NASA's Wide-field Infrared Survey Explorer (WISE)
has discovered a pair of stars that has taken over the title for the
third-closest star system to the sun. The duo is the closest star system
discovered since 1916. Both stars in the new binary system are "brown
dwarfs," which are stars that are too small in mass to ever become hot
enough to ignite hydrogen fusion. As a result, they are very cool and
dim, resembling a giant planet like Jupiter more than a bright star like
the sun.
"The distance to this brown dwarf pair is 6.5 light-years -- so close
that Earth's television transmissions from 2006 are now arriving there,"
said Kevin Luhman, an associate professor of astronomy and astrophysics
at Penn State University,
University Park, Pa., and a researcher in Penn State's Center for
Exoplanets and Habitable Worlds. "It will be an excellent hunting ground
for planets because the system is very close to Earth, which makes it a
lot easier to see any planets orbiting either of the brown dwarfs."
Some of the world's leading astronomers -- including Great Britain's astronomer royal, Sir Martin Rees
-- believe advanced extraterrestrial civilizations, rather than using
different radio waves or visible light to signal, may be using an
entirely different communication medium such as ghostly neutrinos or
with gravitational waves (ripples in the fabric of space-time) or using
communication mechanisms we cannot begin to fathom.
“The
fact that we have not yet found the slightest evidence for life -- much
less intelligence -- beyond this Earth," said Arthur C. Clarke, "does
not surprise or disappoint me in the least. Our technology must still be
laughably primitive, we may be like jungle savages listening for the
throbbing of tom-toms while the ether around them carries more words per
second than they could utter in a lifetime."
Lord Rees, a leading cosmologist and astrophysicist who is the
president of Britain’s Royal Society and astronomer to the Queen of
England believes the existence of extraterrestrial life may be beyond
human understanding.
“They could be staring us in the face and we just don’t recognize
them. The problem is that we’re looking for something very much like us,
assuming that they at least have something like the same mathematics
and technology."
“I suspect there could be life and intelligence out there in forms we
can’t conceive. Just as a chimpanzee can’t understand quantum theory,
it could be there as aspects of reality that are beyond the capacity of
our brains.”
Frank Drake,
the founder of SETI and Drake's Equation, believes that satellite TV
and the “digital revolution” is making humanity invisible to aliens by
cutting the transmission of TV and radio signals into space. The earth
is currently surrounded by a 50 light year-wide “shell” of radiation
from analogue TV, radio and radar transmissions. According to Drake,
digital TV signals would look like white noise to a race of observing
aliens.
Although the signals have spread far enough to reach many nearby star
systems, they are rapidly vanishing in the wake of digital technology,
said Drake. In the 1960s, Drake spearheaded the conversion of the
Arecibo Observatory to a radio astronomy center. As a researcher, Drake
was involved in the early work on pulsars. Drake also designed the
Pioneer plaque with Carl Sagan in 1972, the first physical message sent
into space. The plaque was designed to be understandable by
extraterrestrials should they encounter it.
The newly discovered star system is named "WISE J104915.57-531906"
because it was discovered in an infrared map of the entire sky obtained
by WISE. It is only slightly farther away than the second-closest star, Barnard's star, which was discovered 6 light-years from the sun in 1916. The closest star system consists of: Alpha Centauri, found to be a neighbor of the sun in 1839 at 4.4 light-years away, and the fainter Proxima Centauri, discovered in 1917 at 4.2 light-years.
Edward (Ned) Wright, the principal investigator for the WISE satellite at UCLA,
said, "One major goal when proposing WISE was to find the closest stars
to the sun. WISE J1049-5319 is by far the closest star found to date
using the WISE data, and the close-up views of this binary system we can
get with big telescopes like Gemini and the future James Webb Space Telescope will tell us a lot about the low-mass stars known as brown dwarfs."
The results will be published in the Astrophysical Journal Letters. For more information go to http://www.nasa.gov/wise and http://wise.astro.ucla.edu and http://jpl.nasa.gov/wise.
Source: The Daily Galaxy via Penn State
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