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How the Moon Affects LHC Operations

Soulskill posted more than 2 years ago | from the werewolves-loose-at-cern dept.

Earth 64

New submitter NervousWreck writes "Physicists report that tidal conditions are affecting the hardware at the LHC. 'This effect has been known since the LEP days, the Large Electron Positron collider, the LHC predecessor. The LHC reuses the same circular tunnel as LEP. Twenty some years ago, it then came as a surprise that, given the 27 km circumference of the accelerator, the gravitational force exerted by the moon on one side is not the same as the one felt at the opposite side, creating a small distortion of the tunnel. Since the moon’s effect is very small, only large bodies like oceans feel its effect in the form of tides. But the LHC is such a sensitive apparatus, it can detect the minute deformations created by the small differences in the gravitational force across its diameter.'"

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Simple solution (3, Funny)

Anonymous Coward | more than 2 years ago | (#40263327)

BLOW UP THE MOON!

Re:Simple solution (1)

jd (1658) | more than 2 years ago | (#40263399)

Didn't Gerry and Sylvia Anderson do this in 1999?

Re:Simple solution (1)

BenSchuarmer (922752) | more than 2 years ago | (#40263625)

So Abian was right all along?

Re:Simple solution (1)

Iskender (1040286) | more than 2 years ago | (#40264369)

So Abian was right all along?

Plus points for old school. I only just managed to read this on my WebTV.

Re:Simple solution (2)

geogob (569250) | more than 2 years ago | (#40263645)

I thought it was what they were trying to do with their blackhole factory...

Re:Simple solution (0)

Anonymous Coward | more than 2 years ago | (#40264611)

No, they were trying to suck up the Earth. Completely different.

Re:Simple solution (1)

aynoknman (1071612) | more than 2 years ago | (#40264727)

If you think the moon is bad, see how a nearby black hole affects the LHC. If you think a nearby black hole is bad, see how a black hole caused by the LHC affects the LHC

Re:Simple solution (0)

Anonymous Coward | more than 2 years ago | (#40270977)

An old meme about this, http://www.imao.us/docs/NukeTheMoon.htm [www.imao.us] : )

how strange... (0)

magarity (164372) | more than 2 years ago | (#40263363)

How strange that so many humans can be so smart and do so many amazing things and yet so many others are so stupid in so many other ways.

Re:how strange... (3, Insightful)

Hatta (162192) | more than 2 years ago | (#40264593)

The crazy thing is that most of those incredibly smart people doing those amazing things are just as stupid as the rest of us in other ways.

Re:how strange... (0)

Anonymous Coward | more than 2 years ago | (#40266791)

Yeah but you're stupid in all ways.

Interesting (3, Interesting)

History's Coming To (1059484) | more than 2 years ago | (#40263367)

They also had problems with an intermittent "rogue signals" which later turned out to match the timetable of a nearby railway. I wonder whether it could, in theory at least, detect gravity waves?

Re:Interesting (3, Informative)

Anonymous Coward | more than 2 years ago | (#40263493)

They also had problems with an intermittent "rogue signals" which later turned out to match the timetable of a nearby railway. I wonder whether it could, in theory at least, detect gravity waves?

Not without much more sensitive equipment. Projects like LIGO that look for gravity waves have 4km long tunnels that they use for laser interferometry. That gives them much more sensitivity than the LHC can dream of having with it's setup and electronics.

Re:Interesting (2, Informative)

Anonymous Coward | more than 2 years ago | (#40266787)

The LHC is 27KM times the number of times an beam has to be accelerated.

Re:Interesting (0)

Anonymous Coward | more than 2 years ago | (#40267777)

Yes, projects like LIGO are much more sensitive than the LHC, but at least the LHC has discovered things.

LIGO hasn't discovered jack squat as of yet.

Re:Interesting (1)

Jeff DeMaagd (2015) | more than 2 years ago | (#40268941)

You're talking about very different devices though. LIGO is a considerably more specialized device than LHC, it's designed to do only one kind of experiment. Particle accelerators are more versatile.

That said, I'm not sure if LHC has actually discovered anything. They've taken data, and found interesting data but I don't think anyone's done complete analyses on that data to show an actual discovery.

Re:Interesting (1)

phrostie (121428) | more than 2 years ago | (#40264465)

or possibly passing asteroids.

Re:Interesting (1)

Anonymous Coward | more than 2 years ago | (#40266803)

That's what LIGO [wikipedia.org] and VIRGO [wikipedia.org] are trying to do. It turns out that it's actually extremely difficult to detect gravitational waves (the most promising sources being collisions between compact objects [wikipedia.org] ), and the sensitivities required are far, far beyond what the LHC could achieve. It essentially amounts to detecting a change in length of the detector arms of around 1 part in 10^21. That's like a 0.001mm change in the distance from Earth to the nearest star.

More or less the entire contingent of experimental physicists working in the LIGO-VIRGO Collaboration are dedicated to the problem of suppressing environmental and systematic noise sources, and some very sophisticated technologies have been developed to that end. And we still haven't detected any gravitational waves yet!

Re:Interesting (1)

Anonymous Coward | more than 2 years ago | (#40267161)

Surprised nobody has pointed this out
Eurofighter Typhoon and the Moon [aerosoft.com]

Re:Interesting (1)

EdIII (1114411) | more than 2 years ago | (#40278415)

That's a lot smarter than my first thought which was that it could be used as an early warning system for a Death Star coming into orbit and getting ready to fire.

Alderaan could have really used one of those. Although they were the first so it would be kinda hard to put the danger into the proper context.

After the first use, I would imagine the rest of the galaxy kept close tabs on where that fucker was. Probably messed with local economies the same way cops do on the roads. Death Star gets within a parsec of a star system and you see you vacation requests and sick days just skyrocket.

Well (1)

wideBlueSkies (618979) | more than 2 years ago | (#40263375)

Kind of a cool problem. I suppose that short of altering the moon's orbit, someone is going to have to build adjustments into the software... Would that even be possible? Such adjustments or approximations might invalidate results.

Oh the hell with it.... I'm tired of thinking logically today. I need a beer.

Re:Well (1)

jd (1658) | more than 2 years ago | (#40263433)

It might be better to run beams of known parameters and adjust the controlling magnets accordingly so that the beam is perfectly circular. The moon won't move enough between a calibration run and an actual run for the results to be invalid, and calibrating the magnets will be easier than calibrating the software.

Re:Well (1)

RightwingNutjob (1302813) | more than 2 years ago | (#40264443)

The moon won't move, but the earth will spin merrily along at 15 arcsec/sec and change the orientation of the ring relative to the moon.

Re:Well (1)

jd (1658) | more than 2 years ago | (#40265141)

If they can handle an uncalibrated ring and just wait for the moon to be in roughly the right place, then calibrating all the magnets before each run and enduring a change in tidal forces due to motion of 54,000 arcsecs (15 arcsecs/sec over the course of one hour) for any given one hour experiment will logically produce superior results to guesstimating.

Adding in a non-colliding ring whose sole purpose it is to provide continuous feedback for calibration purposes would logically improve results further.

My point is that you can ALWAYS take measurements to fix errors, and that fixes beforehand will ALWAYS produce cleaner, more repeatable results than adding in fixes after the fact, especially when you can't be sure of all the facts beforehand.

Re:Well (1)

kermidge (2221646) | more than 2 years ago | (#40266101)

I suggest that the issue, and the news of it, is not discovering gravity but rather the finding, delineating, understanding, and compensating for the effects of various celestial bodies and transient local phenomena - some of which might not have been totally obvious beforehand. This is new stuff, people, it's never been done before on anything like this scale, d'you think even your brighter fellow humans might not have considered _everything_ imaginable beforehand? Did you, all the years they were building it? Where were your comments and your wonderful insight before this 'news' was published?

Sorry, jd, that was in response to another post, but I'm lazy, half-drunk, and tired, so it's a lump.

I think your timing idea is interesting, wonder if it's been thought of and done - I don't follow CERN closely.

Running a calibration beam? Intriguing; yet how would one handle magnetic migration or collision, in other words, how to keep two beams separate within the same magnetic envelope? This issue, related ones, and more, seem to crop up repeatedly in various areas of fusion research and engineering from what I've read. There they're dealing with just one equivalent of beam or bottle. Um, bad memory, but wasn't this tried at Batavia? Or even back at LINEAC?

Your last part viz. "you can ALWAYS...", I ain't so sure of that. All I know is from wood: measure twice, cut once. I've no idea if'n it translates, or just how, to LHC.

Your sig reference is unknown to me; I'm still on walrus and carpenter. N'er mind, found it, thanks: lyrics alone worth the search.

Re:Well (0)

Anonymous Coward | more than 2 years ago | (#40266801)

Thanks guys, great work. Why don't you send the results of all your brainstorming over to the LHC guys. I'm sure that your bollocks will be invaluable to them, as I'm sure their top scientists must be baffled by this problem which you have managed to solve after a couple of minutes of thought.

Re:Well (1)

jd (1658) | more than 2 years ago | (#40266965)

It's unlikely but nonetheless possible that the LHC is running software I wrote when working for CERN. If so, they are suffering enough.

Re:Well (1)

kermidge (2221646) | more than 2 years ago | (#40267009)

Why you're replying to me I've no idea, 'cuz I figured nothing out. Perhaps a mis-placed "reply" choice. I found it fascinating that with all the gee-whiz boffinry going on the past twenty years that led to building and running the LHC that this bit viz. tides and lake levels and such didn't happen to occur to anyone. Seems to me it's one of those things that seem so damn obvious after the fact, but in real life happens when people do complex new stuff.

Re:Well (1)

jd (1658) | more than 2 years ago | (#40273011)

If you haven't seen their music-hall production of the album, it is PRECISELY what you'd expect from that lot.

Re:Well (3, Informative)

Zocalo (252965) | more than 2 years ago | (#40263977)

With hindsight, this probably shouldn't be a big surprise. There were some reports [bbc.co.uk] earlier this year about Loch Ness having a small but measurable tidal activity; something like 1.5mm across its 35km length. Given that the instruments at the LHC are apparently so finely tuned that they can track continental drift[1], it shouldn't really come as a major revelation that they can detect lunar tidal activity across the diameter of the LHC.

[1] Coincidentally, I found out about this as part of the whole issue over neutrinos supposedly travelling faster than light, which was finally given the official "no they don't" [web.cern.ch] by CERN today.

Re:Well (0)

Anonymous Coward | more than 2 years ago | (#40264037)

That's not tidal activity. That's Nessy!

Re:Well (1)

Isaac-1 (233099) | more than 2 years ago | (#40266751)

Am I the only one that is concerned that this came as a surprise? These people are supposed to have PhD's in Physics, and they don't think the big rock in the sky might have an effect on their toy?

Re:Well (2)

toruonu (1696670) | more than 2 years ago | (#40266775)

I think the "surprise" part was only to the ATLAS controller. The fact that tidal forces affect the beam has been known since LEP times as is the water level in lake Geneva and also the TGV schedule that used to have huge electricity spikes as they "grounded" their lines and said grounding happened to reach LHC 100m below causing the orbit of the beam to jump. Hell, I've been working in the CMS experiment since 2004 and I knew about the tidal force compensation need and that's why the LHC control room guy was calmly saying he has to adjust for moon's tide as it's part of their operating procedure. Same goes to monitoring the rain quantity and snow melting to knowing what the water level is in lake Geneva so that they can compensate for that too.

CERN, The Moon and The TGV Explained (0)

Anonymous Coward | more than 2 years ago | (#40268017)

Need to keep Peter away.. (1)

Brad1138 (590148) | more than 2 years ago | (#40263387)

Peter Griffin [youtube.com]

A different headline would be better... (5, Insightful)

tlambert (566799) | more than 2 years ago | (#40263401)

"LHC Experiment discovers gravity; Higgs Boson still missing, presumed dead."

-- Terry

Re:A different headline would be better... (0)

alexborges (313924) | more than 2 years ago | (#40263443)

Oh man. I want some modpoints... :)

LOL

Re:A different headline would be better... (0)

Anonymous Coward | more than 2 years ago | (#40264227)

Who the fuck is Terry and why are you quoting her?

Your mom (0)

Lord Lode (1290856) | more than 2 years ago | (#40263527)

Does the gravity field of your mom also affect this sensitive apparatus?

Re:Your mom (1)

drinkypoo (153816) | more than 2 years ago | (#40264979)

Your mom is so fat she has smaller fat women orbiting her.

Re:Your mom (1)

kyrsjo (2420192) | more than 2 years ago | (#40266653)

You know the mass of the orbiting bodys doesn't really matter, unless they are comparable in size?

Re:Your mom (1)

drinkypoo (153816) | more than 2 years ago | (#40267469)

You know the mass of the orbiting bodys doesn't really matter, unless they are comparable in size?

You know the plural of body is spelled with an I E S? Oh, I guess you don't.

You know that when you overanalyze a joke, you're putting the anal in asshole?

well.... (0)

Anonymous Coward | more than 2 years ago | (#40263979)

I guess the only option is to release the moon......

we've had a good run... but its time for you to move on!

Yes... Well... ummm (0)

Anonymous Coward | more than 2 years ago | (#40264261)

Do LHC operations affects the moon? lol

Re:Yes... Well... ummm (1)

bughunter (10093) | more than 2 years ago | (#40264283)

Yes, but our instruments are not yet sensitive enough to detect the effects.

Re:Yes... Well... ummm (0)

Anonymous Coward | more than 2 years ago | (#40266841)

The LHC isn't in Soviet Russia, so no reason to expect so.

Full Moon (5, Funny)

Anonymous Coward | more than 2 years ago | (#40264317)

I would guess that this is more of a problem when there's a full moon since the mass must be greater then.

Re:Full Moon (0)

Anonymous Coward | more than 2 years ago | (#40266197)

*checks Bad-Science-ometer* You broke it. Why did you do that?

Re:Full Moon (1)

Anonymous Coward | more than 2 years ago | (#40267983)

Actually, not only is this true, TFA says this is the case. The moon doesn't change mass, but a full moon implies the moon and sun are aligned, and therefore the tidal force is greater. This is the same effect that causes spring tides.

Re:Full Moon (0)

Anonymous Coward | more than 2 years ago | (#40267699)

When the moon is full, it reflects light using a quite large portion of its surface. Wouldn't this work the same way as a solar sail, thus giving the moon increased momentum, and thus increase its mass?

Re:Full Moon (0)

Anonymous Coward | more than 2 years ago | (#40267887)

Since when the Moon is full it is also further from the Sun than the Earth, if there is any effect from this it would be pushed into a larger orbit of the Earth thus slowing the Moon down, and you would get the opposite effect when the Moon is between the Earth and the Sun (i.e. when it is a new moon).

But I doubt any change in momentum from this effect would be even slightly significant, but IANAPhysicist.

The Quantum Diaries (3, Informative)

Spinalcold (955025) | more than 2 years ago | (#40264645)

The Quantum Diaries is one of my favorite blogs, it's updated by particle, nuclear and plasma scientists all over the world. They have a great range of topics too, not just about the data coming out of the LHC and the range of theories, but also the life of a scientists, how papers are published, covering conferences, heck even on the day in the life of cleaning a detector. It's a field I'm working to get into, so it's especially of interest to me but I recommend it to anyone interested in the world of high energy physics.

On a side note, there's a write up of what was talked about the the Neutrino Conference that happened last week. Even aside from faster than light travel, they are finding some very [quantumdiaries.org] weird [quantumdiaries.org] things [quantumdiaries.org]

This explains Texas supercollider project killed (-1)

Anonymous Coward | more than 2 years ago | (#40265509)

All those fat people wandering around would have wreaked havoc with the readings.

Protip to submitter... (1, Insightful)

bogie (31020) | more than 2 years ago | (#40265921)

Don't assume everyone knows what "LHC" stands for.

Re:Protip to submitter... (1)

Anonymous Coward | more than 2 years ago | (#40266759)

If you don't know the name and acronym of the greatest experiment of mankind to date, maybe you don't really belong on a site for nerds. Just saying.

Re:Protip to submitter... (1)

TeknoHog (164938) | more than 2 years ago | (#40267257)

It stands (pun intended) for Large Hardon Collider. It is the Real Men's (aka physicists') version of a cockfight.

gravety wave detector (0)

Anonymous Coward | more than 2 years ago | (#40265989)

so there is a gravety wave detector and if i were an advanced civilation i would communicate with gravity waves

Re:gravety wave detector (1)

Barryke (772876) | more than 2 years ago | (#40266889)

Doc this is 2012. You wasted another otherwise perfect timeline!
You where not supposed to disclose that until EUTC 21120103T23:04:31:0#.

mynewt deformation (0)

Anonymous Coward | more than 2 years ago | (#40266221)

But a newt is not a lizard

"only large bodies like oceans" (0)

Anonymous Coward | more than 2 years ago | (#40266633)

So what about the ground ?
If the moon pulls water toward it, it surely also affects the ground [wikipedia.org] .
And just as for water, latitude and longitude matters to tell the force received at a given time, so given a large enough object with good enough precision it can be (and has been) measured.

Am I missing something which makes this news ?

Disappointed... (1)

Eaglehawk (203548) | more than 2 years ago | (#40267547)

After reading the headline, I was looking forward to reading an article about LHC scientists have been transformed into werewolves...

Re:Disappointed... (0)

Anonymous Coward | more than 2 years ago | (#40268009)

...I was looking forward to reading an article about LHC scientists have been transformed into werewolves...

Shitty Dan Brown/Stephanie Meyers collab incoming!

A nit-picking point (0)

Anonymous Coward | more than 2 years ago | (#40268345)

The original post makes a vital error when they wrote "Since the moon’s effect is very small, only large bodies like oceans feel its effect in the form of tides." Actually everybody "feels" the effect of lunar tides. Where the ocean is different is that it can display the effect of gravity.

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