(Press-News.org) There are few places on Mars lower than this. On the left of this image, the floor of Melas Chasma sinks nine kilometres below the surrounding plains. New images from ESA's Mars Express highlight the complex history of this enormous martian canyon.
Melas Chasma is part of the huge Valles Marineris rift valley, which stretches for more than 4000 km across the surface of Mars. This image covers 200 x 100 km and covers an area of roughly 20 000 sq km, which is about the size of Slovenia. Around Melas Chasma, there is abundant evidence for water having flowed across Mars in the past. As well as ancient water-cut channels, there are lighter-coloured deposits of sulphate components that were probably deposited in a former lake.
The image was obtained on 1 July 2006 using the High-Resolution Stereo Camera (HRSC) on ESA's Mars Express spacecraft.
The valley sides show evidence of multiple large landslides that have created vast fan shapes of material. This debris appears rough and jumbled, contrasting with the underlying smoother surface visible further into the basin. The rocks display flow textures indicating that they were once deposited by liquid water, water ice or mud. Levees of sediment can also been seen here.
The colour-coded elevation map shows the large variations in altitude within this region. The difference from the floor, on the left of the image, to the plateau on the right is more than 9 km. But what do you measure elevations against on Mars? On Earth, we use sea level. For Mars, planetary scientists have derived an average shape and size for the planet based on spacecraft observations. They call this the 'areoid' and use its surface as the equivalent of sea level.
In the case of Melas Chasma, the deepest portions of the canyon are 5 km below the areoid, whilst the surrounding plateau rises to elevations of 4 km above.
On the high plateau at the top of the cliff, a few ancient valleys have been preserved. The orientation of the largest one is parallel to the edge of the cliff, which may indicate that the valley originally followed an old fault line. Remaining faults are probably the main reason for the instability of the flanks, which have frequently collapsed forming huge landslides.
INFORMATION:
Mars: How low can you go?
2010-10-10
[Attachments] See images for this press release:
ELSE PRESS RELEASES FROM THIS DATE:
HSAN 1: Identification of new mutations, more accurate diagnosis and improved genetic counseling
2010-10-10
Antwerp, Belgium – October 8, 2010– VIB researchers at the University of Antwerp have identified several mutations that play an important role in the development of Hereditary Sensory and Autonomous Neuropathy Type 1 (HSAN 1). HSAN 1 is a rare genetic disorder of the peripheral nervous system. Identification of the mutations will lead to a more accurate diagnosis of the disease in patients as well as improved genetic counseling and prenatal diagnostic tests for couples who are carriers and planning a pregnancy.
HSAN
Hereditary Sensory and Autonomous Neuropathy (HSAN) ...
Children's agitation after surgery may be preventable
2010-10-10
AUGUSTA, Ga. – Temporary combativeness after surgery—a complication affecting up to half of anesthetized children—may be preventable with drugs that decrease epinephrine production, according to a Medical College of Georgia pediatric anesthesiologist.
"Some children wake up after surgery and begin crying and become combative," said Dr. Ivan Florentino, associate professor of anesthesiology and perioperative medicine and pediatrics at MCG. "They are often extremely frightened, disoriented and refuse to be comforted, even after being reunited with their parents. Some even ...
Louisiana Tech researchers design, fabricate innovative energy harvesting device
2010-10-10
RUSTON, La. – Dr. Long Que, assistant professor of electrical engineering at Louisiana Tech University, has reported success in designing and fabricating a device that allows microscale electronic devices to harvest their own wasted energy.
The work was described in a paper published in the September edition of Applied Physics Letters and has also caught the attention of PhysOrg.com, a website that features breakthroughs in science and technology from all over the world.
The paper titled, "Light and thermal energy cell based on carbon nanotube films" and co-authored ...
Risks in multiple pregnancies
2010-10-10
The complication rate during pregnancy with twins is about 40%. Women with multiple pregnancies often develop pre-eclampsia, gestational diabetes, and hemorrhages during the term of their pregnancy. Joachim W Dudenhausen from the Charité Berlin University Medicine and Rolf F Maier from Magdeburg University Medical Center, investigate which risks can be minimized by close monitoring in multiple pregnancies (Dtsch Arztebl Int 2010; 107[38]: 663-8).
14 in 1000 pregnancies will be multiple pregnancies. The average term for multiple pregnancies is notably shorter (for twins, ...
Shift work and cancer
2010-10-10
Shift work can cause cancer. In the new issue of the Deutsches Ärzteblatt International (Dtsch Arztebl Int 2010; 107[38]: 657-62), Thomas C. Erren and colleagues describe the current state of knowledge in this area and point out the challenges lying ahead.
Although it is well known that short-term disturbances of circadian rhythms, such as jet lag, can impair a person's sense of well-being, researchers only recently began to ask whether chronic disruption of biological rhythms over the long term might promote cancer. The possibility of financial compensation in such cases ...
Got fish? Nutrition studies explore health benefits
2010-10-10
Some of America's most popular fish--salmon and albacore tuna, for example--are rich in healthful natural compounds known as omega-3 fatty acids. Ongoing studies by U.S. Department of Agriculture (USDA) chemist Darshan S. Kelley and co-investigators are helping uncover new details about how these fish-oil components help protect us from chronic diseases.
Kelley is with the USDA Agricultural Research Service (ARS) Western Human Nutrition Research Center at the University of California-Davis. ARS is the USDA's principal intramural scientific research agency.
In an early ...
Autistic children are not good at covering up their lies: Queen's University study
2010-10-10
Children with autism will tell white lies to protect other people's feelings and they are not very good at covering up their lies, according to a Queen's University study.
The study, conducted by psychology professor Beth Kelley and developmental psychology PhD student Annie Li, is one of the first scientific studies of lying and autism.
"The results are surprising because there is a notion that children with autism have difficulty appreciating the thoughts and feelings of other people, so we didn't expect them to lie to avoid saying things that may hurt others," says ...
Front-of-package symbols and systems: IOM phase 1 report
2010-10-10
Nutrition rating systems and their accompanying symbols are intended to help consumers make healthy choices, but shoppers may be confused by the variety of symbols that have proliferated in recent years. Moreover, different rating systems focus on different nutrients, and questions have been raised about the nutritional criteria underlying these systems. Front-of-Package Nutrition Rating Systems and Symbols: Phase 1 Report presents the preliminary findings of an Institute of Medicine committee's review of these nutrition information tools. and focuses on the criteria behind ...
Bloodstream infection surveillance inconsistent between institutions, U-M study shows
2010-10-10
The study, led by Matthew Niedner, M.D., assistant professor of Pediatrics and Communicable Diseases at U-M C.S. Mott Children's Hospital, was conducted by the National Association of Children's Hospitals and Related Institutions Pediatric Intensive Care Unit Focus Group. It appears in the October issue of the American Journal of Infection Control.
"There is an intense amount of attention being placed on measures of quality performance that have significant implications in pay-for-performance, and reimbursement," says Niedner, who led the study. "What you have is a desire ...
Targeted therapy promising for HER2-positive metastatic breast cancer
2010-10-10
A new type of breast cancer treatment has shown encouraging activity as a first-line therapy in HER2-positive metastatic disease, researchers reported at the 35th Congress of the European Society for Medical Oncology (ESMO) in Milan, Italy.
Principal investigator Edith Perez, MD, Mayo Clinic in Florida, presented the results of the first ever randomized trial of trastuzumab-DM1 (T-DM1) as a first-line treatment for metastatic breast cancer.
T-DM1 is the first of a new type of cancer medicine known as an antibody-drug conjugate. It binds together two existing cancer ...