It’s the signature accessory of the largest planet in our solar system: Jupiter’s Great Red Spot, an enormous anticyclone over twice the width of our entire planet. Visible in even modest backyard telescopes, the GRS has been churning away for at least several hundred years. But, based on recent analysis of data gathered by the Cassini spacecraft during its pass by Jupiter in December 2000, the Great Red Spot’s rusty coloration may actually only be skin-deep – a “sunburn” created by interaction between Jupiter’s upper atmosphere and solar radiation.
Out in the depths of our solar system, about 1.8 billion miles away from the Sun somewhere between the planets Saturn and far-flung Neptune, orbits the oddball ice giant Uranus – a frigid, thinly-ringed world tipped almost completely on its side and shrouded in both mystery and pale blue-green clouds. Aside from the occasional bright storm clouds spotted along the planet’s mid-latitudes and the even rarer darker blue storms, Uranus’ atmosphere has proven to be remarkably featureless… especially around its high southern latitudes.
Now, astronomer Erich Karkoschka from the University of Arizona has used imagery from Voyager 2′s 1986 visit to Uranus to bring out some visible features in the planet’s skies by using pattern recognition software to map out even the most subtle differences, and then boosting the contrast to make them more apparent. What he’s found are atmospheric anomalies that hint at curious structures in the planet’s dense core far beneath.
Watch a very cool animation below showing the new details Karkoschka has teased out of 29-year-old Voyager 2 data:
If you’re loving this fantastic image of the Red Planet as much as I am, then be sure to give thanks to MOM!
Don’t call home just yet though; this is a view from India’s Mars Orbiter Mission – MOM for short – which successfully entered orbit around Mars on September 24 after a ten-month journey to meet up with our neighboring planet.
(Of course if you want to call your own mom I’m sure she’d love to hear your voice.)
Whether you think Pluto is a planet, a dwarf planet, a Kuiper Belt Object – or something else entirely – you should still be fascinated by this: a video of the dwarf planet Pluto and its largest moon Charon showing the two distinctly separate worlds actually in motion around each other! Captured by the New Horizons spacecraft from July 19–24, the 12 images that comprise this animation were acquired with the Long Range Reconnaissance Imager (LORRI) instrument from distances of 267 million to 262 million miles (429 million to 422 million km) and show nearly a full orbital rotation. Amazing!
Wrapped in an atmosphere tinted pale blue by high-altitude methane, Uranus has occasionally been observed to develop large storms in its frigid windy skies. NASA’s Voyager 2 saw a few small storm clouds spotting Uranus during its flyby in Jan. 1986, and more recently some large but short-lived storms were observed by Hubble and the W.M. Keck Observatory as the planet moved toward its equinox in 2007. Now, seven years after its equinox, swirling storms are once again blooming on Uranus — and Keck astronomers have caught them on camera (while preparing for terrestrial hurricanes to make landfall!)
Having made over 3,000 orbits of Venus over the past eight years, ESA’s Venus Express has (as of May 15) completed its science mission and is now in the final few months of its operational life. With a nothing-left-to-lose attitude, the spacecraft recently made a daring and risky dive down into the upper layers of the planet’s thick atmosphere, coming within 80 miles of Venus’ broiling surface on July 12 — that’s the closest any human-made spacecraft have gotten to Venus since the Soviet Vega balloon-and-lander missions of 1985!
As dangerous as it may have been for the spacecraft, Venus Express survived the encounter and grabbed some valuable data about the planet’s atmosphere along the way. It’s now working its way up to a higher altitude orbit, but there’s no escaping the fact that its fuel reserves are nearly depleted and it will soon be back on its way down into Venus’ atmosphere on a mission-ending, one-way trip.
Just a week after Curiosity celebrated its first Martian year in Gale Crater and we have yet another milestone anniversary in Solar System exploration: as of 10:48 p.m. EDT tonight Cassini will have been in orbit around Saturn for a full decade!
“There are times when human language is inadequate, when emotions choke the mind, when the magnitude of events cannot properly be conveyed by the same syllables we use to navigate everyday life. The evening of June 30, 2004 was such a time.”
– Carolyn Porco, Cassini Imaging Team Leader, CICLOPS “Captain’s Log” on June 30, 2014
That’s ten years and over 2 billion miles of discoveries and explorations of our Solar System’s most majestic planet and its incredibly varied family of moons. Over the course of its primary mission and three extended missions, we have been able to get a close-up look at Saturn and its moons like never before, witnessing first-hand the changes that occur as their seasons change. What’s been discovered by the Cassini mission about Saturn has offered invaluable insight into the evolution of our entire Solar System, as well as planets that could be found elsewhere in our galaxy.
“Having a healthy, long-lived spacecraft at Saturn has afforded us a precious opportunity,” said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory in Pasadena, California. “By having a decade there with Cassini, we have been privileged to witness never-before-seen events that are changing our understanding of how planetary systems form and what conditions might lead to habitats for life.”
Launched on October 15, 1997, the Cassini-Huygens spacecraft established orbit around Saturn on June 30, 2004 (July 1, UTC).