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quote:NASA Spacecraft Fine Tunes Course for Mars Landing 04.10.08
This artist's concept shows NASA's Phoenix spacecraft en route to Mars. Image credit: NASA/JPL-Calech/University of Arizona PASADENA, Calif. -- NASA engineers have adjusted the flight path of the Phoenix Mars Lander, setting the spacecraft on course for its May 25 landing on the Red Planet.
"This is our first trajectory maneuver targeting a specific location in the northern polar region of Mars," said Brian Portock, chief of the Phoenix navigation team at NASA's Jet Propulsion Laboratory in Pasadena, Calif. The mission's two prior trajectory maneuvers, made last August and October, adjusted the flight path of Phoenix to intersect with Mars.
NASA has conditionally approved a landing site in a broad, flat valley informally called "Green Valley." A final decision will be made after NASA's Mars Reconnaissance Orbiter takes additional images of the area this month.
The orbiter's High Resolution Imaging Science Experiment camera has taken more than three dozen images of the area. Analysis of those images prompted the Phoenix team to shift the center of the landing target 13 kilometers (8 miles) southeastward, away from slightly rockier patches to the northwest. Navigators used that new center for planning today's maneuver.
The landing area is an ellipse about 62 miles by about 12 miles (100 kilometers by 20 kilometers). Researchers have mapped more than five million rocks in and around that ellipse, each big enough to end the mission if hit by the spacecraft during landing. Knowing where to avoid the rockier areas, the team has selected a scientifically exciting target that also offers the best chances for the spacecraft to set itself down safely onto the Martian surface.
"Our landing area has the largest concentration of ice on Mars outside of the polar caps. If you want to search for a habitable zone in the arctic permafrost, then this is the place to go," said Peter Smith, principal investigator for the mission, at the University of Arizona, Tucson.
Phoenix will dig to an ice-rich layer expected to lie within arm's reach of the surface. It will analyze the water and soil for evidence about climate cycles and investigate whether the environment there has been favorable for microbial life.
"We have never before had so much information about a Mars site prior to landing," said Ray Arvidson of Washington University in St. Louis. Arvidson is chairman of the Phoenix landing-site working group and has worked on Mars landings since the first successful Viking landers in 1976.
"The environmental risks at landing -- rocks and slopes -- represent the most significant threat to a successful mission. There's always a chance that we'll roll snake eyes, but we have identified an area that is very flat and relatively free of large boulders," said JPL's David Spencer, Phoenix deputy project manager and co-chair of the landing site working group.
Today's trajectory adjustment began by pivoting Phoenix 145 degrees to orient and then fire spacecraft thrusters for about 35 seconds, then pivoting Phoenix back to point its main antenna toward Earth. The mission has three more planned opportunities for maneuvers before May 25 to further refine the trajectory for a safe landing at the desired location.
In the final seven minutes of its flight on May 25, Phoenix must perform a challenging series of actions to safely decelerate from nearly 21,000 kilometers per hour (13,000 mph). The spacecraft will release a parachute and then use pulse thrusters at approximately 914 meters (3,000 feet) from the surface to slow to about 8 kilometers per hour (5 mph) and land on three legs.
"Landing on Mars is extremely challenging. In fact, not since the 1970s have we had a successful powered landing on this unforgiving planet. There's no guarantee of success, but we are doing everything we can to mitigate the risks," said Doug McCuistion, director of NASA's Mars Exploration Program at NASA Headquarters in Washington.
For more information about Phoenix, visit: http://www.nasa.gov/phoenix and http://phoenix.lpl.arizona.edu .
The Phoenix mission is led by Peter Smith of the University of Arizona, Tucson, with project management at JPL and development partnership at Lockheed Martin, Denver. International contributions are provided by the Canadian Space Agency; the University of Neuchatel, Switzerland; the universities of Copenhagen and Aarhus, Denmark; the Max Planck Institute, Germany; and the Finnish Meteorological Institute.
Gaat op en neer met dat nieuws over dat wel of geen leven, wel of geen vloeibaar water en wel of geen ijsquote:Is planeet Mars levendiger dan men denkt?
Een onderzoek dat is uitgevoerd door wetenschappers van de Universiteit van Providence heeft uitgewezen dat het klimaat op onze buurplaneet Mars levendiger is dan men aanvankelijk veronderstelde. Er is namelijk bewijs gevonden voor de recente aanwezigheid van dikke, beweeglijke gletsjers op het oppervlak van de rode planeet. De ontdekking vergroot de kans op het vroegere bestaan van leven op diens oppervlak, omdat het vloeibare water een daarvoor een veilige haven kan zijn.
Enkele miljarden jaren geleden zag het onverstoorde oppervlak van Mars er veel anders uit dan nu het geval is. Maar deze rust werd ruw verstoord door een meteorietinslag, welke ervoor zorgde dat het Martiaanse oppervlak droog kwam te liggen. Men vermoedt dat er vanaf dat moment weinig is gebeurd op onze buurplaneet, al lijken nieuwe beelden die gemaakt zijn van de rode planeet te laten zien dat Mars veel levendiger is dan gedacht. Op de opnamen zijn namelijk structuren zichtbaar die erop duiden dat er recentelijk gletsjers te vinden waren rond de evenaar, welke een dikte hadden van één tot drie kilometer.
Nu bevinden deze ijslagen zich daar niet meer, maar de kans is groot dat de gletsjers daar honderd tot tien miljoen jaar geleden wel te vinden waren. Dat is geologisch gezien gisteren. Met het bewijs voor deze activiteit op zak kan men zeggen dat het klimaat op Mars vaak veranderd, iets dat zomaar opnieuw kan gebeuren. De onderzoekers toonden dit aan met behulp van foto's die zijn genomen door NASA's Mars Reconnaissance Orbiter, welke een laaggelegen ravijn in kaart heeft kunnen brengen dat in het bezit is van stenen die laten zien waar de rand van één van de vroegere gletsjers zich bevond. (Science Daily)
Nou, de phoenix kan het allemaal lekker uitzoeken!quote:Op zaterdag 26 april 2008 13:30 schreef Frutsel het volgende:
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Gaat op en neer met dat nieuws over dat wel of geen leven, wel of geen vloeibaar water en wel of geen ijs
http://archive.salon.com/people/feature/2000/08/17/lovelock/quote:He first conceived the Gaia hypothesis while working at the Jet Propulsion Laboratory in Pasadena, Calif., in the mid-1960s, where he was designing life detection instruments for NASA's Mars Viking probes.
How, Lovelock asked himself, if he were on Mars, could he tell there was life on Earth? By the Earth's atmosphere, which defies all natural expectations. Free oxygen accounts for 20 percent of the atmosphere, when the laws of chemistry say that this highly reactive gas should combine and settle down. How fortunate for life, most of which depends on oxygen for survival.
Lovelock concluded that life -- microbes, plants and animals constantly metabolizing matter into energy, converting sunlight into nutrients, emitting and absorbing gas -- is what causes the Earth's atmosphere to be so, well, lively. By contrast, the Martian atmosphere is essentially dead, settled into a low-energy equilibrium with little or no chemical reactions. So he recommended that NASA save its money and scrub the Viking mission. Carl Sagan, his officemate, did not agree but Sagan's then wife, microbiologist Lynn Margulis, took Gaia to heart.
quote:NASA's Mars-bound Phoenix spacecraft is gearing up for a landmark landing near the martian north pole this month to find out whether the region could have once supported microbial life.
Phoenix is on course for a planned May 25 touchdown in the martian arctic that, if successful, will mark the first powered landing on Mars since NASA's hefty Viking 2 lander set down in 1976. But first, the probe is expected to fire its thrusters several times in the next few weeks to fine-tune its flight path.
"It's scary how smooth it's been," said Barry Goldstein, Phoenix project manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. "The vehicle has just been behaving beautifully."
The Phoenix lander tweaked its course in early April and is scheduled to fire its thrusters in three successive Saturday maneuvers beginning May 10. The spacecraft has flown so accurately that one of the maneuvers may not be necessary, Goldstein said.
Launched in August 2007, Phoenix is a stationary lander equipped with a trench-digging robotic arm to bite into the martian surface and scoop up samples of nearby soil and water ice. The probe's top-mounted suite of ovens and wet chemistry instruments are designed to help determine whether its arctic plain landing site - a region similar in latitude to central Greenland or northern Alaska on Earth - could have once proven habitable for primitive life.
"We're looking for all the ingredients for life," Phoenix deputy principle investigator Deborah Bass of JPL told SPACE.com.
Phoenix also includes a martian atmosphere-monitoring station designed to provide daily weather updates during the probe's planned three-month mission. Engineers at JPL will oversee the spacecraft's initial Mars descent and landing before transferring operations to a control center at the University of Arizona, Tucson, for the remainder of the $420 million mission.
"This is an area of Mars that I have spent my career studying and I cannot wait to see those first images," Bass said. "To see that ice, what that frozen tundra is going to look like...whatever we see will be amazing because no one's seen it before."
Unlike the most recent probes to land on Mars - NASA's twin rovers Spirit and Opportunity and the lost British lander Beagle 2 - Phoenix will not use airbags to cushion its arrival on the martian surface. Instead, it carries a set of rocket thrusters control its final descent, though its approach will mark the first powered landing attempt since NASA's Mars Polar Lander crashed near the planet's south pole in December 1999.
"I have always trumpeted the fact that we should be very guarded and very humble in our approach with what we're trying to do, because it is so difficult," Goldstein said, adding that engineers have identified and addressed as many of the risks as possible.
Phoenix's science team, led by principle investigator Peter Smith at the University of Arizona, Tucson, has been eagerly preparing for the lander's Mars arrival with a series of training simulations for landing day and mission operations. The most recent simulation, a dress rehearsal for Phoenix's entry and descent through the martian atmosphere, was scheduled for Tuesday.
"At this point, we feel we're in good shape and we want to do it. We're ready," Bass said. "This team is itching to get its hands on this stuff...it's show time."
*In de agenda zetquote:Op vrijdag 18 april 2008 18:33 schreef Quyxz_ het volgende:
Phoenix Lands on Mars in:
37 Days, 07 Hours and 03 Minuts on the 25th of may
Phoenix gaat samples uitgebreid onderzoeken. Hij gaat voornamelijk op zoek naar water of naar voormalig water, maar als er in zo een sample een microscopisch organisme zit, zal die natuurlijk ook wel worden ontdekt.quote:Op woensdag 7 mei 2008 08:10 schreef bigore het volgende:
gaat deze phoenix nou op zoek naar leven op mars?Microscopisch leven that is
Als ze er een budget voor hebben/krijgen....quote:Op woensdag 7 mei 2008 08:26 schreef NorthernStar het volgende:
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*In de agenda zet
Zonder het politiek te willen maken, als al het geld wat besteed is aan de oorlog in Irak nu eens in ruimtevaart was gestoken...
Anyhoe, onvoorstelbaar dat Spirit en Opportunity nog steeds, zij het met enkele kleine gebreken, functioneren. Petje af voor degene die dingen in elkaar hebben gezet.
Volgende stap zou een UAV moeten zijn imo.
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Het Landings gebied wordt netjes schoongemaaktquote:Op maandag 12 mei 2008 00:42 schreef ExperimentalFrentalMental het volgende:
Enorme stofhozen gezien op landingslocatie Phoenix
11-05-2008
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Beide stofhozen bevinden zich daarnaast exact op de geplande landingslocatie van de Phoenix Mars Lander, die op 25 mei zal landen in een ovaalvormig gebied dat Green Valley genoemd wordt....
Het ligt iig wel in de planning. De Phoenix lander is de eerste van een nieuwe lichting "Scout missions".quote:Op woensdag 7 mei 2008 23:12 schreef -CRASH- het volgende:
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Als ze er een budget voor hebben/krijgen....
Het vergt helaas wel nogal wat geduld.quote:NASA remains committed to creating additional "Scout" missions, such as the Phoenix lander, which would be selected from proposals submitted by members of the science community. Such missions might involve airborne vehicles, such as airplanes or balloons, or small landers that serve as investigation platforms. This approach could open up exciting new vistas by increasing the number of martian sites visited.
http://mars.jpl.nasa.gov/missions/future/futureMissions.htmlquote:The next Mars Scout is planned for launch in 2013.
voor een animatie hoe de missie van Phoenix op Mars gaat verlopen: http://news.bbc.co.uk/2/hi/science/nature/7408033.stmquote:Phoenix diary: Mission to Mars
On 25 May (GMT) Nasa's Phoenix lander will begin its descent to the northern plains of Mars. The robotic lab is due to investigate the region's climate and geology as well as determine whether it could support life.
Dr Tom Pike, from Imperial College London, is one of the scientists working on the mission. He will be writing a diary for the BBC News website in the run-up to the landing.
is dat live te volgen?quote:Op donderdag 22 mei 2008 12:56 schreef Quyxz_ het volgende:
Hij landt van de nacht van zondag op maandag om 1.38 's nachts.
Echt balen dat het zo laat is, want ik heb de volgende dag examen.
Dit staat bij schedule van NASA TVquote:Op donderdag 22 mei 2008 12:59 schreef Schunckelstar het volgende:
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is dat live te volgen?
op nasatv bijvoorbeeld?
En dan moet je zelf maar bekijken wat het precies isquote:May 25, Sunday
3 p.m. - Mars Phoenix Lander Briefing - JPL (Public and Media Channels)
6 p.m. - Mars Phoenix Lander Landing Coverage - JPL (Media Channel)
6:30 - 8:45 p.m. - Mars Phoenix Lander Landing Coverage - JPL (Public Channel)
9:30 p.m. - Mars Phoenix Lander Briefing - First Downlink of Data - JPL (Public and Media Channels)
May 26, Monday
6 - 10 a.m. - Mars Phoenix Lander Live Satellite Interviews - JPL (Media Channel)
12 a.m. - Mars Phoenix Lander Post Landing Briefing - JPL (Public and Media Channels)
2 p.m. - Mars Phoenix Lander Update Briefing - JPL (Public and Media Channels)
Plus 6 uur > Dat is 01:53 vannacht onze tijd.quote:NASA's Phoenix Mars Lander will reach Mars this evening with no further adjustments to its flight path. The first possible time for confirmation that Phoenix has landed will be at 7:53 p.m. Eastern Time today.
Ja ik zit ook te kijken... wel raar, bijna live vanaf een andere planeetquote:Op maandag 26 mei 2008 00:18 schreef star_gazer het volgende:
http://www.nasa.gov/multimedia/nasatv/index.html
Live coverage van de landing
Die film is echt zo leukquote:Op maandag 26 mei 2008 00:58 schreef LordNemephis het volgende:
eerst nog een uurtje animaties en uitleg-voor-dummies dus tijd voor reclame:
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Ja vanaf een paar uur terug is het allemaal automatisch. Toen werd er nog even gekeken of er een koerscorrectie nodig was maar dat hoefde niet.quote:Op maandag 26 mei 2008 01:28 schreef RemcoW85 het volgende:
http://www.nasa.gov/mission_pages/phoenix/main/
Moeten ze al die dingen op afstand doen of gebeurd dit allemaal automatisch? Ben hier nieuw in dusja, vandaar de vraag.
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