French, a doctoral candidate in aerospace engineering at North Carolina State University, has determined a way to effectively divert asteroids and other threatening objects from impacting Earth by attaching a long tether and ballast to the incoming object. By attaching the ballast, French explains, "you change the object's center of mass, effectively changing the object's orbit and allowing it to pass by the Earth, rather than impacting it."
Sound far-fetched? NASA's Near Earth Object Program has identified more than 1,000 "potentially hazardous asteroids" and they are finding more all the time. "While none of these objects is currently projected to hit Earth in the near future, slight changes in the orbits of these bodies, which could be caused by the gravitational pull of other objects, push from the solar wind, or some other effect could cause an intersection," French explains.
So French, and NC State Associate Professor of Mechanical and Aerospace Engineering Andre Mazzoleni, studied whether an asteroid-tether-ballast system could effectively alter the motion of an asteroid to ensure it missed hitting Earth. The answer? Yes.
"It's hard to imagine the scale of both the problem and the potential solutions," French says. "The Earth has been hit by objects from space many times before, so we know how bad the effects could be. For example, about 65 million years ago, a very large asteroid is thought to have hit the Earth in the southern Gulf of Mexico, wiping out the dinosaurs, and, in 1907, a very small airburst of a comet over Siberia flattened a forest over an area equal in size to New York City. The scale of our solution is similarly hard to imagine.
"Using a tether somewhere between 1,000 kilometers (roughly the distance from Raleigh to Miami) to 100,000 kilometers (you could wrap this around the Earth two and a half times) to divert an asteroid sounds extreme. But compare it to other schemes," French says, "They are all pretty far out. Other schemes include: a call for painting the asteroids in order to alter how light may influence their orbit; a plan that would guide a second asteroid into the threatening one; and of course, there are nukes. Nuclear weapons are an intriguing possibility, but have considerable political and technical obstacles. Would the rest of the world trust us to nuke an asteroid? Would we trust anyone else? And would the asteroid break into multiple asteroids, giving us more problems to solve?"
The research was first presented last month at the NC State Graduate Student Research Symposium in Raleigh, N.C. The research, "Trajectory Diversion of an Earth-Threatening Asteroid via Elastic, Massive Tether-Ballast System," has also been reviewed and accepted for presentation this September at the American Institute of Aeronautics and Astronautics SPACE 2009 Conference and Exposition in Pasadena, CA.
Matt Shipman | EurekAlert!
Structured light and nanomaterials open new ways to tailor light at the nanoscale
23.04.2018 | Academy of Finland
On the shape of the 'petal' for the dissipation curve
23.04.2018 | Lobachevsky University
Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.
Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
23.04.2018 | Physics and Astronomy
23.04.2018 | Physics and Astronomy
23.04.2018 | Trade Fair News