The Random Walk
Saturday, July 24, 2004
  Aurora Borealis

Finally.

Returning from the Lakes 10 multiplex, after Nick, Jere and I had watched the CGI sparkle of Spiderman 2, Jere noticed a glowing curtain of starstuff hanging over the northern horizon. We drove out of town, past the street lights, into the fields and turned into a closed side road, as the curtain split into two, three, four sheets...

The sky flickered and throbbed silently - waves of grey light chasing one another through ghostly ducts carved into the sky, seeking heaven. Countless thin sinuous channels of darkness veined the dancing plasma in the zenith, imperceptibly shifting as the storm's front lines moved through the thermosphere. A black gulf beneath the great northern curtain was suddenly filled with a succession of new sheets blazing into life. Every so often, a filament, a fold of these new curtains would erupt brilliantly, and like a flame on a fuse, travel down the length of the delicate film.

Colours began to emerge. Oxide blue-greens, trimmed with nitric pinks and purples. The curtains to the north faded, but the pulsing rays above speared more intently into space. The battle between Sunspot 652 and the churning iron below had found a new focus.

Five days before leaving Duluth, I was getting my send-off.

It was cold. We pulled ourselves away from the erie half-darkness and returned to civilization's smothering half-lights.




Duncan Young @ 10:51:00 PM | Post a Comment (3 have been added)
Friday, July 23, 2004
  Iapetus - giant crater still there...


Cassini's ISS system records images with a depth of 12-bits (4096 gray shades) as opposed to the personal computing standard of 8-bits (256 gray shades) in any given channel. Since the human eye can at best resolve between 16 and 20 gray shades, 8-bits is fine for the web; however, the extra depth provided by 12-bits may prove invaluble for science. However, this means that the quickie raw images put on the web will be clipped by the automatic 12 to 8-bit transistion. Only after careful reconstruction by the folks at CICLOPS do we get the full picture.
Earlier this month, I observed that Cassini appeared to have picked up a large crater in the mysterious Cassini Regio, a region covered with reddish-black material that covers the moon Iapetus' leading side. CICLOPS has rescently released a reprocessed image of Iapetus. The large crater appears to be still there - the shaded eastern scarp is visible at the edge of the regio, and there are hints of an illuminated western edge and a central peak. Now visible is the odd circular feature Voyager 1 observed at the eastern end of Cassini Regio, as well as an unnamed medium-sized crater barely detected in Voyager imagery to the south of Cassini Regio.
Andrew Gray suggested on this USENET thread that the big crater in Cassini Regio might be Roland, a 144-km wide basin seen in Voyager 2 coverage of Iapetus' north pole. The thing I am seeing is on the order of 400-km wide, and further south.
I am less certain of the gravitaion capture of the ejecta senaraio I laid out in the earlier post - it may be that I had it backward.

Duncan Young @ 2:00:00 PM | Post a Comment (0 have been added)
Tuesday, July 20, 2004
  35 years since the night that (unfortunately) changed very little...

The U. S. House Appropriations Committee choose the low-key 35th anniversary of the landing of the Eagle to eliminate the new Vision for Space Exploration from the VA-HUD budget. Projects Constellation (which would build the new Crew Exploration Vehicle) and Promthemus (responsible for the Jupiter Icy Moons Orbiter) are effectively nixed unless the Senate comes riding to the rescue. And in this election year, it is hard to see anyone defending the Shuttle-Killer or a flying nuclear-reactor, especially in this age of Yucca.

UPDATE:The star-spangled Curmudgeon notes that the Hammer (the House Majority Leader and the future representitive of Johnson Space Center) is pissed. But Rep. DeLay might not be in a position to do much.

UPDATE:The Adminstration spits the dummy. (Via Nasawatch.)
"If the final version of this bill that is presented to the President does not include adequate funding levels for Presidential initiatives, his Senior Advisors would recommend that he veto the bill."

Duncan Young @ 1:28:00 PM | Post a Comment (0 have been added)
Friday, July 16, 2004
  Twenty Years since the night that changed everything...


John Roughan reflects on New Zealand's bizzare Independence Day - the second of July, 1984.
The Wikipedia account of the implosion of the Muldoon Government is here.




Duncan Young @ 1:15:00 PM | Post a Comment (0 have been added)
Tuesday, July 13, 2004
  Oh My G-d

It had to happen someday. I get Adventist spam (truly a Great Disappointment):

Return-path:
...snip
Received: from mail.com (ip-47-061.guate.net.gt [200.12.47.61] (may be forged))
by mac.com (Xserve/smtpin12/MantshX 4.0) with SMTP id i6DMlbCa027875; Tue,
13 Jul 2004 15:47:38 -0700 (PDT)
Date: Tue, 13 Jul 2004 16:47:44 -0600
From: Adventist Friends
Subject: THE PAPACY IS THE ANTICHRIST THAT IOS TRYING TO DESTROY THE LAW OF
GOD. DN.7:25
Reply-to: adventist_believers@yahoo.com

SUNDAY IS THE DAY OF THE BEAST, SABBATH 7TH IS GODґS TRUE DAY. EX. 20.
...snip
ADVENTIST SENVENTH DAY DOCTRINE
...snip
GOD SAID: "Remember the Sabbath day, to keep it holy. Six days you shalllabor...
...snip
...the LORD blessed the Sabbath day and hallowed it." (Exodous 20:8-11)
...snip
SABBATH =GOD`S HOLY DAY (SATURDAY 7TH DAY) SUNDAY= DAY OF THE SUN (1ST DAY)
JESUS IS COMMING SOON , PREPARE THE DEAD WILL RESURRECT, THEY ARE NOT IN HEAVEN OR HELL
John 5 28
...snip
JESUS IS THE WAY NOT MARY OR THE POPE
...snip
JESUS IS THE CHIEF CORNERSTONE NOT PETER
...snip
THE PAPACY IS THE ANTICHRIST .
VICARIOUS FILII DEI = V(5)I(1)C(100)ARI(1)OV(5)S FI(1)L(50)I(1)I(1)D(500)EI(1) 5+1+100+1+5+1+50+1+1+500+1=666
...snip - numeralogy!! Cool!!
ALL THE CATHOLIC SYSTEM IS A COPY OF BABYLON`S RELIGION ITS THE MOTHER
OF THE HARLOTS. SHE KILLED MILLIONS CHRISTHIANS
...snip
CATHOLIC CHURCH IS THE ANTICHRIST THAT CHANGED THE LAW OF GOD .
...snip
DON`T CALL FATHER TO THE POPE OR PRIESTS
...snip
THE TRUE PEOPLE OF GOD KEEPS THE 10 COMMANDMENTS AND THE FAITH OF JESUS



Complete with anti-spamblocker spelling mistakes. I expect viruses with pressed white shirts and ties to show up in my inbox anyday now...

This is nearly as exciting as when I got my first dead-African-dictator spam!

Duncan Young @ 3:52:00 PM | Post a Comment (0 have been added)
Sunday, July 11, 2004
  Number 2! Number 2!

Well that was a turnround! In the triangular West Indies/England/New Zealand pajama-party*, the Kiwis were unbeaten, dumped their hosts out of the final and went on to crush the Windies by 107 runs. The Black Caps are now second only to the World Champion Australians in the short form of the game.
*One day cricket, being largely derived from Australian media magnet Kerry Packer's failed attempt to buy the nobel game of cricket and turn it into a commercial cash cow in the '70's, differs from traditional Test cricket in that the teams wear bright uniforms of different colors (*GASP!*) instead of the traditional white, the teams often play in the afternoon and night under lights so the exciting bits end up in primetime (*SHOCK!*), and people actually watch it (*HORROR!*). The emphasis is on runs (points) rather than wickets (removing batsmen) so there is a lot of big hitting, conservative bowling, and spectacular fielding. New Zealand's traditionally fragmental bowling attack has always favoured the so-called "dibly-dobly" slow, accurate bowling that literally bores the opponent out of the game, and while New Zealand's batting is not terrifying, the fielding has always been consistent - and was the decisive factor in this tournament. Unfortunally Test cricket requires the Big Guns bowling, and while England had Steve Harmison, New Zealand's secret agent disintergrated at the start of the tour.
C'est la vie.

Duncan Young @ 8:13:00 PM | Post a Comment (0 have been added)
Wednesday, July 07, 2004
  A mystery solved?

After T-0, Cassini took distant images of all the major icy moons. The inspection was cursory, with the exception of Iapetus, which was imaged repeatedly with multiple polarizations and exposures from a distance of 3 million km. Iapetus, discovered by the original Cassini, is a solar system oddity. It is a cosmic heliograph, more than ten times brighter on one side of its orbit than the other. Arthur C. Clarke would use the apparent hemispheric difference as a major plot point in the novelization of 2001: A Space Odyssey. The Voyagers would reveal that the leading hemisphere (in terms of its orbit around Saturn) of Iapetus is smeared with dark red material - similar to that which comprises the surface of Phoebe and (possibly) the sparser rings of Saturn. Establishing the formation of this material is one of the primary goals of the Cassini mission. While endogenic (volcanic) origins for this material, named Cassini Regio, have been proposed, exogenic mechanisms (where the stuff is dumped onto the surface from somewhere else in the Saturn system - probably Phoebe) seem more likely (e. g. Bell and others, 1985).

This image, the perhaps auspiciously designated N00006667, is the first image to show detail in Cassini Regio. An unfiltered short exposure, it plainly reveals a large multiring basin, almost directly on the Saturn facing point, within the eastern margin of the darkened area. Some speculations: if you dump a Phoebe equivalent at high speed into the 'near' side of Iapetus, most of the ejecta will head inward, and accelerate longitudinal with respect to the moon due to Kepler's Laws (not much will directly stick, as Iapetus' gravity is too low). But Iapetus' gravity will be sufficient to stretch out the orbits of ejected material, so a cloud of PhoebeJunk will end up in orbit ahead of Iapetus. This will then congeal on Iapetus' leading edge.

Cassini is scheduled for a close encounter with Iapetus, examining the edge of Cassini Regio in detail, during mid 2007, which will test this, and other hypothesis. But I suspect monolith-building aliens are now unnecessary.


Duncan Young @ 2:41:00 AM | Post a Comment (3 have been added)
Tuesday, July 06, 2004
  Correction of the year

CLARIFICATION: It has come to the editor's attention that the Herald-Leader neglected to cover the civil rights movement. We regret the omission.


Today's New York Post might come close...

Duncan Young @ 4:03:00 PM | Post a Comment (3 have been added)
  Titan tantilizes...

The T-0 flyby, which had Cassini arcing under Titan, has confirmed some suspicions (ISS observations of Titan's south pole has a small system of cloulds, indicating that locally the temperatures in the moon's nitrogen atmosphere dive below the triple point of methane), but provided other problems. Scattering in the atmosphere will apparenly limit the use of the ISS cameras in two ways - scattering of reflected light from the surface as photochemical smog blurs abedlo details, and the same overcast washing out the sun as seen from the surface - meaning no shadows. All this means the believability of Titanian photointerpretation is going to be somewhere between Mars as seen by Lowell and Mariner 4.

VIMS, the lower resolution spectometer, however has managed to throw a spanner in the works. Previously, the thinking had been that the darker equatorial areas might be seas of ethane, produced by the photolysis of the methane in Titan's atmosphere (e.g. see Roe et al. 2004 , paragraph 11, or here (Ethane is liquid in the conditions predicted at Titan's surface). Apparently, though, these dark bands are composed of water (which at 94K is no way liquid), while organic material is strewn over the 'bright' temperate regions. Which means we literally had Titan backwards...

If it is true that the dark bands are solid, it increases the chances that the probe Hugyens will survive on the surface - liquid ethane's high thermal conductivity would quickly freeze the probe to death. Although the scientists involved might trade those minutes on the surface for a glimpse of an alien ocean...

The lack of obvious craters in the ISS images is also intriguing*, although the lack of shadows means that this hasnt been confirmed. The decider will be the RADAR instrument, a SAR much like than on Magellan operating at 2.2 cm wavelength that will scan Titan on the frequent flybys (at 338,922 km, this particular encounter was too distant). RADAR and ISS point in different, fixed directions, so they cannot be used at the same time. The results of this flyby may make the choice easier.
*a standard scientific word meaning we dont even begin to understand the data yet, but give us more money and we might be able to invent something.

Duncan Young @ 1:06:00 AM | Post a Comment (0 have been added)
  Baghdad for a Night


July 4th in Duluth was inconsistently wet and brutally overcast. Us travel deprived sorts gathered at the Langer's apartment and held forth over salad, cupcakes, light beer and barbecue adventurously grilled in the brief clearings. A good time was had by all, as shop talk was generally avoided. The postponement of the Main Event due to the relentless blah over the Twin Ports was offset by the fact Minnesotans have recently relegalised fireworks for themselves - and thus gone a bit potty. The evenings of the last week has been non-stop snap, crackle and BOOM, with a climax last night resembling Shock and Awe in Baghdad. Every street-corner, ridge top and patio, was blazing as the locals braved the rain to Blow Sh*t Up. In all directions. You never knew where to look - damn that slow speed of sound! And those trees that cover this town!
Standard dialog:
BANGCLATTERSIZZLE - "where was?!- There! Oh....behind that pine....sounded spectacular...

Occasional fireworks did make it above the tree-line.

I've always regretted the virtual banning of private fireworks in New Zealand - I have fond memories of the district of Ratapiko gathering to Blow Sht*t Up at the Corlett's farm, celebrating Guy Fawke's Day*. First they came for the Double Happies, then the skyrockets - before you knew it, you couldn't even get a sparkler to save yourself. But seeing Duluth dissolve into a flashing, sulfurous smog I have second thoughts...

I actually didnt know that the Main Event had been rescheduled for tonight until the windows of my office started bouncing at ten past 10. Again the trees were in the way but I did get this view from the top of the Alworth Planetarium.
*Either a celebration of the survival of British democracy or the burning of Catholics. Not that Independence Day is that much more morally superior: One of the whines in the the Declaration:
For abolishing the free System of English Laws in a neighbouring Province, establishing therein an Arbitrary government, and enlarging its Boundaries so as to render it at once an example and fit instrument for introducing the same absolute rule into these Colonies...
is about those all those nasty Papists in the Lower Canada practicing their pursuit of happiness.
The picture above was taken last year in Washington DC - where I engaged in an orgy of bad photography/abstract art trying to capture fireworks on pixels. My conclusion 108 images later - use a tripod (unless you are pushing the whole abstract bit).

Duncan Young @ 12:03:00 AM | Post a Comment (3 have been added)
Friday, July 02, 2004
  Day Two in Saturn Orbit


Press conference: First announcement (from Don Shemansky of the UVIS team) - from neutral oxygen observation, the diffuse E-ring apparently doubled in mass (to 10, 00 tonnes of oxygen) in January - before returning to normal in a matter of four months. As the lifetime of 1 micron particles is estimated at 40 days, they estimate that 100 million years is required for the decay of the entire E-ring (gotta be some huge assumptions here). Speculation about meteor impact, no mention of the Obvious, Out-There Candidate - the snow-covered moon, Enceladus, that orbits at the heart of the E-ring. Is this evidence for geysers? Closer encounters with this target next year.

Shemansky is causing the press folk's heads to explode. "Plasma sheet", "Cluster ions", "Adiabatically" - MATH IS HARD....

VIMS - The composition of the rings - bright parts are water ice superimposed of a thin dark 'dirt' that fills the gaps. 'Dirt' is same ferrous iron stuff as found on Phoebe. No carbon dioxide or organics yet.

ISS - In the approach, a streamer of ring material was identified attaching the thin F-ring to the shepherd moon Prometheus.

Meteorology...Winds and temperature structure.

ISS again - Titan. Approach map at 35 km/pixel doesn't show impact craters. If the dark stuff is liquid, then Titan, like Mars and Venus, has an equatorial rift system. T-0 encounter will get a factor of ten improvement resolution over 360E/-65N - if the atmosphere is clear at the target wavelengths.

Duncan Young @ 11:11:00 AM | Post a Comment (0 have been added)
Thursday, July 01, 2004
  Newton's Symphony


..Or Leibniz's punk-rock!!! This is apparently the edge of the Encke Gap - imaged at a couple of hundred meters per pixel last night in the frantic imaging after SOI.
Dark side of the rings, light is diffusely scattered sunlight, dark is void or opaque, and the rippled bizzaro crap in between is anyone's guess. The moonlet Pan is supposed to rummage through these part - I didn't realize that included rucking up the local carpet!!

UPDATE: Peter wonders what the hell I was smoking when I wrote this.

Briefly, "Newton's symphony" - Saturn's rings are basically an enormous gravitational musical instrument, being played by various moons via the father of differentiation's magical force. F=ma, g=GMm/r^2 etc. etc.

Leibniz, the inventor of intergration and the concept of energy, was his close Swedish rival and contemporary- and the complexity and apparent fubarness of the rings suggests melodies distinctly nonclassical.

SOI, is, of course, Saturn Orbit Insertion.

If you look at the stuff between the black (the Encke gap) and the density wave (the parallel lines) it is, well, weird. Cross cutting waveforms at the km scale. They look a bit like actual topographic features - corrugations on the ring plane at small scales. The gap itself is cleared by the 12-km wide moon Pan, which was found in old Voyager images in 1995.
A broader view of the gap is here ; the spiral standing wave is being spawned by Pan - rumoured to have been 20˚ of longitude away when the image was taken.

Duncan Young @ 7:27:00 AM | Post a Comment (3 have been added)