Space again, dudes and dudettes and this time with pictures.
- Cassini's closest encounters
- Giant cyclones seen on Saturn
- Probe to Examine Our Space in Space
- Giant cyclones seen on Saturn
- Europe aims for re-entry spacecraft
P.S. 20.11 happens to be my birthday, so this publication is my present for me. I looooove space!
Cassini's closest encountersThe Cassini orbiter came through its closest-ever encounter with a Saturnian moon with flying colors - and with a fresh crop of cool black-and-white pictures of Enceladus. The most precious products of Thursday's 16-mile-high pass weren't the pictures, but the samplings of the mysterious stuff welling up from the cracks in Enceladus' icy surface.
The big reason why the 22-foot-high (6.8-meter-high) spacecraft came so close to Enceladus (25 kilometers, for the metrically inclined) was to collect samples of dust and other material given off by the moon.
Past flybys confirmed that water ice crystals and even organic molecules were emanating from geysers on the surface. During Thursday's encounter, scientists wanted to get closer-in samples, in hopes of pinpointing which materials were coming from where. Cassini's dust analyzer is tailor-made for such observations.
Due to a software glitch, "this particular instrument had a little bit of a hiccup the last time we tried to make this measurement," said Pappalardo, a planetary scientist at NASA's Jet Propulsion Laboratory. But the detector apparently worked like a charm this week.
He compared the plume of ice and other materials to a hand reaching out from Enceladus itself. "Instead of seeing the 'fist,' we're seeing the fingers now," he said.
The dust analyzer should be able to tell scientists more precisely what's inside the jets of material given off by the geysers. It's tempting to think that the results could point to a "smoking gun" for life beneath Enceladus' surface - but that's a tall order. For now, Pappalardo is just happy to hear that Cassini has done its part.
"There is data in hand now," he said.
There are pictures in hand as well, and some of them have already been posted to the Cassini imaging team's Web site.
"The imaging team acquired fabulous images," Carolyn Porco of the Colorado-based Space Science Institute said in an e-mailed status report, "and the instruments designed to collect and measure the constituents of the plume for analysis did what they should."
The raw black-and-white images provide another good look at the moon's cracked and craggy surface. And the next flyby, a 122-mile-high (197-kilometer-high) pass scheduled for Oct. 31, should serve up some tasty Halloween treats for Porco and her team.
"That one is designed for imaging," she said. source
My comment:Nice, click on the links or the source to see the beautiful pictures. Though I'm much more happy about the data from the moon itself. It's great to be able to get samples, especially when Nature offers them so kindly to us by making them fly around the moon. I can't wait for the analysis.
Giant cyclones seen on Saturn
Storms are 'hundreds of times stronger' than most hurricanes on Earth
NASA/JPL/University of Arizona
These two infrared images of Saturn show the entire south polar region with the hurricane-like vortex in the center.
Scientists have discovered a giant cyclone swirling on Saturn's north pole, and observed a similar storm on the planet's south pole in detail 10 times greater than before, thanks to new images from NASA's Cassini spacecraft.
The new images, taken in infrared light, reveal for the first time a massive cyclone churning at the north pole, similar to a gigantic storm on Saturn's south pole.
"These are truly massive cyclones, hundreds of times stronger than the most giant hurricanes on Earth," said Kevin Baines, Cassini scientist on the visual and infrared mapping spectrometer at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Dozens of puffy, convectively formed cumulus clouds swirl around both poles, betraying the presence of giant thunderstorms lurking beneath. Thunderstorms are the likely engine for these giant weather systems."
Researchers think the storms are powered by heat released from condensing water in thunderstorms deep down in the atmosphere, similar to the way condensing water in clouds on Earth powers hurricane vortices.
But unlike Earth's hurricanes, which stem from the ocean's heat and water, Saturn's cyclones have no body of water at their bases. The storms on that planet are locked to Saturn's poles, whereas terrestrial hurricanes drift across the ocean.
Cassini mapped the entire north pole of Saturn in detail in infrared, with features as small as 120 kilometers (75 miles) visible in the images. Time-lapse movies of the clouds circling the north pole show the whirlpool-like cyclone there is rotating at 325 mph (530 kph) — more than twice as fast as the highest winds measured in cyclones on Earth.
Surrounding the cyclone is an odd, honeycomb-shaped hexagon, which itself does not seem to move while the clouds within it whip around at high speeds. Strangely, neither the fast-moving clouds inside the hexagon nor the cyclone seem to disrupt the six-sided feature.
The cyclone on Saturn's south pole has been observed before, but never in as much detail. Earlier images revealed an outer ring of high clouds surrounding a region previously thought to be mostly clear air interspersed with a few puffy clouds circulating around the center. The new images show that the clouds are actually vigorous convective storms that form yet another distinct, inner ring.
The outer ring of high clouds around the vortex is 2,500 miles (4,000 kilometers) wide, and its clouds cast shadows, indicating they are 25 to 45 miles (40 to 70 km) above the clouds inside the ring. The new images hint at an inner ring about half the diameter of the main ring, and so the actual clear "eye" region is smaller than it appeared in earlier low-resolution images.
The Cassini-Huygens mission, which has been in orbit around Saturn since July 2004, is a collaboration between NASA, the European Space Agency and the Italian Space Agency.
My comment: Ok, that is absolutely stunning, specifically the honeycomb structure. Isn't this driving up your wildest dreams?! Ok, I probably read too much science fiction, but it's amazing what opportunities planets like Saturn and Jupiter offer to life. There is water, its composition is mostly hydrogen and helium, but there is also ice of ammonia, ice of methane and water ice. a link. Methane is pretty well know for its role in organic life. Not to forget the fact that Saturn emits more twice more energy in the infrared than it receives from the Sun. Now, this could have very physical explanation, now that I think, but it could have a biological one. I mean this is a huge "ocean" of stuff we can't even see! And this storm? Hmmm. I'm saying there is definitely something special here and I'll love to see more data coming.
Probe to Examine Our Space in Space
Irene Klotz, Discovery News
The Heliosphere | Video: Discovery Space
Oct. 13, 2008 -- As the solar system carts around our little section of the Milky Way galaxy, it disturbs the relative calm and cold fabric of intergalactic space. Not much is known about this boundary, except that the meeting is far from sedate -- something akin to a boat slamming through water at 50,000 mph.
So far, only the Voyager probes have crossed into the boundary zone, some eight to nine billion miles from Earth, with surprising results. On Sunday, NASA plans to launch a spacecraft that for the first time will be able to map the zone -- without having to go there.
The spacecraft is known as the Interstellar Boundary Explorer, or IBEX. It works by detecting particles that were stripped of electric charges in the outer regions of the heliosphere, the solar wind-filled bubble that delineates our solar system from intergalactic space.
The particles are called energetic neutral atoms and they were discovered accidentally about 20 years ago during a mission that studied the Earth's magnetosphere and the solar wind. Instruments on the satellites to measure what should have been low background levels of energetic particles sometimes detected extra counts.
Scientists learned that these energetic neutral atoms were being generated from inside the magnetosphere and realized a similar process would occur from the solar system's magnetic bubble as well.
The neutral atoms are created when a neutral atom from interstellar space passes a positively-charged particle from the sun. When this happens, an electron can jump from one to the other, making the charged atom neutral.
The next challenge was to figure out how to put a spacecraft far enough away from Earth's magnetic field so it could find the atoms transformed by the solar system's passage through intergalactic space.
With a budget of $169 million, scientists had limited options for launchers. They settled on a low-cost Pegasus booster, an air-launched system created by Orbital Sciences Corp., and outfitted IBEX with a hydrazine-fueled rocket motor that can place it into an orbit that reaches a distance nearly as far from Earth as the moon.
Two-thirds of the 1,000-pound spacecraft is fuel.
IBEX will take several weeks to maneuver into position before mapping can begin. Each full-sky survey will take six months. IBEX currently is funded for two years.
Among the mission's goals are to determine how the environment may have changed over time. For example, scientists are interested in learning if galactic cosmic rays were more prevalent in the past, as higher bursts of radiation may have impacted evolution.
NASA's Voyager probes were dispatched in the 1970s to survey the outer planets. Voyager 1 crossed an area known as the termination shock, the boundary region between the solar system and the intergalactic medium in 2004. Voyager 2 followed in 2007.
Both probes are headed toward the outer boundary of the solar system known as the heliopause, which is where the sun's influence ends and interstellar space begins.
So far, scientists have learned that there are cosmic rays being produced from somewhere in the heliosphere that are not coming from nova and supernova explosions and that heliosphere is not uniformly shaped. Voyager 2 hit the termination shock nearly a billion miles sooner than Voyager 1.
"Maybe there's stronger-than expected magnetic fields on the outside pushing (the heliosphere) in on the south side," McComas said. "The whole region may be deflated. Nobody ever thought we could cross that much closer in with Voyager 2."
IBEX's launch is set for Sunday from the Kwajalein Atoll, located on the Marshall Islands in the Pacific Ocean. That location is closer to the equator than mainland U.S. launch sites, which will enable the rocket to take maximum advantage of Earth's rotational spin and leave the satellite in as high an altitude as possible.source
My comment: Ok, isn't this article mind-blowing you? Just like a blow-job but on the mind. It works for me :) Even the sound of "intergalactic medium" thrills me. Living our everyday life, we simply don't realise how VAST the Universe is and how small we are comparing to everything around us. Too bad our engines are still so sucky, we can't mount decent missions to that region. I don't get it how engeners can sleep knowing what has to be done and that it's still not done!
Europe aims for re-entry spacecraft
Spacecraft designed to use rear flaps in a paddling motion to steer itself
By Jeremy Hsu
Oct. 15, 2008
Plenty of European astronauts and hardware have gone up to the space station or to other orbits around Earth, but now the European Space Agency is thinking of ways to get them back down on their own.
A Vega rocket on the drawing boards is slated to carry ESA's Intermediate eXperimental Vehicle into space in 2012. The stubby white-and-black spacecraft is designed to use two rear flaps in a paddling motion to steer itself during atmospheric reentry.
Such a demonstration craft could perhaps pave the way for Europe to return its astronauts to Earth without relying on the U.S. or Russian space programs. The Unites States itself faces a four-year gap in manned spaceflight capability after the space shuttle retires in 2010, and will have to rely on the Russian Soyuz spacecraft.
"With ATV [Automated Transfer Vehicle] and Columbus, the European space laboratory, we believe Europe has now become one of the major players in manned space exploration," said John Ellwood, ATV mission manager. He added that the European Union's Council of Ministers would meet in November to set space policy for the next several years.
Europe's ATV currently serves as an unmanned space delivery vehicle, with the first, named Jules Verne, successfully completing its mission and undergoing a fiery death in the Earth's atmosphere. But now ESA wants to push forward with developing an ATV variant that could undergo re-entry and safely return cargo or astronauts.
"ESA does not plan to develop a reusable re-entry system on the basis of the ATV, but rather an expendable re-entry vehicle," said Marco Caporicci, head of transport and re-entry systems for the ESA Human Spaceflight Directorate.
The Advanced Re-entry Vehicle would use Europe's Ariane 5 rocket, which is not reusable. An expendable service module would boost the ARV into orbit and guide the re-entry module to reenter Earth's atmosphere.
ESA has not tried to develop a reusable launch system or service module because of the low number of European spaceflights, Caporicci said. But the re-entry capsule would conceptually resemble NASA's Apollo or upcoming Orion capsules, with some changes.
"We believe that the shape selected, with a cone angle of 20 degrees, would allow more internal volume than for the classical Apollo shape," Caporicci told Space.com.
Caporicci cautioned that "ARV does not play a role in closing the gap between Shuttle and Orion," and that the IXV and ARV programs would each follow their own separate development tracks.
© 2007 Space.com. All rights reserved. More from Space.com. source
My comment: Ok, I don't like one-time-use things and when it comes down to a spacecraft I like them even less. But it's a good beginning, even if you think of it as an emergency fly-down. Because I get creeped when I think of those astronauts, stuck in the middle of nothing, without a way to get home in case something goes wrong. It's even more amazing how nothing went wrong so far, not that I wish that for them. I wish them only luck, because they deserve it. My point-I cheer the European initiative and hope that the usual lack of money will turn out to become a great simplistic craft that could eventually become reusable.