Space Sunday: ring grazing and exoplanet gazing

On July 19th, 2013, Cassini captured this remarkable shot of Saturn and its entire ring system as they eclipsed the Sun. captured at a distance of 1.2 million km (746,000 mi) from the planet. It spans a distance of 651,591 km (404,880 mi) across and uses 141 wide-angle shots collected over a 4-hour period, and shows the haze of Saturns's outer most "E" ring and, inward of it, the "G" ring, with Earth a tiny dot (arrowed) sitting between them. The more discrete ring system from the "F" ring through to the innermost "D" ring are visible, together with seven of Saturn's moons, of which two are ringed: Enceladus, on the left (see below) and Tethys, lower left). The colours seen are true, and have not been artificially enhanced Credit: NASA/JPL / Space Science Institute
On July 19th, 2013, Cassini captured this remarkable shot of Saturn and its entire ring system as they eclipsed the Sun. Taken from a distance of 1.2 million km (746,000 mi) from the planet, it spans a distance of 651,591 km (404,880 mi) across and uses 141 wide-angle shots collected over a 4-hour period. In it can be seen the haze of Saturn’s outermost “E” ring and, inward of it, the “G” ring, with Earth a tiny dot (arrowed) sitting between them. The more visible rings, “F” ring through to the innermost “D” are visible, together with seven of Saturn’s moons, of which two are ringed: Enceladus, on the left and Tethys, lower left – click for full size to see clearly. The colours seen are true, and have not been artificially enhanced. Credit: NASA/JPL / Space Science Institute

In 2005, along with friends, I attended a dinner at which a UK scientist, John Zarnecki, was honoured. His name might not be familiar to some, but Professor Zarnecki, currently serving as the Director of the International Space Science Institute in Berne, Switzerland, has been involved in a number of high-profile space missions, including the Hubble Space Telescope, the Giotto probe that visited Halley’s Comet, and UK’s Beagle 2 mission to Mars. He is currently leading the European ExoMars rover mission, scheduled for 2020.

However, it is probably with the NASA / ESA Cassini-Huygens mission that he has the deepest association. At the time of the dinner, Professor Zarnecki had already been involved in that programme for fifteen years. His primary responsibility was the Huygens probe, which became the first vehicle to land there in January, 2005, and still holds the record for the furthest landing from Earth a spacecraft has so far made.

I mention this, because while the Titan surface mission effectively came to an end 90 minutes after the lander arrived there, the Cassini vehicle has remained in operation around Saturn and its moons, gathering a huge amount of data in the process. However, its own mission is now coming to an end after almost 20 years. In September 2017, Cassini will complete its last full orbit of Saturn and then fall to is destruction.

Saturn's complex ring system, the gaps between them crated by a mixture of so-called "shepherd moons" in orbits between the rings and stablising and destabilizing orbital resonances caused by Saturn's larger moons.
Saturn’s complex ring system, the gaps between them crated by a mixture of so-called “shepherd moons” in orbits between the rings and stabilising and destabilizing orbital resonances caused by Saturn’s larger moons.

Before then, however, and starting on November 30th, 2016, the orbiter will commence the penultimate phase of its mission. Having gradually shifted itself into a more polar orbit around Saturn Cassini will commence a series of “ring-grazing orbits”, coming to within 7,800 km (4,850 mi) of what is regarded as the outer edge of Saturn’s major series of rings, the F-ring.

These orbits, which will extend through April 22nd, 2017, will see the spacecraft dive through the more diffuse G-ring once every seven days for a total of 20 times in what will be the first attempt to directly sample the icy particles and gas molecules which are located at the edge of the rings and also image the tiny moons of Atlas, Pan, Daphnis and Pandora, which play a role in “shepherding” the rings around Saturn.

Over time it will slowly close on the outer edge of the denser F-ring, until in March and April 2017, it is passing through the outer reaches of that ring, some 140,180km (87,612.5 mi) from the centre of Saturn. The F-ring is regarded as perhaps the most active ring in the Solar System, with features changing on a timescale of hours.

A 2007 artist impression of the aggregates of icy particles that form the 'solid' portions of Saturn's rings. These elongated clumps are continually forming and dispersing. The largest particles are a few metres across. Credit: NASA/JPL / University of Colorado
A 2007 artist impression of the aggregates of icy particles that form the ‘solid’ portions of Saturn’s rings. These elongated clumps are continually forming and dispersing. The largest particles are a few metres across. Credit: NASA/JPL / University of Colorado

Exactly how the majority of Saturn’s rings formed is still unknown;, with ideas focused on one of two theories. In the first, the material in the rings is the original material “left over” from the formation of Saturn and its larger moons, pulled into a disc around the planet by gravitational tides. In the second, the material is all that remains of a form er – called Veritas after the Roman goddess –  which either crossed the Roche limit to be pulled apart by gravitation forces or was destroyed by the impact with another body such as a large comet or asteroid.

However, in both of these cases it is not unreasonable to assume that the material making up the rings would be of a mixed nature: dust, ices, rocky matter, etc. However the majority of the ring matter is icy particles, with little else. This has given rise to a variation on the destroyed moon theory: that the particles are all that remains of the icy mantle of a much larger, Titan-sized moon, stripped away as it spiralled into Saturn during the planet’s formation.

Geyser on Enceladus, orbiting within the E-ring through vast amount of ice particles into space, replenishing and supporting the E-ring. Credit: NASA/JPL / Space Science Institute
Geyser on Enceladus, orbiting within the E-ring, throw vast amounts of ice particles into space, replenishing and supporting the E-ring. Credit: NASA/JPL / Space Science Institute

Continue reading “Space Sunday: ring grazing and exoplanet gazing”

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From Baker Street to the Baltic with Seanchai Library

Enter the lounge at 221B Baker Street to join Seanchai Library for more Holmesian adventures
Enter the lounge at 221B Baker Street to join Seanchai Library for more Holmesian adventures

It’s time to kick-off a week of story-telling in voice, brought to our virtual lives by the staff and volunteers at the Seanchai Library. As always, all times SLT, and events are held at the Library’s Second Life home at Bradley University, unless otherwise indicated.

Sunday, November 27th, 13:00: Tea-time at Baker Street

Tea-time at Baker Street sees Caledonia Skytower, John Morland and Kayden Oconnell open the pages of the second full-length novel by Sir Arthur Conan Doyle featuring Sherlock Holmes and John Watson. Originally commissioned for Lippincott’s Monthly Magazine, for which it was serialised under the original title The Sign of the Four; or The Problem of the Sholtos. This was reduced to The Sign of the Four in later serialisations and when published in book form in 1890 – a title which itself was further abbreviated to The Sign of Four for various film and television adaptations.

Sign-of-fourIn 1888, Mary Morstan comes to Sherlock Holmes seeking his assistance in two matters. The first is with regards to her father. Having returned safely from India in 1878, Captain Arthur Morstan had arranged to meet his daughter at the Langham Hotel, London – but he had vanished from the hotel prior to her arrival. In the decade since, no trace of his whereabouts has ever been discovered.

However following his disappearance – and possibly pursuant to it – is the second reason for Miss Marstan’s visit. Every year from 1882 onwards, she has been in receipt of a single pearl, which started arriving after she had responded to a strange newspaper advert inquiring for her. The latest such pearl to arrive had come with a letter, indicating she had somehow been wronged, the sender asking to meet with her.

Holmes discovers that the pearls started arriving shortly after the death of a Major Sholto, who served with Arthur Morstan in India. His investigations leave him convinced there is a complex set of connections between Morstan and Sholto, which involves an Indian fortress, the names of three Sikhs, an Englishman by the name of Jonathan Small and Sholto’s two sons. If all that weren’t enough, it would seem that greed and treasure may lay at the heart of matters…

Monday, November 28th 19:00: Versus

Gyro Muggins and Trolley Trollop present a tongue in cheek story from a series about a witch who writes Romance Novels as a way to pay the bills. She and her 300 year old vampire boyfriend encounter a bit more trouble than rumours and back-biting at a Halloween party for people in her writers’ guild.

Tuesday, November 29th 19:00: Serafina and the Twisted Staff

Caledonia Skytower reads the second adventure for Robert Beatty’s young heroine, Serafina, published in July 2016.

serafina-2Introduced in Serafina and the Black Cloak, the titular heroine had, up until the events of that story, lived a secret life in the basement bowels of the manor house on Biltmore Estate. However, she was forced to reveal herself to the estate owner’s young nephew in order that together, they might discover why the children on the estate were mysteriously vanishing.

Now, just a few weeks after those events, Serafina and her new friends must confront a new danger, one worse than the Black Cloak.

In doing so, they well face tests that will strain friendships, while Serafina learns more about her unique talent and abilities, allowing her to grow from introspective “other”, to a young girl accepting of herself. Nor is she alone in her growth; Braeden also is able to come into his own, understanding his own particular gifts,

Intended for younger readers, the Serafina books have a richness of prose and an approach to storytelling guaranteed to keep readers – and listeners – of all ages enthralled. Join Caledonia to find out more!

Wednesday, November 30th 19:00: TBA

Check the Seanchai blog for details.

Thursday, December 1st

19:00: Joulutarina – The Life and Adventures of Santa Claus

Shandon Loring presents Julie Lane.s classic story for Christmas.

Nicholas the orphan becomes Nicholas the wood carver, whose job is to create a gift for every child in his small village on the Baltic Sea. As he grows older, explanations for many beloved Christmas traditions are woven into the story as the true spirit of Christmas is revealed.

21:00: Seanchai Late Night

With Finn Zeddmore.


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 November-December is Reach Out and Read, a non-profit organization that gives young children a foundation for success by incorporating books into paediatric care and encouraging families to read aloud together.

 

A journey to Let It Snow! in Second Life

Let It Snow!, Timamoon Arts; Inara Pey, November 2016, on Flickr Let It Snow!, Timamoon Arts – click any image for full size

For the last two years, a regular seasonal destination for the Pey household has been Milly Sharple’s Let It Snow!, and I’m happy to say that it is once again back, and Caitlyn and I donned our woollies and our boots to explore the delights that artist Milly Sharple has again cooked up to help people into the Christmas mood.

The venue this year is slightly different to those of the past: rather than occupying its own region, Let It Snow! has been relocated to the sky over Milly’s arts community of Timamoon Arts – but this doesn’t make it any less enchanting a place to visit; there’s just as much to explore, see and discover as ever.

Let It Snow!, Timamoon Arts; Inara Pey, November 2016, on Flickr Let It Snow!, Timamoon Arts

Journeys begin, appropriately enough, on the north side of the setting, where sits a little paved square with Christmas shop and coffee-house waiting to wrap visitors in their warm embrace after a wander through the waiting landscape. A gentle snow is falling, softening the outline of distant forested crags and peaks.

A rocky hill also raises it head and shoulders from the middle of the landscape, encouraging visitors to go either east or west around it, a path marked by rounded rocks and stone perhaps encouraging most to try that way first. Whichever way you opt to go – along stone-marked path or over virgin snow, rest assured the two routes will reunite on the far side of the hill.

Let It Snow!, Timamoon Arts; Inara Pey, November 2016, on Flickr Let It Snow!, Timamoon Arts

Eastward, over the snow, lies a romantic little gazebo across a frozen stream, and open countryside sweeping around to a small park with carousels and merry-go-rounds. Milly’s collection of Snowboys are one again at play here, and a pair of little figure up on the slope a duet sing carols.

Westward, the path swings past a snow-laden house looking out over frosted trees to where a converted greenhouse welcomes couples and groups into its warmth. Follow the path beyond these, and it’ll take you by way of Santa’s grotto to where it branches, one arm leading its way up the rocky slope of the central peak, the other pointing the way to a crystal palace glittering in the snow, waiting to welcome visitors to the events which will be held within.

Let It Snow!, Timamoon Arts; Inara Pey, November 2016, on Flickr> Let It Snow!, Timamoon Arts

Should you feel in the mood, a frozen pond offers the chance for ice skating, whiles signs and givers can be found through offering wearing sleds and skis for the venturesome. For those fancying something a little less exerting, the carousels and merry-go-round mentioned above might be just the ticket!

With swings and snugs and seats scattered throughout, Let It Snow! is a place which encourages folk to tarry; Caitlyn and I watched the world walk and run by from the cosy blankets of a sleigh.

SLurl Details

Second Life Horizons land auctions, one week on

Horizons: looking at the auctions to date
Horizons: looking at the auctions to date

On Tuesday, November 15th, the Lab launched the Premium members’ Horizon community, a “retro-futuristic” environment featuring 36 residential regions each with 24 parcels available for auction to Premium members. The auctions opened on Friday, November 18th, with parcels being auction in batches.

One week on, and a total of 87 parcels have been or are up for auction, of which, 67 have closed as of Friday, November 25th, marking the first week of auctions. Whirly Fizzle and I have been tracking things during the week, so we’d thought we’d offer an update on how things are going.

Auction Results Fri Nov 18th Through Friday Nov 25th

GENERAL INFORMATION
Total parcels Auctioned to date For re-sale For rent Commercial Residential Unknown
864 67 26 13 5 11 12

Notes

  • “Unknown” parcels are those which appear likely to be put up for sale or rent. Of these:
    • Four have been obtained by land sellers, with 2 initially put on sale, then withdrawn.
    • Five have been obtained by land renters but are not currently for rent.
    • Three could go either way.
  • Of the commercial parcels, four appear to be rentals; one is parcel holder / store operator.
  • “Residential” refers to those parcels purchased by individuals without any obvious land marketing in their profiles & who have not won auctions for other parcels. These could still be sold / rented out or used commercially.

 

RESULTS BY LOT
Lot Parcels Top bid
Lowest bid
Average bid
Av sqm bid
Total L$ paid
1 10 57,270 30,133 43,689.80 42.66 436898
2 12 65,010 30,121 39,976.75 39.04 479721
3 15 40,030 29,510 (x3) 31,306.73 28.65 469601
4 10 42,670 31,110 (x4) 35,464.50 34.53 354645
5 10 40,110 26,010 (x2) 37,751.80 30.91 317518
6 10 33,009 27,887 29,790.20 29.09 297902

 

REVENUE
 Date No of lots
L$ raised in auction Approx US $
 Nov18th-25th 67 2,356,285 9,000

Notes

  • Taking the lowest bid price for all auctions closed to date, and applying it to all remaining parcel yields a potential total revenue of L$24,582,224 / approx US $94,500.
  • Taking a median bid price of L$36,330 based on closed auctions to date, and applying it to all remaining parcels yields a potential total revenue of L$28,955,010 / approx US $111,365.

 

PARCEL RE-SALE PRICING, FRIDAY NOV 25
Total Av sqm auction price Av sqm sale price
Av sqm mark-up
Highest initial price Highest current price Price spread
26 28.05 57.38 104.56% L$100,000 (x3) L$99,000 (x1) L$33,000 (x4) – L$99,000 (x1)

Notes

  • The figures above are only a snapshot – re-sale prices are fluctuating; prices set for parcels auctioned in lots 5 and 6 are likely to be reduced.
  • Initially, 28 parcels were put up for sale. Two were withdrawn on Friday 25th.
  • Of the remaining 26 parcels currently for sale:
    • Six parcels were initially priced at between 25 and 3 times their auction price; all have had their re-sale price reduced by an average of 50%.
    • Four parcels have seen a reduction in price since first being placed for sale of between 2.5% and 21.52% per parcel.
    • Eight parcels are currently for sale at a median of 2.5 times their auction price (ave L$70,000 per parcel). current tends suggest these will be reduced.

 

PARCEL RENTALS, FRIDAY NOV 25
Total Rented to Date Upper rental price
Lowest Rental Price
Median Rental
13 4 L$835/w (x1) L$595/w (x4) L$775/w (x4) / L$795/w (x4)

 

Radegast: recovering Voice capabilities

Gentle Heron, second from the right encountered a Radegast Voice installation during the recording of a Designing Worlds special. Credit: Beq Janus
Gentle Heron, second from the right encountered a Radegast Voice installation during the recording of a Designing Worlds special. Credit: Beq Janus

Update, November 30th: Cinder Roxley has updated the Radegast installer to work with the most recent SLVoice package. See her comments here and here (following this article). There is also a separate blog post on her work, for easier future linking.

It was recently discovered that the Radegast client was no longer installing the SLVoice extensions with a new / clean installation. On hearing of the problem, Beq Janus and Whirly Fizzle decided to investigate, and thanks to their work, we now two workaround solutions. As they had put the effort into sorting things out, I asked them if either would like to write about the issue and the solution, and Beq, with Whirly’s blessing, agreed to do so.

by Beq Janus

A few days ago when I was invited to reprise my role as a videographer for a special episode of Designing Worlds on the Future of Second Life, which will air in early December. The panel for the discussion included Gentle Heron of Virtual Ability Inc, the group who work to enable access to virtual worlds for those who, through disability or illness are unable to make ready use of regular viewers.

During the show, Gentle urged Linden Lab and us all to look for ways to make Virtual Worlds more accessible, remarking, somewhat fatefully, that many of her communities are limited to a single, troubled viewer, Radegast.

A subject of reviews in this blog, Radegast is a lightweight, extensible client which has been the ideal foundation for the disabled communities to build upon. It boasts an impressive set of speech to text and text to speech integrations and can be integrated with other devices such as braille screen readers. Sadly, Latif Kalifa, Radegast’s creator, passed away earlier this year and despite the code being open source, no-one has yet stepped forward to maintain it at a time when the Lab viewer is moving ahead in leaps and bounds, with the risk that non-maintained viewers and client might lose functionality.

 Radegast client is the leading lightweight client for many users with disabilities
Radegast client is the leading lightweight client for many virtual world users with disabilities

As if to underline this, Gentle fell silent towards the end of the show, as she was dealing with a number of users who were reporting they were unable to use Voice with Radegast as it was failing to install the all important SLVoice extensions. While I am unfamiliar with Radegast, I offered to try looking into it for Gentle.

SLVoice is a pre-built binary package supplied by Vivox and distributed by Linden Lab. During the summer, it had been upgraded to address some security concerns and so it seemed likely to me that Gentle’s problem might be that the older SLVoice package had been deprecated and removed from the download server. Sure enough, a quick check on the package URL resulted in  the dreaded 404 not found error. I sent an email to Oz and Patch Linden asking them to confirm whether older versions of SLVoice had been moved.

The next day Oz confirmed that all old SLVoice packages were still available and nothing had changed. Whirly Fizzle, the powerhouse behind Firestorm QA, leapt into action: she cracked open the installer and discovered the URL actually pointed to a separately hosted Voice package which was no longer available, causing the Voice installation to silently fail during a new or clean Radegast installation as a result. However, Whirly also found a working back-up archive we could perhaps use. Unfortunately, neither Whirly or I are C# coders and cannot update the installation package directly; so how could we get a Radegast installation to work with the back-up Voice package?

I hit on the idea of first installing the backup package that Whirly had discovered, and then running the standard Radegast installer. Success! So, for anyone who is performing a clean / new install of Radegast and needs Voice, I’ve produced a set of instructions – see the link below. There is, however, more.

I mentioned above that Linden Lab had updated the SLVoice packages over the summer to deal with security concerns. Because of this, older versions of SLVoice are to be blocked from connecting to the service, and Radegast would once again be without a Voice option. Knowing this, and never one to leave a job half done, Whirly successfully tested my approach using the most recent SLVoice package available from the Lab, and confirmed it will also work.

This means that providing that there is no internal dependency within Radegast on the legacy Voice package, we now have an upgrade path for Radegast users that will ensure continued voice support after the block on older SLVoice packages comes into force. To help ensure people know what they need to do, Whirly’s instructions can also be found in the link below.

Radegast Voice Installation Instructions.

A Plea to Developers

These instructions are only a workaround. We still need to find a way to have Radegast install the correct Voice extensions automatically, as a part of the client install process. So, if you are a C# (C-Sharp) developer and are willing to spare a few hours looking at this, please take a look at the Radegast codebase and see if there is a way to incorporate the correct binaries into an installer package. Thank you.

With grateful thanks to Whirly Fizzle.

Lumiya 3.2: Google Cardboard support

lumiya-logoOn Thursday, November 24th, Alina Lynette release Lumiya 3.2, which brings with it support for Google Cardboard and compatible VR kits and headsets!

Even though the Lab has – at least for the foreseeable future – put work on a VR headset compatible version of the viewer off to one side, interest in seeing Second Life from the “inside”, as a fully immersive VR experience remains high, and Alina has sought to rise to the challenge with Lumiya.

There are obviously a couple of caveats to using the application in VR mode:

  • You really need a suitable headset
  • You need a device with Andorid 6.0+ Marshmallow installed

I have Android 6, but I don’t have any form of headset, Cardboard or otherwise, that I can use with my device – which happens to be a Nexus 7 2013 HD Tablet – a little clunky for any headset device, although there are some out there. Nevertheless, I gave the new capability a go as best I could.

To enter VR mode on a suitable device, simply log-in to Second Life on Lumiya, and then go to the 3D view (Menu icon, top left > 3D view).

Access the VR mode in Lumiya 3.2 is done via the Action menu, when in the 3D view
Access the VR mode in Lumiya 3.2 is done via the Action menu, when in the 3D view

Once the view has loaded, tap the Action menu icon (top right) and select Virtual Reality Mode. The first time you do this, you will be prompted whether you want Lumiya to handle speech-to-text conversion for you to allow you to “converse” in-world, via the “microphone” button. You can deny this if you wish, but it will leave you with no means to converse.

Whether you Allow or Deny the speech-to-text conversion, Lumiya will switch output to a stereoscopic format, suitable for use with Cardboard devices and the likes of the Samsung Gear VR. Three buttons are projected into the field-of-view:

  • Microphone – for enabling speech-to-text translation
  • Finger – for touching things
  • Chat bubble for text-mode chat.

Any of the three can be activated by staring at the required button – it should be highlighted when your stare is registered – then pressing the Cardboard device flap (or button / magnet actuator in the case of a Cardboard V1 device). If you’re trying Lumiya in VR mode without a headset, you can try staring at the button and touching the top of the screen between the left and right view – how successful you might be is debatable, and dependent upon on a number of factor (ambience background light, etc).

Movement is achieved by tapping and holding the same area of the device (or screen, if not using a device) while not looking at any of the buttons. You will then move in the direction yo are looking. Release the device / screen to stop.

Lumiya in VR stereoscopic mode. When using a Cardboard or similar device, staring at the on-screen buttons and pressing the flap / button on the device should activate the required function. Or if you're not using a device, you can try staring at a button and touching the screen where indicated (approximately) by the red circle. Pressing this point (or the flap / button on a device) will allow you to walk in the direction to are looking
Lumiya in VR stereoscopic mode. When using a Cardboard or similar device, staring at the on-screen buttons and pressing the flap / button on the device should activate the required function. Or if you’re not using a device, you can try staring at a button and touching the screen where indicated (approximately) by the red circle. Pressing this point (or the flap / button on a device) will allow you to walk in the direction to are looking

To exit VR mode, manually tap the X icon top left of the screen. The gear icon, top right can be manually used to access the Google Cardboard application for calibrating your headset device, if required (and if installed on your device).

The 3.2 release also includes a bug fix to prevent a black screen in the 3D world view when anti-aliasing is enabled.

As I am without a suitable headset kit / device, I was unsuccessful trying to test the button functionality, but the walking certainly worked for me without a hitch. Adding VR to Lumiya might seem to some a bit of a niche thing, but that doesn’t stop it from being a fun addition. It certainly further demonstrates what can be achieved with the application, and kudos (again) to Alina for her work.

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