Author Topic: Mars Rover Curiosity  (Read 75684 times)

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #150 on: July 02, 2015, 09:44:08 AM »
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07.01.2015

NASA's Curiosity Mars Rover Studies Rock-Layer Contact Zone

As Mars emerges from passing nearly behind the sun, NASA has resumed full operations of the Curiosity rover, which has reached a site where at least two rock types meet.



NASA's Curiosity Mars rover is examining a valley where at least two types of bedrock meet, for clues about changes in ancient environmental conditions recorded by the rock.
In addition to two rock types for which this site was chosen, the rover has found a sandstone with grains of differing shapes and color.

Curiosity's international team has resumed full operations of the car-size mobile laboratory after a period of limited activity during most of June. The operations moratorium for Curiosity and other spacecraft at Mars happens about every 26 months, when Mars passes nearly behind the sun from Earth's perspective, and the sun interferes with radio communication between the two planets.

At the rover's current location near "Marias Pass" on Mount Sharp, Curiosity has found a zone where different types of bedrock neighbor each other. One is pale mudstone, like bedrock the mission examined previously at "Pahump Hills." Another is darker, finely bedded sandstone above the Pahrump-like mudstone. The rover team calls this sandstone the Stimson unit.

On Mars as on Earth, each layer of a sedimentary rock tells a story about the environment in which it was formed and modified. Contacts between adjacent layers hold particular interest as sites where changes in environmental conditions may be studied. Some contacts show smooth transitions; others are abrupt.

Curiosity climbed an incline of up to 21 degrees in late May to reach Marias Pass, guided by images from NASA's Mars Reconnaissance Orbiter showing Pahrump-like and Stimson outcrops close together.

"This site has exactly what we were looking for, and perhaps something extra," said Curiosity Project Scientist Ashwin Vasavada, of NASA's Jet Propulsion Laboratory, Pasadena, California. "Right at the contact between the Pahrump-like mudstone and the Stimson sandstone, there appears to be a thin band of coarser-grained rock that's different from either of them."

The in-between material is a sandstone that includes some larger grains, of mixed shapes and colors, compared to the overlying dark sandstone.
"The roundedness of some of the grains suggests they traveled long distances, but others are angular, perhaps meaning that they came from close by," Vasavada said. "Some grains are dark, others much lighter, which indicates that their composition varies. The grains are more diverse than in other sandstone we've examined with Curiosity."

The science team has identified rock targets for further close-up inspection of the textures and composition of the mudstone and sandstone exposed near Marias Pass. The team ancipates keeping Curiosity busy at this site for several weeks before driving higher on Mount Sharp.

Curiosity has been exploring on Mars since 2012. It reached the base of Mount Sharp last year after fruitfully investigating outcrops closer to its landing site and then trekking to the mountain. The main mission objective now is to examine successively higher layers of Mount Sharp.

JPL, a division of the California Institute of Technology in Pasadena, built the rover and manages the project for NASA's Science Mission Directorate in Washington. For more information about Curiosity, visit:

http://www.nasa.gov/msl
http://mars.nasa.gov/msl/

You can follow the mission on Facebook and Twitter at:

http://www.facebook.com/marscuriosity
http://www.twitter.com/marscuriosity
In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #151 on: July 02, 2015, 09:53:16 AM »








In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #152 on: July 09, 2015, 09:22:28 AM »

This view southeastward from Curiosity's Mast Camera (Mastcam) shows terrain judged difficult for traversing between the rover and an outcrop in the middle distance where a pale rock unit meets a darker rock unit above it. Credit: NASA/JPL-Caltech/MSSS

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NASA's Curiosity Mars rover climbed a hill Thursday to approach an alternative site for investigating a geological boundary, after a comparable site proved hard to reach.

The drive of about 72 feet (22 meters) up slopes as steep as 21 degrees brought Curiosity close to a target area where two distinctive types of bedrock meet. The rover science team wants to examine an outcrop that contains the contact between the pale rock unit the mission analyzed lower on Mount Sharp and a darker, bedded rock unit that the mission has not yet examined up close.

Two weeks ago, Curiosity was headed for a comparable geological contact farther south. Foiled by slippery slopes on the way there, the team rerouted the vehicle and chose a westward path. The mission's strategic planning keeps multiple route options open to deal with such situations.

"Mars can be very deceptive," said Chris Roumeliotis, Curiosity's lead rover driver at NASA's Jet Propulsion Laboratory, Pasadena, California. "We knew that polygonal sand ripples have caused Curiosity a lot of drive slip in the past, but there appeared to be terrain with rockier, more consolidated characteristics directly adjacent to these ripples. So we drove around the sand ripples onto what we expected to be firmer terrain that would give Curiosity better traction. Unfortunately, this terrain turned out to be unconsolidated material too, which definitely surprised us and Curiosity."

In three out of four drives between May 7 and May 13, Curiosity experienced wheel slippage in excess of the limit set for the drive, and it stopped mid-drive for safety. The rover's onboard software determines the amount of slippage occurring by comparing the wheel-rotation tally to actual drive distance calculated from analysis of images taken during the drive.

The rover was heading generally southward from near the base of a feature called "Jocko Butte" toward a geological contact in the eastern part of the "Logan Pass" area.

Routes to this contact site would have required driving across steeper slopes than Curiosity has yet experienced on Mars, and the rover had already experienced some sideways slipping on one slope in this area.

"We decided to go back to Jocko Butte, and, in parallel, work with the scientists to identify alternate routes," Roumeliotis said.

The team spent a few days analyzing images from the rover and from NASA's Mars Reconnaissance Orbiter to choose the best route for short-term and long-term objectives.

"One factor the science team considers is how much time to spend reaching a particular target, when there are many others ahead," said Curiosity Project Scientist Ashwin Vasavada of JPL. "We used observations from NASA's Mars Reconnaissance Orbiter to identify an alternative site for investigating the geological contact in the Logan Pass area. It's a little mind-blowing to drive up a hill to a site we saw only in satellite images and then find it in front of us."

Curiosity has been exploring on Mars since 2012. It reached the base of Mount Sharp last year after fruitfully investigating outcrops closer to its landing site and then trekking to the mountain. The main mission objective now is to examine successively higher layers of Mount Sharp.

JPL, a division of the California Institute of Technology in Pasadena, built the rover and manages the project for NASA's Science Mission Directorate in Washington. For more information about Curiosity, visit:

http://www.nasa.gov/msl
http://mars.nasa.gov/msl

You can follow the mission on Facebook and Twitter at:

http://www.facebook.com/marscuriosity
http://www.twitter.com/marscuriosity
In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #153 on: July 17, 2015, 09:00:33 AM »
Time for a wheel survey and evaluation.  NASA has already altered routes based on the conditions of the wheels.  As you can see they have been taking a beating... I hope they can last long enough to climb the mountain...









The complete wheel survey can be found here...

http://mars.nasa.gov/msl/multimedia/raw/?s=1046&camera=MAHLI
In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #154 on: August 04, 2015, 08:37:43 AM »
Three year anniversary... 8)

<a href="https://www.youtube.com/v/n4Dv7hJIv6Y" target="_blank" class="new_win">https://www.youtube.com/v/n4Dv7hJIv6Y</a>

In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #155 on: August 04, 2015, 08:46:10 AM »
In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #156 on: August 20, 2015, 09:10:48 AM »

Looking Up at Mars Rover Curiosity in 'Buckskin' Selfie

This low-angle self-portrait of NASA's Curiosity Mars rover shows the vehicle at the site from which it reached down to drill into a rock target called "Buckskin." The MAHLI camera on Curiosity's robotic arm took multiple images on Aug. 5, 2015, that were stitched together into this selfie. Credit: NASA/JPL-Caltech/MSSS

Quote
NASA's Curiosity Mars rover is driving toward the southwest after departing a region where for several weeks it investigated a geological contact zone and rocks that are unexpectedly high in silica and hydrogen content. The hydrogen indicates water bound to minerals in the ground.
In this "Marias Pass" region, Curiosity successfully used its drill to sample a rock target called "Buckskin" and then used the camera on its robotic arm for multiple images to be stitched into a self-portrait at the drilling site. The new Curiosity selfie from a dramatically low angle is online at:

http://mars.nasa.gov/multimedia/images/?ImageID=7438

The rover finished activities in Marias Pass on Aug. 12 and headed onward up Mount Sharp, the layered mountain it reached in September 2014. In drives on Aug. 12, 13, 14 and 18, it progressed 433 feet (132 meters), bringing Curiosity's total odometry since its August 2012 landing to 6.9 miles (11.1 kilometers).
Curiosity is carrying with it some of the sample powder drilled from Buckskin. The rover's internal laboratories are analyzing the material. The mission's science team members seek to understand why this area bears rocks with significantly higher levels of silica and hydrogen than other areas the rover has traversed.

Silica, monitored with Curiosity's laser-firing Chemistry and Camera (ChemCam) instrument, is a rock-forming chemical containing silicon and oxygen, commonly found on Earth as quartz. Hydrogen in the ground beneath the rover is monitored by the rover's Dynamic Albedo of Neutrons (DAN) instrument. It has been detected at low levels everywhere Curiosity has driven and is interpreted as the hydrogen in water molecules or hydroxyl ions bound within or absorbed onto minerals in the rocks and soil.

"The ground about 1 meter beneath the rover in this area holds three or four times as much water as the ground anywhere else Curiosity has driven during its three years on Mars," said DAN Principal Investigator Igor Mitrofanov of Space Research Institute, Moscow. DAN first detected the unexpectedly high level of hydrogen using its passive mode. Later, the rover drove back over the area using DAN in active mode, in which the instrument shoots neutrons into the ground and detects those that bounce off the subsurface, but preferentially interacting with hydrogen. The measurements confirmed hydrated material covered by a thin layer of drier material.

Curiosity initially noted the area with high silica and hydrogen on May 21 while climbing to a site where two types of sedimentary bedrock lie in contact with each other. Such contact zones can hold clues about ancient changes in environment, from conditions that produced the older rock type to conditions that produced the younger one. This contact is the lure that led the rover team to choose Marias Pass as a route toward higher layers of Mount Sharp. Pale mudstone, like bedrock the mission examined for the first several months after reaching Mount Sharp at an area called "Pahrump Hills," forms one side of the contact. The overlying side is darker, finely bedded sandstone.

Curiosity examined the Marias Pass contact zone closely with instruments mounted on its mast and arm. The unusual levels of silica and hydrogen in rocks passed during the climb prompted a choice to backtrack to examine that area and acquire a drilled sample.

Buckskin was the first rock drilled by Curiosity since an electrical circuit in the drill's percussion mechanism exhibited a small, transient short circuit in February during transfer of sample powder from the third target drilled in the Pahrump Hills area.

"We were pleased to see no repeat of the short circuit during the Buckskin drilling and sample transfer," said Steven Lee, deputy project manager for Curiosity at NASA's Jet Propulsion Laboratory, Pasadena, California. "It could come back, but we have made changes in fault protection to continue safely drilling even in the presence of small shorts. We also improved drill percuss circuit telemetry to gain more diagnostic information from any future occurrences."
Curiosity reached the base of Mount Sharp after two years of fruitfully investigating outcrops closer to its landing site and trekking to the mountain. The main mission objective now is to examine layers of lower Mount Sharp for ancient habitable environments and evidence about how early Mars environments evolved from wetter to drier conditions.

JPL, a division of the California Institute of Technology in Pasadena, built the rover and manages the project for NASA's Science Mission Directorate in Washington. For more information about Curiosity, visit:

http://www.nasa.gov/msl
http://mars.nasa.gov/msl/
In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #157 on: September 01, 2015, 09:38:56 AM »


Quote
Planning is no longer restricted, but we had to start at 6:00 PDT this morning to give the operations team enough time to uplink commands by the time the rover expects them.  Driving to work before sunrise reminded me of the sometimes odd times we had to wake up during the first 90 sols of the mission, when the entire operations team was on "Mars time."

 The team is very interested in the outcrop in front of the rover, so I had a very busy day as MAHLI/MARDI uplink lead today, even though we are planning just one sol.  We planned in advance for MAHLI nighttime imaging of CheMin's inlet and MAHLI's calibration target (using white and UV LEDs), so those activities were ready to go this morning.  But we had to prioritize and plan the details of observations of other contact science targets.  Because the Sol 1089 MAHLI images and APXS placement were not perfectly centered on the Buckskin dump pile, our top priority is to repeat those observations with updated positioning.  We planned MAHLI images of a target dubbed "Devon," which will also be measured by APXS.  Many of the targets of interest are difficult to reach with the arm, so the rover planners requested relatively low-resolution MAHLI images of them to support planning of more contact science on Sol 1092.  These targets were named "Pentagon," "Lebo," "Ivanhoe," and "Ledger," with Ledger being imaged in stereo by Mastcam because it is a candidate for brushing with the DRT.  Finally, the APXS will be placed on the dump pile for overnight integration.

We had to put more thought than usual into prioritizing various data for downlink, as we expect only 38 Mbits of data before Sol 1092 planning begins tomorrow morning.  This situation forced us to compress some of the MAHLI images more than usual, and to create new command sequences.  But if all goes well, we will receive enough data tomorrow morning to plan contact science on multiple targets.

by Ken Herkenhoff

In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #158 on: September 14, 2015, 09:05:01 AM »




In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #159 on: September 24, 2015, 01:11:46 PM »


In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

spuwho

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Re: Mars Rover Curiosity
« Reply #160 on: September 24, 2015, 01:18:33 PM »






To be honest, this part of Mars looks like Nevada between Winnemucca and Reno along I-80.

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #161 on: September 24, 2015, 02:41:39 PM »
Now that you mention it... there is a spot I lovingly refer to as hell... in Oman that looks like this too.  8)
In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #162 on: October 05, 2015, 09:16:01 AM »

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Mount Sharp Comes In Sharply
 
This composite image looking toward the higher regions of Mount Sharp was taken on September 9, 2015, by NASA's Curiosity rover. In the foreground -- about 2 miles (3 kilometers) from the rover -- is a long ridge teeming with hematite, an iron oxide. Just beyond is an undulating plain rich in clay minerals. And just beyond that are a multitude of rounded buttes, all high in sulfate minerals. The changing mineralogy in these layers of Mount Sharp suggests a changing environment in early Mars, though all involve exposure to water billions of years ago. The Curiosity team hopes to be able to explore these diverse areas in the months and years ahead. Further back in the image are striking, light-toned cliffs in rock that may have formed in drier times and now is heavily eroded by winds.
 

http://mars.jpl.nasa.gov/msl/news/whatsnew/index.cfm?FuseAction=ShowNews&NewsID=1860

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10.02.2015

Curiosity's Drill Hole and Location are Picture Perfect

On Tuesday, Sept. 29, NASA's Curiosity Mars rover drilled its eighth hole on Mars, and its fifth since reaching Mount Sharp one year ago. The drilling of the hole 2.6-inches (65 millimeters) deep in a rock the team labeled "Big Sky" is part of a multi-day, multi-step sequence that will result in the analysis of the Martian rock's ingredients in the rover's two onboard laboratories – the Chemistry and Mineralogy X-Ray diffractometer (CheMin) and the Sample Analysis at Mars (SAM) instrument suite.

"With Big Sky, we found the ordinary sandstone rock we were looking for," said Curiosity Project Scientist Ashwin Vasavada. "It also happens to be relatively near sandstone that looks as though it has been altered by fluids -- likely groundwater with other dissolved chemicals. We are hoping to drill that rock next, compare the results, and understand what changes have taken place."
The analyses of the Big Sky rock-powder samples by CheMin and SAM will occur over the next week. Meanwhile, the team will be turning the rover's attention and its wheels towards the second rock, where the sample analysis process will begin anew.

Curiosity is currently on the lower slopes of Mount Sharp in a region covered in sandstone called the Stimson Unit. Two weeks ago, still in the same general vicinity, Curiosity took a pair of long-range images toward higher regions of the mountain. In the foreground -- about 2 miles (3 kilometers) from the rover -- is a long ridge teeming with hematite, an iron oxide. Just beyond is an undulating plain rich in clay minerals. And just beyond that are a multitude of rounded buttes, all high in sulfate minerals. The changing mineralogy in these layers of Mount Sharp suggests a changing environment in early Mars, though all involve exposure to water billions of years ago. The Curiosity team hopes to be able to explore these diverse areas in the months and years ahead. Farther back in the image are striking, light-toned cliffs in rock that may have formed in drier times and now are heavily eroded by winds.

"The only thing more stunning than these images is the thought that Curiosity will be driving through those lower hills one day," Vasavada said. "We couldn't help but send a postcard back to all those following her journey."

NASA's Mars Science Laboratory Project is using Curiosity to assess ancient habitable environments and major changes in Martian environmental conditions. NASA's Jet Propulsion Laboratory, a division of Caltech, built the rover and manages the project for NASA's Science Mission Directorate in Washington.

For more information about Curiosity, visit http://www.nasa.gov/msl, and http://mars.nasa.gov/msl/. You can follow the mission on Facebook at http://www.facebook.com/marscuriosity and on Twitter at http://www.twitter.com/marscuriosity.
In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #163 on: October 14, 2015, 09:59:34 AM »
<a href="https://www.youtube.com/v/pwipxdQ74pU" target="_blank" class="new_win">https://www.youtube.com/v/pwipxdQ74pU</a>

In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."

BridgeTroll

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Re: Mars Rover Curiosity
« Reply #164 on: October 14, 2015, 10:02:44 AM »


Quote
10.13.2015
 
Curiosity Self-Portrait at 'Big Sky' Drilling Site
 
This self-portrait of NASA's Curiosity Mars rover shows the vehicle at the "Big Sky" site, where its drill collected the mission's fifth taste of Mount Sharp.

The scene combines dozens of images taken during the 1,126th Martian day, or sol, of Curiosity's work on Mars (Oct. 6, 2015, PDT), by the Mars Hand Lens Imager (MAHLI) camera at the end of the rover's robotic arm. The rock drilled at this site is sandstone in the Stimson geological unit inside Gale Crater. The location is on cross-bedded sandstone in which the cross bedding is more evident in views from when the rover was approaching the area, such as http://mars.nasa.gov/multimedia/images/?ImageID=7468.

The view is centered toward the west-northwest. It does not include the rover's robotic arm, though the shadow of the arm is visible on the ground. Wrist motions and turret rotations on the arm allowed MAHLI to acquire the mosaic's component images. The arm was positioned out of the shot in the images, or portions of images, that were used in this mosaic. This process was used previously in acquiring and assembling Curiosity self-portraits taken at sample-collection sites "Rocknest",  "John Klein" and "Windjana."

This portrait of the rover was designed to show the Chemistry and Camera (ChemCam) instrument atop the rover appearing level. This causes the horizon to appear to tilt toward the left, but in reality it is fairly flat.

For scale, the rover's wheels are 20 inches (50 centimeters) in diameter and about 16 inches (40 centimeters) wide. The drilled hole in the rock, appearing grey near the lower left corner of the image, is 0.63 inch (1.6 centimeters) in diameter.

MAHLI was built by Malin Space Science Systems, San Diego. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Science Laboratory Project for the NASA Science Mission Directorate, Washington. JPL designed and built the project's Curiosity rover.

More information about Curiosity is online at http://www.nasa.gov/msl and http://mars.nasa.gov/msl/.
 
In a boat at sea one of the men began to bore a hole in the bottom of the boat. On being remonstrating with, he answered, "I am only boring under my own seat." "Yes," said his companions, "but when the sea rushes in we shall all be drowned with you."