Astrophysicists Use Apollo Seismic Array To Hunt For Gravitational Waves 25
KentuckyFC writes: Back in the 1970s, the astronauts from Apollos 12, 14, 15, and 16 set up an array of seismometers on the lunar surface to listen for moonquakes. This array sent back data until 1977, when NASA switched it off. Now astrophysicists are using this lunar seismic data in the hunt for gravitational waves. The idea is that gravitational waves must squeeze and stretch the Moon as they pass by and that at certain resonant frequencies, this could trigger the kind of seismic groans that the array ought to have picked up. However, the data shows no evidence of activity at the relevant frequencies.
That's important because it has allowed astronomers to put the strongest limits yet on the strength of gravitational waves in this part of the universe. Earlier this year, the same team used a similar approach with terrestrial seismic data to strengthen the existing limits by 9 orders of magnitude. The lunar data betters this by yet another order of magnitude because there is no noise from sources such as oceans, the atmosphere and plate tectonics. The work shows that good science on gravitational waves can be done without spending the hundreds of millions of dollars for bespoke gravitational wave detectors, such as LIGO, which have yet to find any evidence of the waves either.
That's important because it has allowed astronomers to put the strongest limits yet on the strength of gravitational waves in this part of the universe. Earlier this year, the same team used a similar approach with terrestrial seismic data to strengthen the existing limits by 9 orders of magnitude. The lunar data betters this by yet another order of magnitude because there is no noise from sources such as oceans, the atmosphere and plate tectonics. The work shows that good science on gravitational waves can be done without spending the hundreds of millions of dollars for bespoke gravitational wave detectors, such as LIGO, which have yet to find any evidence of the waves either.
Gravity Waves of Unusual Size? (Score:4, Funny)
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You mean the G. W. O. U. S's? You keep using that word. I do not think it means what you think it means.
Inconceivable.
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Mostly dead.
And so on.
Gratuitous LIGO Slam (Score:5, Insightful)
The work shows that good science on gravitational waves can be done without spending the hundreds of millions of dollars for bespoke gravitational wave detectors, such as LIGO, which have yet to find any evidence of the waves either.
Do you mean aside from the cost of putting seismometers on the moon in the first place?
The experiment referenced is a fabulously clever re-use of existing data, but it has nothing whatsoever to say about the funding case for LIGO. LIGO, like many cutting-edge experiments, requires very long-term technology development before it can produce a positive result. Some science requires long-term thinking, not just until the next quarter or the next election cycle.
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The experiment referenced is a fabulously clever re-use of existing data, but it has nothing whatsoever to say about the funding case for LIGO. LIGO, like many cutting-edge experiments, requires very long-term technology development before it can produce a positive result. Some science requires long-term thinking, not just until the next quarter or the next election cycle.
Indeed. One wonders what remarkable scientific discoveries and conclusions will result from creative analysis of today's data, forty years hence.
...At least, as long as we actually do continue to fund new instruments and research, and don't insist that all data collection is now 'done', and that all the work that remains is winnowing smaller and smaller pieces of useful information from the last century's scientific output.
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One of the challenges is that there is just so much data from modern experiments. E.g. the LHC throws a lot of irrelevant data away before it even hits the hard drives. To a layman like me it seems likely that some potentially useful data gets thrown away in this process.
You cannot fault the LHC designers for doing this; the data handling and storage there is awe-inducing. Transporting and storing orders of magnitude of (probably useless) more data is just not feasible.
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To a layman like me it seems likely that some potentially useful data gets thrown away in this process.
They keep a fraction of data randomly, with no filtering, in case their filtering algorithm has a bias or mistake that they missed. While ideally it would let them figure that out in the short run and change the filtering algorithm, in the long run the data is still there. Statistics won't be as great as if they kept all data, but it would still be something.
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"One wonders what remarkable scientific discoveries and conclusions will result from creative analysis of today's data, forty years hence."
None whatsoever if the data isn't curated.
One of my constant battles is to get resources to retain data from old space missions. They're flagwaving missions first and scientific expeditions second, which means there's very little interest in keeping record around for prolonged periods.
That's DESPITE pointing out that if the raw data for NOAA satellites hadn't been kept,
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have job security the rest of your life to hunt it down especially in this time of so many layoffs? That is what is wrong with science.
Which is why only one in ten of my classmates in physics grad school managed to keep a job in academia. Many left because they couldn't get a new job after their contract ran out, others quit when their project got canceled mid-stream (i.e. laid off). Yet more left when they stared a family, because they wanted more stability of income by going into industry work.
all the people here that have read something out of a school book that was originally printed more than 100 years ago
If you know of a textbook that covers general relativity from more than 100 years ago today, do tell considering it was mainly published about 9
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The seismographs were a piggy-back on what was essentially a political project.
Getting unexpected results like this out of data such as a seismograph simply means that any piece of hardware that lands on another planet, moon or comet will have what seismographic equipment put on board that the weight (and/ or data transmission) budget can support without busting anything else. Data links and relays would be additional ha
Lunar resonance can be quite sensitive. (Score:5, Insightful)
But only at specific resonant frequencies.
LIGO is in principle sensitive to very different frequencies of gravity waves.
Good science, me too! (Score:3)
My experiments with a laser pointer and a moldy old potato have clearly established that gravitational waves are not strong enough to affect it.
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Yes but have you tried the resonant frequencies?
This was attempted in the 1970s (Score:5, Informative)
The idea of using Lunar Seismic activilty to measure gravitational radiation dates back to the 1970s.
http://en.wikipedia.org/wiki/A... [wikipedia.org]
In particular, consider the purpose of the Lunar Surface Gravimeter (LSG).
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