Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Sprawling Mayan network discovered under Guatemala jungle

bbc.com

Post reply on HN
Print view View original

91–100 of 128 posts

Re: Sprawling Mayan network discovered under Guatemala jungle

#91

Post by Dangeranger »

mcbits wrote: post #86
Dangeranger wrote: post #49

Earlier quoted context omitted.

LiDAR collection is pretty dense from a data perspective. When I was working with helicopter collection teams we would regularly collect 1TB of point data per day at around 120 points per square meter. Based on the density of the canopy in Central America, the teams are probably using a density greater than that, and are using "multiple return" depth mapping so that they can see through the forest. Processing LiDAR d…

If my hasty math is in the ballpark, the raw data for 500 trillion square meters would be a few hundred petabytes. Not cheap, but cheap enough that I would guess the cost and logistics of acquiring the data are much more of an obstacle.

Yes that is true, logistical support and processing have considerable costs. For aerial LiDAR collection via helicopter you're looking at about $20,000 per day of onsite collection including the helicopter team, insurance, and support. That gets you high density low altitude assets, not including the processing and storage costs.

It's cheaper to fly with a fixed wing aircraft, but you will typically get lower density assets and the possibility of obscured imagery due to cloud coverage because of the higher collection altitude. However the advantage is you're able to cover a wider collection swath with each pass, and it's a lot easier to fly a fixed wing vs. helicopter so the pilots are cheaper.

Re: Sprawling Mayan network discovered under Guatemala jungle

#92

Post by arca_vorago »

vanderZwan wrote: post #27
danans wrote: post #6

Reminds me of the recent finding that the Amazon River basin was much more cultivated in the ancient past than was thought: https://www.theatlantic.com/science/archive/2017/03/its-now-...

Which in turn reminds me of Richard Feynman describing the Mayan Calendar in his famous lectures on quantum mechanics, as an example of how the Mayans understood how the planets moved by looking, that they even figured out a number of patterns and predictions, but that they still did not know why the planets moved as they did, his point being that current understanding of quantum mechanics is very similar to this[0].…

Once again someone many have accused of tinfoil battery being shown to be onto some nugget of truth. He had a medical scare recently, anyone know how he's doing?

Re: Sprawling Mayan network discovered under Guatemala jungle

#93

Post by patrickg_zill »

Dangeranger wrote: post #91
mcbits wrote: post #86

Earlier quoted context omitted.

If my hasty math is in the ballpark, the raw data for 500 trillion square meters would be a few hundred petabytes. Not cheap, but cheap enough that I would guess the cost and logistics of acquiring the data are much more of an obstacle.

Yes that is true, logistical support and processing have considerable costs. For aerial LiDAR collection via helicopter you're looking at about $20,000 per day of onsite collection including the helicopter team, insurance, and support. That gets you high density low altitude assets, not including the processing and storage costs. It's cheaper to fly with a fixed wing aircraft, but you will typically get lower density…

How much would the total weight be for the lidar equipment? I wonder if drones would be able to significantly reduce the price.

Re: Sprawling Mayan network discovered under Guatemala jungle

#94

Post by zo1 »

52-6F-62 wrote: post #29
wjnc wrote: post #16

Earlier quoted context omitted.

A few hints from the article: 810 sq miles mapped, a three year project and lidar flying by helicopter. Another giveaway is the search for MH370. In some dimensions Earth is still huge!

I guess I'll just have to study up on the tech. IIRC there was a fairly quick LIDAR demo put on by a team at MIT that scanned the campus and surrounding areas in a relatively brief amount of time using a drone, I think. My ignorance on the subject of LIDAR has me wondering why we can't use a faster traveling vehicle, or would it be possible to do perform scans with something like a fleet of balloons that stream the d…

LIDAR data requires precise location-information of the scanning-device, otherwise the data you collect is at best useless, and at-most wildly skewed. This is because all the points are in-reference to the location of the device. A faster traveling vehicle inherently means less-accurate location measurements.

Re: Sprawling Mayan network discovered under Guatemala jungle

#95

Post by jacobolus »

DrScump wrote: post #78
jacobolus wrote: post #44

Earlier quoted context omitted.

And the reason that there are only a few surviving books is that the Spanish conquerors plucked those out to send back to Europe as curios before they burned down all the libraries.

Most of the books themselves were destroyed as the work of heretics, e.g. https://en.wikipedia.org/wiki/Maya_codices

That’s exactly what I just said... the Spaniards burned all of the books except for a small handful which were sent back to Europe as curios.

> We found a large number of books in these characters and, as they contained nothing in which were not to be seen as superstition and lies of the devil, we burned them all, which they regretted to an amazing degree, and which caused them much affliction. – Bishop De Landa

Re: Sprawling Mayan network discovered under Guatemala jungle

#96

Post by jacobolus »

ajmurmann wrote: post #84
DrScump wrote: post #78

Earlier quoted context omitted.

Most of the books themselves were destroyed as the work of heretics, e.g. https://en.wikipedia.org/wiki/Maya_codices

This stuff drives me so nuts. It also seems to be something that I've only ever noticed being done by religious people who follow done monotheistic believe. Does anyone know if any destruction of a culture and its artifacts had happened by someone not motivated by monotheistic delusions?

Do you consider the Chinese cultural revolution to be the product of monotheistic delusion? What about the more recent Chinese occupation of Tibet?

What about the Nazi party? The Japanese occupiers of Korea and China during WWII?

The British burning the Burmese royal library in the late 19th century? Or the current massacres of Muslims in Myanmar by Buddhists?

The US Army in its genocide of indigenous North American tribes?

My impression is that there are at least some anti-intellectual authoritarians in every country, religion, and political movement.

Re: Sprawling Mayan network discovered under Guatemala jungle

#97

Post by bobsil1 »

patrickg_zill wrote: post #93
Dangeranger wrote: post #91

Earlier quoted context omitted.

Yes that is true, logistical support and processing have considerable costs. For aerial LiDAR collection via helicopter you're looking at about $20,000 per day of onsite collection including the helicopter team, insurance, and support. That gets you high density low altitude assets, not including the processing and storage costs. It's cheaper to fly with a fixed wing aircraft, but you will typically get lower density…

How much would the total weight be for the lidar equipment? I wonder if drones would be able to significantly reduce the price.

Met a Cal archeology ass’t prof doing this, quadcopter-mounted lidar.

Re: Sprawling Mayan network discovered under Guatemala jungle

#98

Post by zo1 »

ahakki wrote: post #83
Banthum wrote: post #75

Earlier quoted context omitted.

It should be noted - this definition as genocide as destruction of a culture (instead of physical murder of a people) also supports the idea of "white genocide": A targeted effort by people with power to liquidate white peoples' group identity ("abolish whiteness") and to marginalize and obscure their traditional cultural touchstones ("don't teach books by dead white men" and related efforts to avoid teaching Shakesp…

I just wanted to say that this is a pretty bad comment.

How about you instead engage with that individual if you disagree? I don't find his comment unwelcoming to discussion. Now, whether he is correct or wrong is entirely separate, but from my point of view all I'm seeing is discussion being shutdown in the name of feelings and prevailing opinion.

Re: Sprawling Mayan network discovered under Guatemala jungle

#99

Post by vanderZwan »

arca_vorago wrote: post #92
vanderZwan wrote: post #27

Earlier quoted context omitted.

Which in turn reminds me of Richard Feynman describing the Mayan Calendar in his famous lectures on quantum mechanics, as an example of how the Mayans understood how the planets moved by looking, that they even figured out a number of patterns and predictions, but that they still did not know why the planets moved as they did, his point being that current understanding of quantum mechanics is very similar to this[0].…

Once again someone many have accused of tinfoil battery being shown to be onto some nugget of truth. He had a medical scare recently, anyone know how he's doing?

I have trouble seeing the connection between your reply and my comment - did you intend to post it elsewhere and did it accidentally end up with mine?

EDIT: My best guess is that this was intended as a reply to https://news.ycombinator.com/item?id=16292738 an referring to Charles C Mann and his book?

Post reply on HN