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.
Image credit: NASA/JPL-Caltech/SSI
13 Must See Stargazing Events for 2013
— Listed In Chronological Order
1) January 21 — Very Close Moon/Jupiter Conjunction
A waxing gibbous moon (78% illuminated) will pass within less than a degree to the south of Jupiter high in the evening sky. Your closed fist held out at arms length covers 10 degrees. These two wont get that close again until 2026.
2) February 2-23 — Best Evening View of Mercury
The planet Mercury will be far enough away from the glare of the Sun to be visible in the Western sky after sunset. It will be at its brightest on the 16th and dim quickly afterwards. On the 8th it will skim by the much dimmer planet Mars by about 0.4 degrees.
3) March 10-24 — Comet PANSTARRS at its best
First discovered in 2011, this comet should be coming back around for about 2 weeks. It will be visible low in the northwest sky after sunset. Here are some sources predicting what the comets may look like in the sky;
1 - http://bit.ly/Trh0wM
2 - http://bit.ly/WebniW
4) April 25 — Partial Lunar Eclipse
A very minor, partial lunar eclipse (not visible in North America) where only about 2 percent of the moon’s diameter will be inside the dark shadow of the Earth.
5) May 9 — Annular Eclipse of the Sun (“Ring of Fire” Eclipse)
It will be visible in Northern Australia and parts of Papua New Guinea but mostly within the Pacific Ocean. See all the solar eclipse paths for 2001-2020 here.
6) May 24-30 — Dance of the Planets
Mercury, Venus and Jupiter will seemingly dance between each other in the twilight sky just after sunset as they will change their positions from one evening to the next. Venus will be the brightest of all, six times brighter than Jupiter.
7) June 23 — Biggest Full Moon of 2013
It will be the biggest full moon because the moon will be the closest to the Earth at this time making it a ‘supermoon’ and the tides will be affected as well creating exceptionally high and low tides for the next few days.
8) August 12 — Perseid Meteor Shower
One of the best and most reliable meteor showers of the year producing upwards of 90 meteors per hour provided the sky is dark. This year the moon won’t be in the way as much as it will set during the evening leaving the rest of the night dark. Here is a useful dark-sky finder tool. - http://bit.ly/UdcDUY
9) October 18 — Penumbral Eclipse of the Moon
Visible mostly in Asia, Europe and Africa, at this time the 76% of the moon will be covered by the penumbral shadow of the Earth.
10) November 3 — Hybrid Eclipse of the Sun
A Hybrid Eclipse meaning, along its path, the eclipse will turn from Annular to Total and in this case most of the path will appear to be Total as there will be a slight ring of sunlight visible near the beginning of the track. This one will begin in the Atlantic (near the East Coast of the U.S.) and travel through Africa. The greatest eclipse (with 100 seconds of totality) will appear in Liberia, near the West Coast of Africa.
Eclipse Path - http://1.usa.gov/VrJggj
11) Mid-November through December — Comet ISON
The second comet this year, ISON, could potentially be visible in broad daylight as it reaches its closest point to the Sun. It will reach that point on November 28 and it is close enough to the Sun to be categorized as a ‘Sungrazer’. Afterwards it will travel towards Earth (passing by within 40 million miles) a month later.
12) All of December — Dazzling Venus
The brightest planet of them all will shine a few hours after sundown in the Southwestern sky and for about 1.5 hours approaching New Years Eve. Around December 5th, a crescent moon will pass above the planet and the next night Venus will be at its brightest and wont be again until 2021.
13) December 13-14 — Geminid Meteor Shower
This is another great (if not the best) annual meteor shower. This year put on a show at about 120 meteors per hour and in 2013 it won’t be much different so expect another fantastic show. However, the moon - as it is a few days before full phase - will be in the way for most of the night obscuring some of the fainter meteors. You might have to stay up in the early morning hours (4am) to catch the all the meteors it has to offer. If you missed 2012’s Geminid Meteor Shower, here are some great photo-sets;
1 - http://bit.ly/UJrbc3
2 - http://bit.ly/RoWGfQ
3 - http://bit.ly/UCADCQ
The past year has seen announcements of some of the most Earth-like planets yet discovered, and even a small planet around one of the two stars in Alpha Centauri, our nearest neighboring star system. But in all of this, there’s been one thing in the back of our minds that has been sitting slightly uncomfortably: 25 light-years away lies Fomalhaut b, a planet that has been the cause of an astronomical altercation.
Fomalhaut b has been reanimated! Read more…
My first recording from the International Space Station. You can hear the slight buzz of the station’s fans in the background.
This is the first original, complete song recorded from space.
I dream of sad working men and women’s songs from alien shores.
I don’t know if you’ve heard, but Curiosity found something “earthshaking” on Mars, but NASA won’t say just yet what it is because they want to make sure their data is correct because this is potentially an unbelievably important find for humanity, and in conclusion, this is a pretty cool time to be alive.
IT FEELS LIKE CHRISTMAS!
is there a betting pool? i bet it’s liquid water! like, maybe some geothermal activity that causes there to be liquid water at the surface.
This Is the Most Detailed Image of the Universe Ever Captured
NASA has just published the most detailed view of the Universe ever taken. It’s called the Extreme Deep Field—or XDF for short. It took ten years of Hubble Space Telescope photographs to make it and it shows some the oldest galaxies ever observed by humans, going 13.2 billion years back in time.
It’s a mindblowing, extremely humbling view. Not only for what it shows, but for what it doesn’t show. While this image contains about 5,500 galaxies, it only displays a tiny part of the sky, a ridiculously small slice of the Universe.
one of the coolest things about this is the size of the actual slice of the sky being used. if you took a 1 millimeter by 1 millimeter piece of paper in your fingers and held it at arm’s length, that’s just about the size of sky this image takes up. the universe is enormous and this image is what really put it in perspective for me.
Individual images taken of Venus in one year to create a full curve. The summer solstice being at the top, winter solstice at the bottom, and equinox where they lines cross.