Institute in Boulder, Colo.

Images and two versions of a movie of the hurricane can be viewed online at: http://go.nasa.gov/17tmHzo .

For more information about Cassini and its mission, visit: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov .

Copenhagen Suborbitals: The Sapphire guided rocket

Copenhagen Suborbitals posted this video today. It gives a description of the guidance and control system of Copenhagen Suborbitals Sapphire rocket.

http://youtu.be/g4nz4SfCbek

The latest CS newsletter also included this item about the Sapphire rocket:

The entire crew of Copenhagen Suborbitals are working hard these days. Summer is coming and in a short time we will attempt to launch our first actively guided rocket “Sapphire”. Sapphire is a test vehicle. It’s only purpose is to verify that our guidance software and control systems work.

As mentioned before the Sapphire rocket is not built to reach space – but will give us invaluable information on active guidance and how to control a rocket in flight. We will use the test results to evaluate and upscale the guidance system so it can be used to guide our bigger rockets that are already in production.

The launch window for Sappire will be announced very shortly. As always we will provide a live and commented video feed of the launch. While you wait we have compiled this second video where Lead Guidance Officer Flemming Nyboe explains how Sapphire’s guidance system works.

Update: Kristian von Bengtson writes more about their plans for Sapphire: Full Time Preparations for Launching the Sapphire – and Happy Hour at Copenhagen Suborbitals – Wired Science/Wired.com.

Sci-Tech: New techniques could greatly boost solar power

Here are reports on two potential big improvements in solar power collection.

Nanometer sized antennas could convert a much wider range of the solar spectrum into useful electric power  than conventional solar cells (via CitizensInSpace.org):

And a new paper in Science reports on a technique to hurdle over a fundamental barrier to the efficiency of photons creating free electrons in solar cells: New solar cell coating could boost efficiency – R&D Magazine.

The Space Show this week

Here is the list of guests for The Space Show this week:

1. Monday, April 29, 2013, 2-3:30 PM PST (5-6:30 PM EST, 4-5:30 PM CST): ED WRIGHT joins us for Citizens in Space updates and info about the upcoming Space Hacker Workshop in Silicon Valley: http://spacehacker.eventbrite.com/#.

2. Tuesday, April 30, 2013 2013, 7-8:30 PM PST (10-11:30 PM EST, 9-10:30 PM CST): Retired astronaut JERRY ROSS is with us to discuss his new book, Spacewalker.

3. Friday, May 3: , 2013, 9:30-11 AM PST (11:30- 1 PM CST, 12:30PM-2:00 PM EST): As of press time, our guest for this program is yet to be determined but will either be DR. SARAH CRUDDAS of the UK or FRANK STRATFORD from Australia. We are awaiting final scheduling requirements. Please check the website newsletter for guest details and any program time changes for this Friday program. You can find the website newsletter at www.thespaceshow.com/newsletterfinal.htm.

4. Sunday, May 5, 2013, 12-1:30 PM PST (3-4:30 PM EST, 2-3:30 PM CST). We welcome HU DAVIS AND BILL KETCHUM to the show to discuss space policy, SSP [Space Solar Power], and much more, all from two highly regarded and well respected space veterans.
See also:
/– The Space Show on Vimeo – webinar videos
/– The Space Show’s Blog – summaries of interviews.
/– The Space Show Classroom Blog – tutorial programs

The Space Show is a project of the One Giant Leap Foundation.