Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Engineering researcher seeks answers to asteroid deflection

29.05.2008
An Asteroid Deflection Research Center (ADRC) has been established on the Iowa State campus to bring researchers from around the world to develop asteroid deflection technologies. The center was signed into effect in April by the Office of the Executive Vice President and Provost.

“In the early 1990s, scientists around the world initiated studies to assess and devise methods to prevent near-Earth objects from striking Earth,” said Bong Wie, the Vance D. Coffman Chair Professor in Aerospace Engineering and director of the center. “However, it is now 2008, and there is no consensus on how to reliably deflect them in a timely manner,” he noted.

Wie, whose research expertise includes space vehicle dynamics and control, modeling and control of large space structures, and solar sail flight control system development and mission design, joined the Iowa State faculty last August. “I am very happy that Professor Bong Wie has joined the faculty at ISU,” said Elizabeth Hoffman, executive vice president and provost. “His work on asteroid deflection is exciting and of great importance.”

The ADRC will host an International Symposium on Asteroid Deflection Technology in fall 2008. Scientists and engineers from NASA, the European Space Agency, academia, and the aerospace industry will be invited to the Iowa State campus to formulate a roadmap for developing asteroid deflection technologies.

Despite the lack of an immediate threat from an asteroid strike, scientific evidence suggests the importance of researching preventive measures. Sixty-five million years ago, a six-mile-wide asteroid struck near the Yucatan Peninsula in Mexico and created the 106-mile-diameter Chicxulub Crater. Most scientists now believe that a global climate change caused by this asteroid impact may have led to the dinosaur extinction. Seventy-four million years ago, a smaller one-mile-wide asteroid struck in central Iowa, creating the Manson Crater. Now covered with soil, it is the largest crater in North America at more than 23 miles across.

Just 100 years ago, June 30, 1908, an asteroid or comet estimated at 100–200 feet in diameter exploded in the skies above Tunguska, Siberia. Known as the Tunguska Event, the explosion flattened trees and killed other vegetation over a 500,000-acre area. But if the explosion had occurred four hours later, it would have destroyed St. Petersburg or Moscow with an equivalent energy level of about 500 Hiroshima nuclear bombs.

The potential for such devastation has astronomers scanning the skies to find and track asteroids that pose a danger, and it has Wie initiating this concerted research effort now before any asteroids are discovered heading toward Earth.

Last November, NASA reported 900 known potentially hazardous objects (PHOs), most of which are asteroids. PHOs are defined as objects larger than 492 feet in diameter whose trajectories bring them to within about 4.6 million miles of the Earth’s orbit. NASA scientists estimate the total population of PHOs to be around 20,000. “However,” Wie said, “the asteroid we have to worry about is the asteroid that we don’t know.”

“Developing technologies that can be used to prevent or mitigate threats from asteroids while also advancing space exploration is a challenge we accept as we work to assure a high quality of life for future generations,” said Mark J. Kushner, dean of Iowa State’s College of Engineering. “This research center serves as an excellent opportunity to provide leadership on an issue that has worldwide implications.”

According to Tom Shih, professor and chair of aerospace engineering, “the potential for a major catastrophe created by an asteroid impacting Earth is very real. It is a matter of when, and humankind must be prepared for it. Our aerospace engineering department strongly supports Professor Bong Wie’s effort in establishing this center to address the engineering and science issues of asteroid deflection.”

Both high-energy nuclear explosions and low-energy non-nuclear alternatives will be studied as deflection techniques. The nuclear approach, which is often assessed to be 10–100 times more effective than non-nuclear approaches as stated in NASA’s 2007 report to Congress, will be researched to verify its effectiveness and determine its practical viability, according to Wie.

“A 20-meter (66 feet) standoff distance is often mentioned in the literature for a maximum velocity change of a 1-kilometer (0.6 mile) asteroid. However, we have to determine how close the nuclear explosion must be to effectively change the orbital trajectories of asteroids of different types, sizes, and shapes,” Wie explained. “We will develop high-fidelity physical models to reliably predict the velocity change and fragmentation caused by a nuclear standoff explosion.”

The non-nuclear alternatives include kinetic impactors and slow-pull gravity tractors. Wie, who has previously worked on solar sail technology as applied to asteroid deflection, will present his recent study, “Multiple gravity tractors in halo orbits for towing a target asteroid,” at the American Institute of Aeronautics and Astronautics Astrodynamics Specialists Conference in August. His paper has been accepted for publication in the AIAA Journal of Guidance, Control, and Dynamics.

The chances of having to use deflection technologies on an asteroid in the near future are admittedly remote. Scientists estimate the frequency of an extinction-class (6 miles in diameter or larger) object striking Earth as once every 50–100 million years, and for a 200-foot or larger object as once every 100–500 years.

The technologies that will be developed, including precision orbital guidance and navigation and control, however, have other applications as well. These may include future advanced space vehicles that will carry astronauts to an asteroid or Mars and homeland security applications.

Bong Wie | EurekAlert!
Further information:
http://www.iastate.edu

More articles from Physics and Astronomy:

nachricht A 100-year-old physics problem has been solved at EPFL
23.06.2017 | Ecole Polytechnique Fédérale de Lausanne

nachricht Quantum thermometer or optical refrigerator?
23.06.2017 | National Institute of Standards and Technology (NIST)

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>