Or as I like to call it, a Ceres circuit. Ba-dum-bum!
But Ceres-ly, folks…
This morning, at about 1239 GMT (or 7:39 AM where I am), the Dawn space probe successfully entered orbit around the dwarf planet Ceres. The NASA press release is here:
Unfortunately, Dawn is currently on the dark side of Ceres, and is orbiting slowly enough that it won’t come around to the light side until mid-April. So the best we get for a photo at the moment is this one from March 1:
This is historic as the first orbit of a dwarf planet (the New Horizons probe later this year will only fly by Pluto, I believe) and the first time a probe has orbited two different bodies. And it’s significant to me since it means Dawn has now visited both of the Main Belt protoplanets featured in Only Superhuman, first Vesta back in 2011 and now Ceres. With Vesta, the timing was right to let me incorporate a bit of what Dawn discovered into the novel during the revision process — but with Ceres I just have to hope nothing contradicts what I wrote. My main description of Ceres in the book was as follows:
The sunlit side of the dwarf planet was a dusty gray, except for the bright glints where craters or mining operations had exposed fresh ice beneath.
So far, so good, I’d say, given the other photo we got recently:
Scientists are speculating that those bright spots might be exposed ice, or maybe salt. Although you know what they kinda look like to me?
The on switch.
More news as it develops…
I’ve finally finished the copyedits to the manuscript for Only Superhuman. Actually I pretty much finished them yesterday, but since this is being handled the old-fashioned way — a hefty printout that I had to mark up by hand and will mail back to Tor tomorrow — I wanted to add all the changes to my digital file of the manuscript so there’s a backup record of them in case the pages get lost in the mail.
I’m a bit puzzled that this part of the process is being done old-school all the way, seeing as how my earlier editor-requested manuscript revisions were handled digitally. But I guess when you get to the copyediting phase, it’s deeper in the machinery of the publisher, or whatever, so I guess the procedure could be different. But it’s just been rather a long while since I’ve had to mark up pages and mail them back, rather than sending a Word file with changes tracked, or just sending my editor an e-mail listing the edits by page and line. When I’m sent physical pages, I still do take the red pen to them as a backup; but since it’s so rarely needed, I’ve let my notations get a little sloppy, so I’m a little out of practice on the proper format. I hope all my notations are clear.
But I was finally able to make a couple of fixes that I’ve been waiting to make for a while. One, which I’ve mentioned my intention to do before, was an update to a passage about the planetoid Vesta, incorporating some of the new information we’ve gained from the Dawn probe currently orbiting it. I replaced a conjectural passage about Vesta’s geology — something that Dawn has found no evidence to support as yet — with a mention of Rheasilvia Mons, the name of the enormous mountain in the center of Vesta’s south polar basin. At first I was going to say it was the tallest mountain in the Solar System, which it is as far as we know right now; but then I realized we could maybe discover a taller one somewhere out in the Kuiper Belt. So instead, considering the extent of human travel and colonization in the system at the time of the novel, I described it as the tallest mountain humans had ever climbed.
The other fix I’ve been waiting to make was to correct an oversight. In my last major revision of the novel before selling it, I reworked the backstory of a featured community in the novel so that they originated in a space habitat rather than on Earth. And a while back, after the previous set of post-sale revisions, I realized I’d accidentally left in a line in which a character from that community referred to his “Terran upbringing” and how it affected his perception of a certain situation. I was able to fix it by saying he’d resided on Earth for a time, which is a reasonable extrapolation from his backstory as it now stands.
Meanwhile, I’ve been consulting with my editors about a design issue. There’s an appendix in the book, a listing of the locations featured in the book and their relative positions within the Solar System, and I’ve never been happy with the format I used to present the information. I intended it merely as a stopgap and figured that if I ever sold the book, I’d consult with the editors/designers about coming up with something better. But I’d forgotten about that until just recently, doing the copyedits. But I had a little back-and-forth with Greg and Marco and came up with a couple of ideas, including a table format that I think works a lot better than what I had. So hopefully that will be all worked out, and I’m glad I remembered to ask about it while we’re still pretty early in the process of designing and assembling the book.
Anyway, with the copyedits done, Only Superhuman is now one step closer to being a completed book. All the major changes and adjustments are pretty much done by now; once we get to the galley proofs, with the typesetting and composition done, any further changes will probably be pretty minor. So the way the book is now is almost its final form, probably. Which means that any mistakes and plot holes I still haven’t caught are doomed to be immortalized (though with luck I’ll get a sequel and be able to rationalize or retcon them).
We finally got a news conference from the Dawn team reporting on their preliminary findings from the survey orbits of Vesta. Here’s a link to the video (I don’t seem to be able to embed it properly):
Summary of the findings that stood out to me:
- The huge impact basin that takes up most of the southern hemisphere of Vesta is actually two huge impact basins. The main one with the big mountain at the center, which is called Rheasilvia Basin, is overlapping another, slightly smaller and somewhat older impact basin. So Vesta’s southern hemisphere was struck by a huge impactor not just once, but on two separate occasions. The older basin and the mountain in Rheasilvia haven’t been named yet; the mountain is currently just called the “Central Complex” of Rheasilvia.
- The mysterious grooves that gird most of Vesta’s equatorial region are some kind of “ripples” resulting from the impacts. There are two sets of grooves, the main one that circles 2/3 of the planetoid, and an older set in the northern part of the other 1/3. The older set seems to be roughly centered on the older southern impact basin, and the younger equatorial ridges roughly center on Rheasilvia.
- There’s a wide variety of different materials visible on the surface, suggesting a complex geologic history, but no hard evidence yet that Vesta’s mantle is exposed in the impact basins. However, it could be buried under looser regolith (i.e. “soil”). But the geologists are excited at how well Vesta’s surface has retained a record of its complicated history.
So how does this affect what I wrote about Vesta in Only Superhuman? Well, I didn’t really say that much about the planetoid itself, but there is one sentence in Chapter 4 that I’ll definitely have to reword in copyedits, a description of the southern polar “crater” that’s no longer accurate. Hopefully they’ll at least coin a name for the big mountain before the text gets locked down.
What’s surprising to me is how little attention the Vesta mission is getting in the news. It’s been hours since the press conference ended, and it’s very hard to find coverage of it, even on the science news sites. And at the conference itself, even though it went out live over the Internet, there were only a few questions and a lot of dead air during the Q&A period. I mean, this is exciting stuff! Vesta is one of the weirdest, coolest worlds we’ve seen, with all sorts of fascinating features.
The latest news from the Dawn probe at Vesta: NASA has posted a video showing a full rotation of the protoplanet, compiled from Dawn photographs. I don’t seem to be able to get the embed code to work, so here’s a link:
It’s fascinating to watch, with so many complex features. I’m really wondering what caused those parallel striations around the equator. I’m also wondering if that big mountain in the southern hemisphere is really what scientists have assumed it was, the central bulge of a crater so big it pretty much flattened out the rest of the hemisphere. It doesn’t really look like there’s a crater there. Maybe it’s so old that the edges have been worn away, but maybe the mountain is something else. And that would mean I’d have to do a bit of rewriting in Only Superhuman.
Yesterday, July 16, 2011, NASA’s Dawn space probe entered orbit around the asteroid (or more properly, protoplanet) Vesta, the second-most massive object in the Main Asteroid Belt. This is a mission I’ve following with interest, and I made a previous post about it back in April. But now I can reveal why I’m particularly interested in this mission — because my upcoming novel Only Superhuman is set in the Asteroid Belt, and much of its action takes place on habitats around Vesta (or around Ceres, which Dawn will visit in 2015). The novel mentions little enough about Vesta itself that I hope I won’t have to do any rewrites as a result of Dawn‘s findings, but I’m going to keep my eye on this just in case, and who knows — maybe I’ll get to write more about Vesta in a sequel.
Here’s the NASA press release:
And here’s the clearest photo of Vesta to date, taken on July 9:
Today I was catching up on the status of the Dawn space probe, which is mere months away from a rendezvous with Vesta, one of the largest asteroids in the Main Asteroid Belt, so much so that the Dawn mission scientists prefer to call it a protoplanet. Dawn is a really cool mission, an ion-powered spacecraft maneuverable enough to rendezvous with Vesta, spend a year in orbit of it, then thrust its way to a rendezvous with Ceres, the full-on dwarf planet member of the Main Belt, in 2015. We’ll finally get detailed images and surveys of these sub-planetary bodies, which are very different from each other: Vesta is dry and rocky and differentiated like a planet, Ceres carbonaceous and probably covered in a thick layer of ice that contains more fresh water than exists on Earth. These are of particular interest to me because of the spec novel I’ve written that’s set in the asteroid belt, and which I’ve alluded to before on this blog.
Anyway, another article I looked at today was this one from the JPL Dawn journal page, and I noted the following paragraph in it:
In December, we saw that by sensing the irregularities in the gravity field, Dawn will reveal the nature of Vesta’s internal structure. Until those detailed measurements have been made and accounted for in the design of the flight plan, however, the subtle effects of the gravity field will cause deviations from the planned trajectory. Therefore, as the spacecraft travels from one science orbit to another, it will thrust for a few days and then stop to allow navigators to get a new fix on its position. As it points its main antenna to Earth, the Doppler shift of its radio signal will reveal its speed, and the time for radio signals (traveling, as all readers know so well, at the universal limit of the speed of light) to make the round trip will yield its distance. Combining those results with other data, mission controllers will update the plan for where to point the thruster at each instant during the next phase of the spiral travel, check it, double check it, and transmit it to the distant explorer which will put it into action. This intensive process will be repeated every few days as Dawn maneuvers between science orbits.
I think that “science orbit” is the most awesome phrase I’ve seen all week. Everything is made cooler by putting “science” in front of it. Can’t you just hear it? “Helmsman! Prepare to enter… science orbit!”
Dawn will enter science orbit! of Vesta in the science month of Science July, and will surely do much science to it.