Duck and Cover

Sunday October 19th marked the culmination of what is regarded as one of the most unique astronomical events to take place in human history – so unique, some commentators believe it may only happen once every million years or so: the opportunity to study something which may have existed before the Earth was created.

For the last several months, comet Siding Spring has been under observation as it hurtles through the solar system at an acute angle relative to the plane of the ecliptic – the imaginary line along which the planets orbit, and on Sunday October 19th, it made its closest approach to Mars, passing just in front of the planet relative to the Sun.

Siding Spring was first identified by Australian astronomer Rob McNaught, and bears the name of his observatory as a result, although officially it is catalogued as C/2013 A1. Since then, it has been under observation from a veritable armada of international space craft, and its passage past Mars presents further unique opportunities for observation and data-gathering.

Siding spring is a comet originating in the Oort cloud, and beleived to be making perhaps its first foray into the inner solar system, passing inside the orbit of Jupiter
Siding spring is a comet originating in the Oort cloud, and believed to be making perhaps its first foray into the inner solar system, passing inside the orbit of Jupiter

The comet has been identified as coming from the Oort cloud (or the Öpik–Oort cloud, to give proper recognition both astronomers who initially and independently postulated its existence). This is a spherical cloud of debris left-over from the creation of the solar system, occupying a huge area starting some 2,000-5,000 AU (2,000 to 5,000 times the distance from the Earth to the Sun) and extending out to around 50-100,000 AU – or about one light year away. Thus, Siding Spring represents some of the material “left-over” from the formation of the solar system 4.6 billion years ago – older than the Earth itself. In fact, such is the distance of the Oort cloud from the Sun, that some postulate the much of the material within it may actually come from stars which shared the same “stellar nursery” as the Sun.

There is nothing unique per se about comets coming from the Oort cloud – it is one of two places from which all comets originate, the other being the Kuiper belt (or Edgeworth–Kuiper belt, as it is also known in recognition of the two astronomers to postulate its existence in the form we now know it has). A disk of material also from the early history of the solar system, the Kuiper belt orbits the Sun at a distance of around 30-50 AU, and gives rise to “periodic” comets. These are comets which circle the Sun in periods of up to 200 years. Two of the most famous Kuiper belt comets are comet Halley, with it 76-year orbit, and comet Shoemaker-Levy 9, which broke-up during a close approach to Jupiter in 1992 prior to colliding with the gas giant in 1994.

Siding Springs passage through the solar system
Siding Springs passage through the solar system

What makes Siding Spring of interest to astronomers is that this is probably the first time in its long, cold history it has ever come inside the orbit of Jupiter since it was first nudged out of the Oort cloud. This led Dr Michael Brown, an astronomer at Monash University, to describe the comet as “essentially a refrigerator of pristine parts of the creation of the solar system. The particles it gives off are effectively opening up the door of the fridge so we can see what the solar system was like 4.6 billion years ago.”

John Grunsfeld, former astronaut and associate administrator for NASA’s Science Mission Directorate in Washington was equally enthused by the comet’s passage, referring to it as “a cosmic science gift that could potentially keep on giving.” Speaking at a press conference held earlier in the year to discuss NASA’s plans to observe Siding Spring, he continued, “The agency’s diverse science missions will be in full receive mode.” He went on, “This particular comet has never before entered the inner solar system, so it will provide a fresh source of clues to our solar system’s earliest days.”

The chance for scientific discovery notwithstanding, the comet’s path was initially a cause for concern, at least in terms of Mars’ future. Early attempts to track the comet’s likely route  “up” through the solar system suggested that rather than passing the Red Planet, Siding Spring would in fact smash into it.

Had the comet struck, estimates suggest it would have created a crater between 10 and 15km in diameter, depending on the actual size of the comet’s nucleus, thought to be between 700m and 1km across.  While that is certainly enough to result in quite an extraordinary bang and some severe changes in the Martian atmosphere (not to mention the sizable dent it would make in the planet’s surface), Mars has actually withstood much larger impacts in its time.

Take Hellas Basin, for example. It is the largest visible crater in the solar system, some 2,300km (1,440 miles) across, and with an ejecta ring some 7,000km (4,375 miles) across. It is believed to have been created by the impact of an asteroid some 400km (250 miles) in diameter.

The Hellas Basin, shown in purple in the image of the right, above. Deeper than Mount Everest is tall, the depression was likely caused by the impact of an asteroid some 400km across. The impact also resulted in the Tharsis Bulge on the opposite side of the planet, and shown in red in the image on the left, topped by the three massive Tharsis volcanoes, and split by the 5,000km length of the Vallis Marineris
The Hellas Basin, shown in purple in the image of the right, above. Deeper than Mount Everest is tall, the depression was likely caused by the impact of an asteroid some 400km across. The impact also resulted in the Tharsis Bulge on the opposite side of the planet, and shown in red in the image on the left, topped by the three massive Tharsis volcanoes, and split by the 5,000km length of the Vallis Marineris

As Grunsfeld noted, such is the scientific opportunity presented by the comet, that NASA has put a significant number of assets in the front line of tracking and observing Siding Spring. These include the Hubble Space Telescope, the Spitzer infra-red space telescope, the WISE infra-red space telescope, the Chandra X-ray observatory, the Kepler orbital observatory (used in the search for Earth-sized extra-solar planets) and more, as well a host of ground-based observatories.

Foremost in the front line, by dint of the comet’s close passage past Mars, are NASA’s orbital and surface vehicles there. Curiosity, Opportunity, the Mars Reconnaissance Orbiter (MRO), Mars Odyssey and MAVEN, together with Europe’s Mars Express and India’s MOM, are all watching the comet, although for the orbiting spacecraft, this comes with a degree of risk.

Siding Spring has been, and is, under observation by an armada of science probes and also from observatories on Earth
Siding Spring has been, and is, under observation by an armada of science probes and also from observatories on Earth – including these from NASA

Continue reading “Duck and Cover”

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A witch’s brew of tales, spiced with a sprinkling of sci-fi

It’s time to kick-off another week of fabulous story-telling in voice, brought to Second Life by the staff and volunteers at the Seanchai Library. and Seanchai Kitely.

As always, all times SLT / PDT, and unless otherwise stated, events will be held on the Seanchai Library’s home on Imagination Island.

Sunday October 19th – BOOFest! In Aid of Feed A Smile

BOOFest14It’s time to enjoy the 4th successive year of BOOFest!, Seanchai Library’s joint celebration with the folk at Branwen Arts Co-operative featuring spooky stories told around a blazing autumnal fire.Featuring a gathering of virtual story presenters at their spooky and scary best

This year’s BOOFest is being held at Lavender Fields, the home of Feed A Smile in Second Life, with all tips going directly to the work of LLK in Kenya.

Story sessions will include everything from classic authors of the ghostly to the macabre, from Bram Stoker and H.P. Lovecraft; through to contemporary writers such as Neil Gaiman. In addition, original works by SL authors Freda Frostbite, Dubhna Rhiadra, Caledonia Skytower, and Moon Aerandir will also be included.

One not to be missed – check the schedule on the StoryFests SL website.

Monday October 20th, 19:00: The Witches of Karres

witches of KarresGyro Muggins once again delves into James H. Schmitz’s mix of space opera, hard science-fiction and fantasy, all mixed together with a flavouring of humour. The original story, a novella, was first published in 1949, and 1996, Schmitz expanded it into a full-length novel with three further adventures, prior to the series spinning-off into two additional novels, The Wizard of Karres (2004), by Mercedes Lackey, Eric Flint, and Dave Freer, and The Sorceress of Karres (2010), again by Flint and Freer.

There’s an old saying that no good deed ever goes unpunished. Such is the case for Captain Pausert, inexperienced space trader, skipper (and sole crew member) of the old Venture. He’s just starting to feel he might make it as a trader dealing in cargo no-one else will handle when he is persuaded to take aboard three young girls who had been enslaved on the planet Porlumma …. and things go rapidly awry from then on.

Catch-up with Pausert’s adventures and Gyro Muggins pulls out a selection from the books. 

Tuesday October 21st,19:00 More Poe!

Caledonia Skytower settles down to read from the pages of the Master of the Macabre himself. Are you sitting comfortably with the lights down low?

Wednesday October 22nd, 19:00: Bellwether – Conclusion

  Constance Elaine Trimmer “Connie” Willis is an American science fiction writer. She is one of the most honored science fiction writers of the 1980s and 1990s. Her books have between them won 11 Hugo awards, seven Nebula awards and four Locus awards, making her the recipient of more major science-fiction awards than any other author.

Bellwether, published in 1996, was a Nebula ward nominee, brings together pop culture, love, chaos theory and a study of human behaviour. Dr. Sandra Foster studies fads and their meanings for the HiTek corporation, a company keen to find a means of predicting how fads happen so they might create one themselves and profit from it. Also working for HiTek, Dr. Bennet O’Reilly is studying monkey group behaviour and chaos theory. When a misdelivered package brings the two together, coupled with a series of unfortunate events, they engage upon a joint project involving a flock of sheep. Even so, more setbacks, disappointments and surprises are likely to arise before the answers to their questions are found…

Thursday October 23rd

19:00: Thrilling Tales

With Shandon Loring.

21:00 Seanchai Late Night

With Finn Zeddmore.

Saturday October 25th: Spooky Saturdays at Seanchai Kitely

09:00: Seanchai Kitely – Nocturnes

NocturesNocturnes marks Irish author John Connolly’s first anthology of short stories involving lost lovers and missing children, predatory demons, and vengeful ghosts, a latter-day grim reaper and vampiric wives – and much more besides.

Echoing genre masters such as M R James, Edgar Allen Poe, H.P. Lovecraft and Stephen King, Connolly delves into our darkest fears through a series of tales including The Underbury Witches, in which two detectives are faced with the ultimate in female evil and The Ritual of the Bones, where a boy at a boarding school who comes to face the dark side of the British class system. There are even two novella’s included in the volume, The Reflecting Eye, which sees the return of Connolly’s private detective hero, Charlie Parker, and the initial story within the book, The Cancer Cowboy, charting the progress of a modern-day grim reaper, a complex individual attempting to understand exactly who or what he is, and why he must be so.

Join Shandon Loring as he once more dips into Connelly’s tales to bring you another helping spooky stories.

10:00: The Graveyard Book

Join Caledonia Skytower as she continues Neil Gaiman’s 2009 Newbery Medal winning children’s fantasy novel, simultaneously published in Britain and America during 2008, which also collected the annual Hugo Award for Best Novel from the World Science Fiction Convention and the Locus Award for Best Young Adult Book selected by Locus magazine subscribers.

Nobody Owens, known to his friends as Bod, is a normal boy. He would be completely normal if he didn’t live in a sprawling graveyard, being raised and educated by ghosts, with a solitary guardian who belongs to neither the world of the living nor of the dead. There are dangers and adventures in the graveyard for a boy. But if Bod leaves the graveyard, then he will come under attack from the man Jack—who has already killed Bod’s family . . .

Again, please note both of these sessions are at Seanchai’s Kitely homeworld, as indicated in the title link, above.

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Please check with the Seanchai Library SL’s blog for updates and for additions or changes to the week’s schedule. The featured charity for September-October is Reading is Fundamental: seeking motivate young children to read by working with them, their parents, and community members to make reading a fun and beneficial part of everyday life.

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BURN2 Caravansary

BURN2 Caravansary -
BURN2 Caravansary – Daark Gothly’s celebration of the Arabian horse

BURN2 2014 opened its gates on Saturday, October 18th and will run through until Sunday October 28th.

As with previous years, the festival is spread across six regions, all in the familiar desert look, surrounded by sandy hills that add to the atmosphere and give more of a feel that the event is connected with the real life Burning Man festival.

The theme for this year is “caravansary”, with the press release on the festival noting:

This year, we will create a caravansary that occupies the crossroads of a dreamland: a bazaar of the bizarre, wherein treasures of every sort, from every land and age, flow in and out to be flaunted, lost, exploited and discovered. This is not a tourist destination, but a home for travelers who come here bearing gifts. Amid the twisting and the turnings of its souk, participants will come upon an inexhaustible array of teeming goods and unexpected services.

Anyone may pose as ‘merchant’ here, and anyone may play a ‘customer’, but nothing in this strange emporium shall have a purchase price — no quid, no pro, no quo — no trade at all will be allowed in this ambiguous arcade. According to a rule of desert hospitality, the only thing of value in this ‘marketplace’ will be one’s interaction with a fellow being.

BURN2 Caravansary - inside the Temple
BURN2 Caravansary – inside the Temple

There are the usual features for the event waiting to be found and experienced. These include the huge, hanger-like bulk of the Temple (set to burn twice on Sunday, October 26th at noon and 20:00 SLT), within which sits an intricate display of light, colour and statues, and before which stand images of Temples past; and the equally huge figure of the Man, awaiting his turn to burn on Saturday, October 25th, again at noon and 20:00 SLT.  There will also be the familiar and much-loved Lamp Lighters Processions twice daily (11:00 and 19:00 SLT most days), and the familiar mix of entertainments throughout.

Across the Playa, many of the builds have entered fully into the theme, offering tented shade, rich rugs, and places to sit and rest, much as traders on the great Asian trade routes may once have camped around the caravansaries to be found along their way and shared one another’s hospitality. Others are more whimsical in nature  – such as the Loch Nest Camel; Nessie with a hump, you might say…

You can find your way around the Playa on foot – just follow the grid tracks. If you prefer, you can hop aboard one of the tour balloons and drift around the regions; and if you feel particularly daring, you could grab a ride from one of the DMV (Department of Mutant Vehicles!) rezzers (look for the red signs).

To find out more about the inspiration behind builds and artwork in the Playa, check of the BURN2 website for descriptions. You can also use the Schedule page on the website to quickly see what is going on throughout the festival, and identify those events you’d like to attend.

BURN2 Caravansary - The Man
BURN2 Caravansary – the Man

About BURN2

BURN2 is an extension of the Burning Man festival and community into the world of Second Life. It is an officially sanctioned Burning Man regional event, and the only virtual world event out of more than 100 real world Regional groups and the only regional event allowed to burn the man.

The BURN2 Team operates events year around, culminating in an annual major festival of community, art and fire in the fall – a virtual echo of Burning Man itself.

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