The latest Carnival of Space is stuffed with good things, among them Dave Mosher’s manipulations of an asteroid impact calculator run by Cardiff University’s Ed Gomez. Dave works through a worst-case scenario — a 1300-foot wide asteroid striking the East River, turning most of New York City into a crater. Fascinatingly, the impact calculator lets users adjust the parameters on such strikes, so that turning the impactor into a 400-meter piece of ice produces a crater 3.5 miles wide, two miles less than the first scenario. The calculator looks to be a great educational tool.
NextBigFuture continues to study the electric sail concept, developed at the Finnish Meteorological Institute and under active examination. Electric sails ride the solar wind, but unlike magsails, they use a mesh of tethers kept at high positive voltage, held in place by centrifugal acceleration from the spinning spacecraft. Solar wind protons, repelled by the positive voltage of the mesh, create the needed thrust, with accumulating electrons discharged periodically to keep the mesh voltage positive.
Because the voltage on each tether might be controlled independently, the electric field around the craft could be adjusted to deal with variable solar wind activity, at least in theory. NextBigFuture has details from the ESA electric sail workshop at the European Space Research and Technology Centre in May. A perfectly optimized electric sail, Brian believes, could reach speeds comparable to the solar wind maximum of 800 kilometers per second. This seems like quite a stretch, but we need space-based deployment of a prototype to test the basic principles.
Haumea is the latest dwarf planet to be added to the IAU list, studied this week by Astronomy at the CCSSC. Accompanied by twin moons, the oblong Kuiper Belt world formerly known as 2003 EL61 is fifty times the Earth-Sun distance and seems to have an icy crust over a rocky body, possibly the result of an impact that blew away earlier ices. Regrettably, another discovery controversy has dogged the story, with questions about whether this object was found by Mike Brown’s team at Caltech or a Spanish team that made an earlier announcement.
Says Astronomy at the CCSSC:
[T]here’s a bit of an ugly story that goes along with this one. Briefly, Dr. Brown’s team had been watching and observing this object, gathering data before they decided to announce or publish a discovery. Another team (from an observatory in Spain) made the announcement before Dr. Brown’s team did. However, it turns out that the Spanish team may have looked at web logs showing where Dr. Brown’s team was observing, and “discovered” the planet in Dr. Brown’s data rather than in their own observations. The IAU lists Dr. Brown’s team as the discoverers of Haumea’s moons, and adopted their suggested planetary name; however, they have not committed themselves by listing either team as the “discoverers” of Haumea itself.
The competition for first announcement can get downright unhealthy at times, as Haumea’s sordid story shows. This case verged unusually close to actual cheating, but even when it’s just a case of a race to the finish line, it can have repercussions. For example, a scientist may announce results in the media which never pan out in the long run, leading the public to distrust new scientific findings.
All too true. Read the post for more, but also check Mike Brown’s site for a full rundown. The larger and more gratifying issue is the presence of so many large Kuiper Belt objects, and the growing belief that we have many more such discoveries ahead of us. Could Earth-sized worlds be lurking in these dark outer regions? The Solar System proves to be so much more complex than it seemed just a few decades ago, a situation that is presumably true around other stars as well. What an exciting time as we develop the needed tools to identify and study these objects.