The Digital Museum of Planetary Mapping is an online collection of maps of the planets and moons of our solar system. There are more than two thousand maps in the catalogue, some dating as far back as the 17th century, but the bulk of them, understandably, are much more recent; also understandably, Mars and the Moon are the subject of most of the maps (40 and 46 percent, respectively).
The site is more like a blog than a library catalogue: it’s powered by WordPress and the individual listings are blog posts, but that’s perfectly legitimate, albeit less elegant. (But then who am I to judge?)
The project was presented at the European Planetary Science Congress in Berlin last month: for news coverage, see Phys.org and Space.com; the press release is here. [WMS/WMS]
This huge star map tapestry is the work of Australian maker Sarah Spencer, who created it by hacking a 1980s-era knitting machine. Yes, this thing was knitted: it apparently took more than 100 hours and 15 kg (33 lbs) of (locally sourced Australian) wool to produce this 4.6×2.8-metre (15×9-foot) monster, which is accurate (with the caveat that an equatorial projection distorts familiar circumpolar constellations) and reasonably detailed: the constellations are labelled and the stars’ apparent magnitude is indicated. Space.com has the story. [Boing Boing]
Here’s a short video from the British Museum about a 13th-century celestial globe; it goes into the history of the globe, who made it, and how the stars appear on it (i.e. if the sky is represented as a globe, we’re on the inside: how do the stars appear on that globe?).
In 2016 I told you about Michael Plichta’s first globe, a delightfully retro hand-crafted globe of Mars based on Percival Lowell’s maps that showed the world covered in canals. Plichta’s second globe project is also cool and unusual, but in a completely different way: it’s a relief globe of the Moon. No globe gores were used to make this 30-cm globe: the textured surface is cast in artificial plaster and then painted by hand, a compulsively exacting process laid out in this short video:
Hand-crafted globes are never inexpensive, and though Michael never mentions prices, this one cannot be either. (I’ve seen his Mars globe listed for $1,850.) That said, this is a definite lust object. I desperately want one.
To create the maps, New Horizons researchers, led by Universities Space Research Association (USRA) senior staff scientist, Paul Schenk, at the Lunar and Planetary Institute, registered all the images from the Long Range Reconnaissance Imager (LORRI) and Multispectral Visible Imaging Camera (MVIC) systems together and assembled the mosaics. This labor-intensive effort required detailed alignment of surface features in overlapping images. Digital analysis of stereo images obtained by both cameras were used to create topographic maps for each region; these were then assembled into integrated topographic maps for each body. These new maps of Pluto and Charon were produced painstakingly over a two-year period as data were slowly transmitted to Earth from the New Horizons spacecraft. The quality of geographically and topographically accurate maps improved with each new batch of images that were returned to Earth.
One surprise revealed by the maps: both Pluto and Charon have a lot of elevation. For example: Pluto’s Tenzing Montes range (above) rises up to 6 km above the surrounding plain, and Charon has a topographic amplitude of 19 km (only Iapetus has more). That’s seriously craggy. Keep in mind that these are not large worlds: Pluto’s radius is 1,200 km, Charon’s 600 km. [Michele Bannister]
I knew that Europa, like Jupiter’s other major moons, was absolutely baked by radiation coming from Jupiter (Wikipedia reports it at 5.4 Sv/day, a lethal dose). It did not occur to me that that radiation was not evenly distributed. In preparation for future missions to Europa, a new study, using Galileo and Voyager data, tries to map where the radiation is most intense on the Europan surface, as well as how far that radiation penetrates beneath the surface. If there’s life on Europa, it’s probably where the radiation isn’t. [JPL]
Because of its thick and opaque atmosphere, Titan had to be mapped in radar and infrared during a series of close flybys by the Cassini spacecraft. One artifact of this process: the resolution, lighting and atmospheric conditions were not consistent, so mosaic images and maps of Titan’s surface showed visible seams. That’s been corrected in these infrared images of Titan’s surface, released last week. The false-colour images remap infrared wavelengths to the visible spectrum, using a band-ratio technique that minimizes seams. “With the seams now gone, this new collection of images is by far the best representation of how the globe of Titan might appear to the casual observer if it weren’t for the moon’s hazy atmosphere, and it likely will not be superseded for some time to come.”
The David Rumsey Map Collection has a number of virtual globes, but its AR Globe app may be the most unusual way to view them. Released last December for the iPhone and iPad, it uses augmented reality to superimpose one of seven celestial or terrestrial globes from the 15th through 19th centuries. The globes can be manipulated—spun, zoomed in and out—or observed from the inside (which is a good thing with celestial globes).
To be honest I’m not sold on using augmented reality to view virtual globes. It’s one thing to use AR to superimpose IKEA furniture in your living room: that makes sense, because it helps you visualize where the furniture would go and what it would look like. But it’s hard to see the utility of plunking a virtual globe in your living room: what’s the point of adding your surroundings as a backdrop? Case in point:
It’s neat but not particularly useful, is what I’m saying.
This is a map of the over one thousand stellar systems with known exoplanets. The map helps to visualize the relative distance and location of exoplanets systems with respect to Earth using a flattened polar projection (i.e. zero declination) with a logarithmic distance scale. Those systems with potentially habitable exoplanets are highlighted with a red circle. You will need to enlarge to see details (probably something good for a Prezi presentation). The map can be printed 27″ × 27″ @ 300dpi.
It’s an update to their original map from 2011. I imagine that there have been enough discoveries since 2014 that the map could be updated again.
The Moon and Mars were relatively early additions to Google Earth; that application may have been migrated to the web, but the planets and moons keep coming. Yesterday Google announced the addition of a dozen other worlds in our solar system; the space layer of Google Maps now includes planets Mercury, Venus and Mars; dwarf planets Ceres and Pluto;1 Jupiter’s moons Io, Europa and Ganymede; and Saturn’s moons Dione, Enceladus, Iapetus, Mimas, Rhea and Titan. Large moons Callisto and Triton aren’t included, and Iapetus is projected onto a sphere rather than appearing as the bizarre space walnut it is.
A new gravity map of Mars that shows the thickness of the Martian crust based on gravity measurements from Martian orbiters, reveals a crust that is less dense and shows less variation than earlier maps. “The researchers mapped the density of the Martian crust, estimating the average density is 2,582 kilograms per meter cubed (about 161 pounds per cubic foot). That’s comparable to the average density of the lunar crust. Typically, Mars’ crust has been considered at least as dense as Earth’s oceanic crust, which is about 2,900 kilograms per meter cubed (about 181 pounds per cubic foot).”