Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

U-M scientist says Mars winds could pose challenges

31.07.2007
—but manageable ones—for NASA's Phoenix lander team

Martian winds probably won't cause serious problems for NASA's upcoming Phoenix Mars Lander mission but could complicate efforts to collect soil and ice at the landing site, according to University of Michigan atmospheric scientist Nilton Renno.

New results from U-M wind tunnel tests suggest that winds could blow away some of the laboriously collected soil and ice, but probably not enough to affect onboard laboratory experiments, said Renno, a member of the Phoenix science team.

"Basically, my conclusion is that if you do the delivery properly and plan it well, you can guarantee that a large fraction of the sample is going to fall inside the instrument intake," said Renno, an associate professor in the U-M College of Engineering's Department of Atmospheric, Oceanic and Space Sciences.

Set for launch from Florida as early as Aug. 3, the Phoenix spacecraft will land on the planet's northern arctic plains, analyzing soil and ice to see if it could support microbial life. An 8-foot robotic arm will scoop up the soil and dump it into onboard science instruments.

With funding from NASA, Renno and his graduate students have been studying the possibility that Martian winds could blow away bits of falling soil and ice as the samples are dropped.

Winds of up to 11 mph are expected much of the time at the Phoenix landing site during the three-month main mission, which begins with arrival on May 25, 2008. Renno calculated that if the soil samples were dropped from a height of 10 centimeters (4 inches)—as called for in the original mission plan—the vast majority of the particles wouldn't make it into the instrument intakes under windy conditions.

Based in part on Renno's work, the Phoenix team decided to move the Phoenix scoop closer to the science-instrument intakes before dropping the soil, he said.

Robert Bonitz, lead engineer on the robotic arm team at NASA's Jet Propulsion Laboratory in Pasadena, Calif., said the new plan is to dump the samples from 2 cm (0.8 inches). And Washington University in St. Louis researcher Raymond Arvidson, lead scientist on the robotic arm team, said the goal is to deliver samples to the instruments during calm periods.

"With Nilton's tests and Bob's ability to deliver at 2 cm., we should be OK," Arvidson said. "I am not particularly concerned about wind dispersal of our samples. Just another issue to keep in mind."

To test his wind-dispersal calculations, Renno and his graduate students completed about a dozen wind-tunnel experiments at his Ann Arbor laboratory in recent weeks. They placed a model of the Phoenix robotic-arm scoop inside the cylindrical, 10-foot-long test chamber.

The scoop contained wood grains of various densities to represent bits of martian dust, soil and ice. The grains were released from a height of 5 centimeters into simulated cross winds ranging from 1 to 10 meters per second (2.25 to 22.5 mph), and their trajectories were photographed with a high-speed camera.

Based on the wind-tunnel results, Renno concluded that only about one-third of the Phoenix samples would make it into the science-instrument intakes when dropped from 5 centimeters into winds of a few meters per second.

But losing two-thirds of a hard-won sample during a $420 million mission isn't as calamitous as it might sound, Renno said. The Phoenix instruments need about 1 gram per test, and the scoop will deliver several grams during each dump. So even if two-thirds of the sample blows away, there would be enough soil and ice to complete the test, he said.

And the recent decision to dump from a height of 2 centimeters, along with the plan to deliver samples during calm weather, should further reduce sample losses.

"We will deliver more volume than needed, in case of lateral transport," Arvidson said. "And we will deliver in calm conditions, based on examination of the meteorology data we collect."

Renno leads the Phoenix science team's atmospheric sciences theme group. His main research goal during the mission is to better understand the water cycle at the landing site. Mars is a frigid desert, and liquid water can't survive at the surface.

But subsurface ice exists in the Martian arctic. Some scientists suspect that near-surface ice periodically melts, during warmer parts of long-term climate cycles.

Since liquid water is required by all known forms of life, the melted ice could provide a home for hardy, opportunistic microorganisms. The Phoenix spacecraft is not equipped to detect current or past life, but it can determine if the prerequisites for life are present.

"The main goal of the mission is to see if there are conditions that could allow life to evolve on Mars, Renno said."Understanding the water cycle will help us answer that question."

Additional U-M tests concerning the dust cloud likely to be kicked up by the Phoenix landing engines have been delayed until September.

NASA's Phoenix mission is led by Peter Smith of the University of Arizona, with project management at the Jet Propulsion Laboratory and development partnership at Lockheed Martin, Denver. International contributions are provided by the Canadian Space Agency; the University of Neuchatel, Switzerland; the University of Copenhagen, Denmark; the Max Planck Institute, Germany; and the Finnish Meteorological Institute.

Jim Erickson | EurekAlert!
Further information:
http://www.umich.edu

More articles from Physics and Astronomy:

nachricht Significantly more productivity in USP lasers
06.12.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Shape matters when light meets atom
05.12.2016 | Centre for Quantum Technologies at the National University of Singapore

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Simple processing technique could cut cost of organic PV and wearable electronics

06.12.2016 | Materials Sciences

3-D printed kidney phantoms aid nuclear medicine dosing calibration

06.12.2016 | Medical Engineering

Robot on demand: Mobile machining of aircraft components with high precision

06.12.2016 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>