Interesting Maps

Gregor Samsa wrote: »

Olympus Mons is so big that if you were standing on the Martian surface, you wouldn't actually see it all. And if you were standing on the top of it, you wouldn't realise you were on such a high mountain. The gradient averages at only 5 degrees, and because Mars is small the horizon is only 3km away (at average human head height), so from any vantage point - on it or off it - you'd only be seeing a small part of the structure.

Looks like there are some steep cliffs along parts of its rim. Would be class to see up close.

Gaoth Laidir wrote: »

It would be, actually. On Mars you'd weigh only 38% of your Earth weight, so on Mars you could climb something 2.6 times higher for the same effort that you would expend on Earth.

I know, that's why i said it

KevRossi wrote: »

Hasn't this been the case for a good few years? Maybe National Geographic are just playing catch-up?

Yeah, that's the point of the article and the post (see the quote in it). NG are only getting around to recognising it now.

Interesting series of old maps and links here https://atlantic-cable.com/Maps/



First one, 1850's, the route survey bathymetry for the first transatlantic cable from Valentia to Newfoundland. Always been interested in these old charts, considering all the data was acquired under sail, lead line soundings, a sextant and a chronometer. The beginning of what would eventually become the internet.

The cable consisted of seven copper wires, each weighing 26 kg/km (107 pounds per nautical mile), covered with three coats of gutta-percha (as suggested by Jonathan Nash Hearder[16]), weighing 64 kg/km (261 pounds per nautical mile), and wound with tarred hemp, over which a sheath of 18 strands, each of seven iron wires, was laid in a close helix. It weighed nearly 550 kg/km (1.1 tons per nautical mile), was relatively flexible and was able to withstand a pull of several tens of kilonewtons (several tons).

The cable from the Gutta Percha Company was armoured separately by wire rope manufacturers, as was the usual practice at the time. In the rush to proceed, only four months were allowed for completion of the cable.[17] As no wire rope maker had the capacity to make so much cable on that timescale, the task was shared by two English firms – Glass, Elliot & Co., of Greenwich, and R.S. Newall and Company, of Birkenhead.[18] Late in manufacturing it was discovered that the respective sections had been made with strands twisted in opposite directions.[19] This meant that the two sections of cable could not be directly spliced wire-to-wire as the iron wire on both cables would unwind when it was put under tension during laying.[20] The problem was easily solved by splicing through an improvised wooden bracket to hold the wires in place,[21] but the mistake subsequently became magnified in the public mind.[19]

When did Chicago overtake NY in population? Or have I been under completely wrong impression my whole life?

Duckworth_Luas wrote: »

It hasn't.

What they're showing is not Chicago but what is referred to as Chicagoland, the entire urban conurbation that covers Chicago, its suburbs in Illinois and Northern Indiana.

Some of the people living in this area may never have set foot in Chicago proper in their lives.

If the same was were to be done for New York , ie; include Newark, New Jersey etc. it would be over 20 million.

Professor Moriarty wrote: »

The population density for Ireland is 186 people per square mile. The equivalent population area for New York has a population density of 13. You'd have better craic in Leitrim.

I’m not sure what you mean here.

The population density of New York City is 27,000 people per square mile. Even the entire state averages at 412. Maybe there’s some rural areas in the State with only 13 people in a square mile area, but it’s not indicative of the city, or state as a whole entity.

What do you mean by “equivalent population area”? An area in New York with the same population as Ireland? Or the population of an area of New York with the same size as Ireland?

retalivity wrote: »

Think the population density of the red area equivalent to the population of new york is 13

Ah, I understand now. Obviously haven’t fully woken up yet.

magicbastarder wrote: »

in the northern territories in canada, population density is 0.1 per sq mile.

There's a very good reason for that.