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:
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.
The weather forecast for Titan? Cloudy, hazy, and cold — just like every other day! The image here is a color-composite made from raw data captured by Cassini during a flyby on April 7, 2014, and it shows a look at the two main features of Titan’s atmosphere: a thick orange “smog” made of organic compounds created by the breakdown of nitrogen and methane by UV light, and a wispy blue upper-level haze composed of complex hydrocarbons.
Cassini was approximately 19,076 miles (30,700 km) from Titan when these particular images were captured.
Mars wasn’t always the cold, dry world that it is today — billions of years ago it likely looked a lot more like Earth, with seas and rivers of liquid water on its surface and a thick atmosphere with air and clouds. But something happened over the course of Mars’ history to transform it from a warm, wet world to a cold, desiccated desert planet, and while there are many viable suggestions as to what process is responsible, no verdict has yet been delivered.
This video, just released by NASA’s Goddard Space Flight Center, shows what Mars might have looked like four billion years ago. As the camera tracks back the clouds gradually disappear, the lakes and rivers turn to rubble-strewn plains and the skies change from blue to pale orange. As we rise above the dust clouds that roll across the planet, we see the first evidence of modern times: NASA’s MAVEN spacecraft, flying high overhead to investigate the mystery of a lost Mars.
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Saturn might look like a placid beige ball in backyard telescopes but in reality it has very dynamic weather patterns and climates, rivaling the storms of Jupiter and the varied climates of Earth, based on long-term microwave observations by the Cassini spacecraft.
(Yes, microwaves are good for much more than heating up your coffee.)
Scientists working with data from NASA’s Cassini mission have confirmed the presence of a population of complex hydrocarbons in the upper atmosphere of Saturn’s largest moon, Titan, that later evolve into the components that give the moon a distinctive orange-brown haze. The presence of these complex, ringed hydrocarbons, known as polycyclic aromatic hydrocarbons (PAHs), explains the origin of the aerosol particles found in the lowest haze layer that blankets Titan’s surface. Scientists think these PAH compounds aggregate into larger particles as they drift downward.
“With the huge amount of methane in its atmosphere, Titan smog is like L.A. smog on steroids.”
– Scott Edgington, Cassini deputy project scientist