Using the highly sensitive radar telescope at the Cornell University-managed Arecibo Observatory in Puerto Rico and Goldstone antenna in California, Cornell astronomers have confirmed a theory that sunlight and the asteroid's shape determine how an asteroid's rotation evolves. Their research is reported today in Science Express, the online edition of the journal Science.
The Yarkovsky-O'Keefe-Radzievskii-Paddack Effect, named after a nineteenth century Russian civil engineer Ivan Yarkovsky, a late American planetary scientist John A. O'Keefe, a late Russian astronomer V.V. Radzievskii and NASA aerospace engineer Stephen J. Paddack, affectionately known as YORP, says that solar radiation will increase or decrease the rate of an asteroid's spin. This effect could help explain the formation of binary asteroids: The created centrifugal forces are so strong, that rubble-pile asteroids could break and form into two parts.
"For this particular asteroid, we confirmed that the expected strength of the YORP effect roughly matched the observed effect," says Jean-Luc Margot, Cornell assistant professor of astronomy.
Margot and Patrick A. Taylor, Cornell doctoral student in astronomy, are the lead authors of the research, "Spin Rate of Asteroid (54509) 2000 PH5 Increasing due to the YORP Effect." A companion paper, "Direct Detection of the Asteroidal YORP Effect," with research led by Stephen C. Lowry from Queen's University Belfast, United Kingdom, will be published concurrently in Science Express.
The astronomers examined asteroid 2000 PH5, which was discovered by MIT's Lincoln Laboratory's near-Earth asteroid search program (LINEAR) in August 2000.
The Arecibo Observatory takes high-resolution radar images, enabling the astronomers to construct digital shape models. With these models, the astronomers compared the predicted effect of YORP with the change in spin rate observed by Lowry's team. The theoretical calculations and the observed change in the spin rate agreed with each other, resulting in the first direct detection of YORP. And Arecibo's radar produces a more-detailed shape than data from an optical telescope, says Taylor.
Blaine Friedlander | EurekAlert!
Significantly more productivity in USP lasers
06.12.2016 | Fraunhofer-Institut für Lasertechnik ILT
Shape matters when light meets atom
05.12.2016 | Centre for Quantum Technologies at the National University of Singapore
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:...
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...
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...
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...
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,...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
07.12.2016 | Earth Sciences
07.12.2016 | Earth Sciences
07.12.2016 | Materials Sciences