"There may be a giant ring of dark matter invisibly encircling the Earth,
increasing its mass and pulling much harder on orbiting satellites than
anything invisible should pull, according to preliminary research from a
scientist specializing the physics of GPS signaling and satellite
engineering. The dark-matter belt around the Earth could represent the
beginning of a radically new understanding of how dark matter works and
how it affects the human universe, or it could be something perfectly
valid but less exciting despite having been written up by New Scientist
and spreading to the rest of the geek universe on the basis of a single
oral presentation of preliminary research at a meeting of the American
Geophysical Union in December. The presentation came from telecom- and
GPS satellite expert Ben Harris, an assistant professor of mechanical
and aerospace engineering at the University of Texas- Arlington, who
based his conclusion on nine months' worth of data that could indicate
Earth's gravity was pulling harder on its ring of geostationary GPS
satellites than the accepted mass of the Earth would normally allow.
Since planets can't gain weight over the holidays like the rest of us,
Harris' conclusion was that something else was adding to the mass and
gravitational power of Earth – something that would have to be pretty
massive but almost completely undetectable, which would sound crazy if
predominant theories about the composition of the universe didn't assume
80 percent of it was made up of invisible dark matter. Harris
calculated that the increase in gravity could have come from dark
matter, but would have had to be an unexpectedly thick collection of it –
one ringing the earth in a band 120 miles thick and 45,000 miles wide.
Making elaborate claims in oral presentations, without nailing down all
the variables that could keep a set of results from being twisted into
something more interesting than the truth is a red flag for any
scientific presentation, let alone one making audacious claims about the
way dark matter behaves or weight of the Earth, according to an exasperated counterargument from Matthew R. Francis,
who earned a Ph.D. in physics and astronomy from Rutgers in 2005, held
visiting and assistant professorships at several Northeastern
universities and whose science writing has appeared in Ars Technica, The
New Yorker, Nautilus, BBC Future and others including his own science
blog at Galileo's Pendulum."
"In a cosmic coup, astronomers have found a celestial beacon known as a pulsar in orbit with not one, but two other stars.
The first-of-its-kind trio could soon be used to put Einstein's theory
of gravity, or general relativity, to an unprecedented test. 'It's a
wonderful laboratory that nature has given us,' says Paulo Freire, a
radio astronomer at the Max Planck Institute for Radio Astronomy in
Bonn, Germany, who was not involved in the work. 'It's almost made to
order.'"
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