Added 1 new A* page:The Hubble Space Telescope got a pretty good view of aurorae on the planet Uranus recently:|
image by NASA, ESA, and L. Lamy (Observatory of Paris, CNRS, CNES) (source)
Not exactly where you'd think they'd be (at poles perpendicular to the ring), are they? NASA's caption says:
|These are among the first clear images, taken from the distance of Earth, to show aurorae on the planet Uranus. Aurorae are produced when high-energy particles from the Sun cascade along magnetic field lines into a planet's upper atmosphere. This causes the planet's atmospheric gasses to fluoresce. The ultraviolet images were taken at the time of heightened solar activity in November 2011 that successively buffeted the Earth, Jupiter, and Uranus with a gusher of charged particles from the Sun. Because Uranus' magnetic field is inclined 59 degrees to its spin axis, the auroral spots appear far from the planet's north and south poles. This composite image combines 2011 Hubble observations of the aurorae in visible and ultraviolet light, 1986 Voyager 2 photos of the cyan disk of Uranus as seen in visible light, and 2011 Gemini Observatory observations of the faint ring system as seen in infrared light.|
Uranus' magnetic field is not only at a funny angle, it's also offset "from the center of the planet towards the south rotational pole by as much as one third of the planetary radius":
image by Ruslik0, per Voyager 2's 1986 readings (source)
Weird! Wikipedia says "Neptune has a similarly displaced and tilted magnetic field, suggesting that this may be a common feature of ice giants. One hypothesis is that, unlike the magnetic fields of the terrestrial and gas giant planets, which are generated within their cores, the ice giants' magnetic fields are generated by motion at relatively shallow depths, for instance, in the water–ammonia ocean."
I came across a webcomic with really nice art! It's called Astray3, and it's a sorta science-fiction fantasy adventure type of thing, I think. Anyway, in the last four or so pages, which were coming out about once a month (and then stopped entirely, but a recent blog post by the author says new developments are in store, so we can hope), the inking and coloring really reached an awesome level of gorgeousness, almost getting semi-abstract in parts if you look carefully, but always coming together into a perfectly intelligible image. NICE.
I'm still working away at A*'s upcoming subscription mode on the weekends; this past weekend I got the thingy done that will let subscribers change their password. WOO. Next I have to do a thingy to let them change their email address, oh and also a thing so you can reset your password if you've forgotten it--that one's kind of tricky because you have to send them an email with a special limited-use URL that resets it when clicked or something, I guess... Anyway yeah that's the kind of fun stuff I'm weekending on! And just to be clear, the comic will always be free--subscribers just get access to the extra-large comic size, and get the ads removed. Also one nice thing the real subscription mode will do that the current preview mode doesn't (that link in the lower right corner of the comics) is that as long as you don't log out or clear your browser's cookies, every time you come to the site it will come right up with your previously selected comic size, so if you've been reading in the HD-size, you'll see that right away when visiting the site, without having to click something to embiggen them.