Similar to the recently discovered Higgs Boson, gravitational waves are very difficult to observe. They were first detected only in an indirect way, as ripples in the fabric of space-time by using radio signals from a pulsar-neutron star binary system. It now a team of researchers has been able to detect the “same effect at optical wavelengths, in the light from a pair of eclipsing white dwarf stars.”
“This result marks one of the cleanest and strongest detections of the effect of gravitational waves,” said team member Warren Brown of the Smithsonian Astrophysical Observatory (SAO).
“The team discovered the white dwarf pair last year. (White dwarfs are the remnant cores of stars like our Sun.) The system, called SDSS J065133.338+284423.37 (J0651 for short), contains two white dwarf stars so close together — one-third of the Earth-moon distance — that they make a complete orbit in less than 13 minutes.”
“Every six minutes the stars in J0651 eclipse each other as seen from Earth, which makes for an unparalleled and accurate clock some 3,000 light-years away,” said study lead author J.J. Hermes, a graduate student working with Professor Don Winget at The University of Texas at Austin.
“Einstein’s theory of general relativity predicts that moving objects create subtle ripples in the fabric of space-time, called gravitational waves. Gravitational waves should carry away energy, causing the stars to inch closer together and orbit each other faster and faster. The team was able to detect this effect in J0651.”
“Compared to April 2011, when we discovered this object, the eclipses now happen six seconds sooner than expected,” said team member Mukremin Kilic of The University of Oklahoma.
“This is a general relativistic effect you could measure with a wrist watch,” added SAO’s Warren Brown.
J0651 will provide an opportunity to compare future direct, space-based detection of gravitational waves with those inferred from the orbital decay, providing important benchmark tests of our understanding of the workings of gravity.
“The team expects that the period will shrink more and more each year, with eclipses happening more than 20 seconds sooner than otherwise expected by May 2013. The stars will eventually merge, in two million years. Future observations will continue to measure the orbital decay of this system, and attempt to understand how tides affect the merger of such stars.”
The new research will be published in The Astrophysical Journal Letters.
Source: Harvard-Smithsonian Center For Astrophysics
Image Credits: NASA
if they already eclips every six minutes and have lost 6 seconds in one year and are expected to lose 20 seconds this year with continued exponential decay of this rate who came up with 2 million years until merger? At this rate of closure they would only have a few years left. Anybody else with me here? 2011=6min 2012=5:54 2013=5:40 2014=4:50 2015=1:55 2016=already merged.
Brilliant deduction. Glad I often read comments to find additional info. Yours is outstanding by my quick re-calc. Now here’s a fun simple one for all. Tomorrow is 11 days till the 11th 9-11 date. Then on 9-12 it will be 101 days till 12-21 11:11am UTC. Some beauty in math like Euclid’s golden triangle & order from chaos in Mandelbrot sets. As actuarial tables show, The closer we get to any date the less chance there is for an accident or “event.” Do you think there might still be any validity to the Web-bot Timewave zero point? Our data only shows a current slight rise in volcanic related activity and .01 extra danger from limited nuclear exchange in Oct.