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An online magazine says this about Kasardevi:

What makes the place what it is, is its positioning on the earth’s Van Allen Belt. Simply put, the region surrounding the Kasar Devi Temple has an enormous geomagnetic field, thanks to gaps in bands of radiation. As a result, Kasar Devi is endowed with a cosmic energy similar to that of UK’s Stonhenge and Peru’s Machu Pichu.

This is taken as a fact by many, even though a sign at the location itself is more indirect:

Kasardevi is [...] famous for being one of the three places on Earth under the influence of the Van Allen Belt [...], the other two places are Machu Pichu in Peru and Stonehenge in England [...].

Question: Does Kasardevi have something special related to the Van Allen Belt?

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    Just check the graphics at the NASA homepage Fun facts on Van Allen Belt and you will notice it has nothing to do with Kasardevi, nor UK or Peru. – bradbury9 Jan 22 at 8:02
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    @bradbury9The tweet by Alok Bhatt directly attributes the connection to NASA, but the sign doesn't actually seem to do that. The way I read it, it basically says: 'NASA says the van allen belt is X. We think that these three places are under the influence of it, and in our opinion that means Y'. The sign and outlook article are probably more notable than a tweet with <50 likes, so I think an answer here would need a bit more than NASAs fun facts page not mentioning Kasardevi. – tim Jan 22 at 10:18
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    MichaelK's answer is excellent in debunking this claim. However, just reading on to the next paragraph should be enough. It begins "Also known as Crank’s Ridge or the Hippie Hill, the area around the Kasar Devi Temple..." – CatchAsCatchCan Jan 23 at 3:33
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The claims are two wrong, one sort of correct

Before we start, it might be worth noting though that a strong magnetic field is more likely to keep radiation out than letting it in (*).

Anyway, the Earth's magnetic field at the surface, measured in nanotesla, and sourced from here. The image below has the locations in question marked with yellow stars (thank you Engineer Toast for the update).

enter image description here

Kasar Devi is at 29° 38′ 30.2″ N, 79° 39′ 42.4″ E, at which the field strength is between 48000 and 49000 nT. Respectable, but not remarkable, as the US and Canada, most of Australia, the upper half of Europe, and Russia and the other former Soviet states all exceed that. The map shows strengths between 22500 nT and 66500 nT (approx), meaning the median is at 44500 nT, hence this location has only slightly higher than median field strength.

So the claim that "the Kasar Devi Temple has an enormous geomagnetic field" is flat out wrong.

Stonehenge (51° 10′ 44″ N, 1° 49′ 34″ W) is in the same band, and the claim is therefore equally wrong about that.

Machu Picchu (13° 9′ 48″ S, 72° 32′ 44″ W) is near the South Atlantic Anomaly, just inside that thick 25000 nT line, and as such it has a remarkably low magnetic field strength, not a high one. It is that low intensity in the field that leads to the Van Allen Belt to coming closer to the surface of the Earth in that area.

It should be noted though that the South Atlantic Anomaly is huge. Since the year 2000 it has an area of over 100 million square kilometers.

enter image description here

The US by comparison, is only 10 million square kilometers. Russia clocks in at 17 million.

Machu Picchu is also only just on the edge of the SAA, not smack in the middle of it.

And — of course — on the ground we notice nothing of the Van Allen Belts since the atmosphere is a very effective shield against the particles in the belt.

So all in all, the quoted article has gotten several things confused...

  • The South Atlantic Anomaly is due to a weak geomagnetic field, not a strong one
  • Field strength determine the amount of radiation, not the other way around
  • A weakness in the field leads to more radiation, not the other way around
  • Stonehenge and Kasar Devi exist in areas of rather unremarkable geomagnetic field strength
  • The Van Allen Belts do not affect us on the surface of the planet

...unless of course the claims are about "energy" and "radiation" — in non-scientific meanings of the words — and not energy and radiation as talked about in science and astrophysics. If so, then all bets are off and nothing we talk about in scientific terms matters.

(*) On the latitudes in question. Near the poles — where the field lines intersect the surface of the Earth — the particles will spiral along the lines and come crashing down into the atmosphere, for plenty of ooh's and aah's of visiting tourists.

enter image description here

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    Might help to modify those images to place markers at Kasar Devi, Stonehenge, and Machu Picchu, just for easy reference. – Darrel Hoffman Jan 22 at 17:07
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    Surely when you said "sort of correct", you should have said "even more wrong"? – TonyK Jan 23 at 0:14
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    @TonyK The claim is "sort of correct" in that Machu Picchu is indeed in an area of the Earth where the magnetic field has an extreme value — at the low end of the scale — and that in space above it radiation is much more intense. – MichaelK Jan 23 at 14:26
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    Outstanding analysis. Do you happen to know whether/how that has changed over time? (I.e. can we also discount "Of course that's not true now, I was talking about 10,000 years ago!") – fectin Jan 23 at 15:16
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    It is not true that a strong magnetic field "keeps radiation out", in general -- the direction of the field is important. Charged particles are deflected by magnetic fields perpendicular to their route; magnetic fields "guide" particles onto a spiraling trajectory along their "field lines", This is why the solar wind is able to enter the atmosphere close to the poles where the magnetic field is strongest (as your diagram shows). It just has the "wrong" direction: Towards the ground, guiding, even funneling the particles towards the poles. – Peter - Reinstate Monica Jan 23 at 16:14

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