A new gravity map of Mars, based on data from three orbiting spacecraft, has been released. “Slight differences in Mars’ gravity changed the trajectory of the NASA spacecraft orbiting the planet, which altered the signal being sent from the spacecraft to the Deep Space Network. These small fluctuations in the orbital data were used to build a map of the Martian gravity field.”
The data enables the crustal thickness of Mars to be determined to a resolution of approximately 120 kilometres. Here’s a short video explaining the significance:
Another online map of Mars, this one titled (Is There) Life on Mars? and produced by Kenneth Field using ArcGIS. On the information pane he says, cryptically, “There’s a hidden element on the map that explains why I really made it. Happy hunting.” [via]
Point Google Maps or OpenStreetMap at a city like Dar es Salaam, Tanzania and you’ll get a reasonably good map. What you won’t get is Street View or street-level imagery—or, necessarily, the data that comes from a street-level understanding of the territory. NPR’s Nadia Whitehead looks at a joint project of the World Bank and Mapillary, a company that crowdsources street-level photos, to produce those images. “Volunteers are mounting camera rigs to their tuk tuks—three-wheeled motor-powered vehicles—to snap pictures as they cruise Dar es Salaam’s dirt roads. Others download the Mapillary app on their smartphones and capture images as they walk or hitch rides on motorbikes. In all, more than 260 people have volunteered.” [via]
The Electric Map of the Battle of Gettysburg, once a mainstay of Gettysburg National Military Park, closed in 2008; in 2012 it was purchased at auction for $14,000 by Scott Roland, a businessman who planned to reopen it as a tourist attraction in downtown Hanover, Pennsylvania, about 16 miles east of Gettysburg. Renovating and reassembling the map has taken Roland longer than he originally expected, the Evening Sun reports, but he believes the map will be ready by the end of the school year. [via]
A copy of an 1853 map of Texas by Jacob de Cordova found in a $10 box of ragtime sheet music sold at auction last weekend for $10,000. The map, once owned by surveyor James M. Manning, who died in 1872, was bought, along with a related letter, by Texas A&M University—Corpus Christi, whose library houses the Manning papers. [via]
The New York Times maps the impact of Russian airstrikes on the Syrian civil war. Using several maps to indicate the impact on each faction—government, rebels, ISIS and Kurds—strikes me as quite effective, as is the use of colour-highlighted text in the headings, rather than a legend, to indicate each faction.
In the 48 hours since I posted on how to support The Map Room, 18 readers have contributed a total of $166. That’s tremendous given the size of my audience: there may not be many of you, but you’re hardcore. The split between buying me a coffee (it’s a tip jar, actually) and contributing to my web hosting was 28:72. Contributions to the latter are sufficient to pay for 10 months of web hosting on my current plan; they’d take a big bite out of the additional cost of the upgraded plan, which I will now look into. I deeply appreciate the support. Thank you.
Jason-3 is the latest earth observation satellite tasked with measuring global sea surface height; its data will be used in weather and climate research (e.g., El Niño, climate change). Launched on January 17, it’s now in its six-month checkout phase and has produced its first complete map, which corresponds well with the map produced by the still-operational Jason-2 satellite, so that’s a good sign. [via]
Is Sexism a Problem in GIS? Caitlin Dempsey Morais of GIS Lounge grapples with a thorny subject. “Over a two week period in September of 2015, I opened a survey on GIS Lounge to those working in the geospatial industry in order to take a look at the question of, ‘is sexism in the workplace an issue for women (and men) working in GIS?’ This article reports back on the results from that survey.”