Space Sunday: of life elsewhere and launches

Titan’s structure (via wikipedia)

Saturn’s giant moon, Titan, has been a source of speculation of decades. Shrouded in a dense, methane-nitrogen rich atmosphere, potentially harbouring a liquid water ocean beneath its crust, the moon has long be thought to have the conditions in which basic life might arise.

The joint NASA-ESA Cassini-Huygens mission has, over the span of thirteen years, added immeasurably to our understanding of Titan – and to the mysteries of its potential. In doing so, it has also provided us with evidence of processes taking place which are the precursors to the development of life. For example, we know that within Titan’s ionosphere, nitrogen, carbon and hydrogen are exposed to sunlight and energetic particles from Saturn’s magnetosphere. This exposure drives a process wherein these elements are transformed into more complex prebiotic compounds, which then drift down towards the lower atmosphere and form a thick haze of organic aerosols that are thought to eventually reach the surface.

However, while the drivers of the process are known, the nature of the process itself has been something of a mystery – one which an international team of scientists led by the University College London (UCL) think they now understand.  In Carbon Chain Anions and the Growth of Complex Organic Molecules in Titan’s Ionosphere the team identify Titan’s upper atmosphere contains a negatively charged species of linear molecule in Titan’s atmosphere called “carbon chain anions” – which, it has in the past been theorised, may have acted as the basis for the earliest forms of life on Earth.

The molecules were detected by CAPS, the Cassini Plasma Spectrometer, as the vehicle passed through the upper reaches of Titan’s atmosphere on a final flyby before commencing its “Grand Finale” of flights between Saturn and its rings. The discovery came as a surprise, as carbon chain anions are highly reactive, and should not survive long in Titan’s atmosphere. However, what particularly caught the attention of the science team was that the data show that the carbon chains become depleted closer to the moon, while precursors to larger aerosol molecules undergo rapid growth. This suggests a close relationship between the two, with the carbon chains ‘seeding’ the larger molecules – those prebiotics mentioned above – which then fall to the surface.

How complex molecules are thought to form in Titan’s atmosphere. Credit: UCL

“We have made the first unambiguous identification of carbon chain anions in a planet-like atmosphere, which we believe are a vital stepping-stone in the production line of growing bigger, and more complex organic molecules, such as the moon’s large haze particles,” said Ravi Desai, the lead author for the study in a press release from UCL.

He continued, “This is a known process in the interstellar medium – the large molecular clouds from which stars themselves form – but now we’ve seen it in a completely different environment, meaning it could represent a universal process for producing complex organic molecules. The question is, could it also be happening at other nitrogen-methane atmospheres like at Pluto or Triton, or at exoplanets with similar properties?”

With its rich mix of complex chemistry coupled with its basic composition, Titan is something of a planetary laboratory; one which probably mirrors the very early atmosphere surrounding Earth before the emergence of oxygen-producing micro-organisms which started the transformation of our atmosphere into something far more amenable for the advance of life. As such, the discovery of carbon chain anions in Titan’s atmosphere potentially confirms that long-held theory that they help kick-start the life creating processes here on Earth, and suggest conditions on Titan might allow the same to happen there. It also offers insight into how life might start elsewhere in the galaxy.

“These inspiring results from Cassini show the importance of tracing the journey from small to large chemical species in order to understand how complex organic molecules are produced in an early Earth-like atmosphere,” Dr Nicolas Altobelli, ESA’s Cassini project scientist, said in the same press release. “While we haven’t detected life itself, finding complex organics not just at Titan, but also in comets and throughout the interstellar medium, we are certainly coming close to finding its precursors.”

Dream Chaser ISS Flights target 2020 Commencement

Sierra Nevada Corporation (SNC) has confirmed than United Launch Alliance (ULA) will provide the veritable Atlas V booster as the launch vehicle for the Dream Chaser Cargo mini-shuttle, which will be joining fleet of uncrewed vehicles from America, Russia and Japan keeping the International Space Station (ISS) supplied with consumables, equipment and science experiments. The company also indicate that launches of the vehicle could start in 2020.

The Altas V – Cream Chaser Cargo launch configuration. Credit: United Launch Alliance

Dream Chaser was originally conceived to fly crews to and from the ISS as part of NASA’s commercial crew transportation joint venture with the private sector. Four companies vied for contracts to supply NASA with vehicles capable of shuttling up to six personnel to and from the space station. Despite being one of the most advanced of the designs in terms of feasibility and development, the Dream Chaser was not selected for that work, with NASA opting for the SpaceX Dragon 2 vehicle and Boeing’s CST-100 Starliner capsule.

However, support within the US space agency for the Dream Chaser continued, allowing SNC to propose the development of Dream Chaser Cargo, a revised version of the original concept, capable of supplying up to 5.5 tonnes of cargo to the ISS. In January 2016, in renewing its contract with SpaceX (Dragon) and Orbital ATK (Cygnus) for such resupply missions, NASA extended it to include SNC. This was followed a year ago by formal approval being given for Dream Chaser missions to the ISS, which allowed SNC to push ahead with testing of the revised vehicle.

Dream Chaser will launch atop the commercial Atlas V in its most powerful configuration, dubbed Atlas V 552, with five strap on solid rocket motors and a dual engine Centaur upper stage. The cargo vehicle will be held inside a five metre diameter payload fairing with its wings folded. Cargo will be carried both within the vehicle itself and in a support module mounted on the rear of the spacecraft, which will also house a docking adaptor for connecting with the space station. The latter will be supplied to SNC by the European Space Agency, which is also supplying NASA with the Service Module for the Orion multi-Purpose Crew Vehicle.

The Dream Chaser Cargo, built by SNC, and the International Berth and Docking Mechanism, to be supplied to SNC for Dream Chaser flights by the European Space Agency. Credit: SNC

In addition to flying up to 5.5 tonnes to the ISS, Dream Chaser Cargo will be able to return some 2 tonnes of equipment, experiments and other items from the space station to Earth, where it will make a conventional runway landing using the former space shuttle runway at Kennedy Space Centre – or any other suitable landing facility in the United States.

It is expected that Dream Chaser cargo will fly a total of six missions to the ISS between 2020 and 2024, when it is currently anticipated the space station will be decommissioned.

Continue reading “Space Sunday: of life elsewhere and launches”

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Mysterious house buyers, African adventures, divine sisterhoods

Seanchai Library, Holly Kai Park

It’s time to kick-off another week of storytelling in Voice by the staff and volunteers at the Seanchai Library. As always, all times SLT, and events are held at the Library’s home at Holly Kai Park, unless otherwise indicated.

Sunday, July 30th 13:30: Tea-Time at Baker Street

Tea-time at Baker Street continues with readings from The Casebook of Sherlock Holmes, the final set of twelve Sherlock Holmes short stories first published in the Strand Magazine between October 1921 and April 1927.

This week: The Adventure of the Three Gables.

Steve Dixie, a ruffian (and coward) visits 221B Baker Street in an attempt to intimidate Sherlock Holmes. Only things don’t go as planned.

Having received his strange visitor, Holmes quickly deduces that Dixie’s boss, one Barney Stockdale, is involved in a case involving the very place Dixie was ordered to warn Holmes away from: Harrow Weald. Seeing an opportunity, Holmes secures Dixie’s cooperation in matters, before setting out for Harrow Weald.

One there, Holmes meets with a Mrs. Mary Maberley, who has lived at Green Gables for two years in relative peace and seclusion, has been subject to some strange goings-on since her son, an attaché in Rome, died. Despite several houses in the neighbourhood standing empty, Mrs. Maberley has been approached by a man wishing to buy Three Gables and all its furnishings, and is willing to pay well above the market price – and the contract he would have her sign in order to sell the house would prevent her removing anything from it.

Discovering further connections to Barney Stockdale, Holmes sets out to unravel the mystery …

Monday, July 31st 19:00: A Boy Ten Feet Tall

Originally published in 1961 under the title Sammy Going South, and then later Find the Boy, W.H. Canaway’s novel is often referred to a “The Huckleberry Finn of Africa.” It became the basis for a 1963 British film Sammy Going South, starring Edward G. Robinson, which was released in the United States as A Boy Ten Feet Tall – hence the revised title for the book.

Born in the Suez region of Egypt, where he is orphaned, Sammy learns he has an aunt living in Durban, South Africa, and is determined to travel south to be with her.

Already distrustful of adults – he was told immunisation shots he was given at a young age would not hurt, when of course they did – Sammy sets out on foot uncertain of how he will complete the journey, but determined that he will. Along the way his distrust of adults is reinforced thanks to encounters with those who seek to profit from him and due to his witnessing the cruelty humans can inflict upon one another.

But also along the way there are those who do seek nothing more than to help him. One of these is a poacher and diamond trader – the kind of person you’d believe only to willing to take advantage of a young boy alone in the world. But it is compassion that rules this man’s heart (played in the film by Edward G. Robinson), and he takes the boy under his wing, helping him to heal from his emotional wounds …

Join Gyro Muggins for more of the adventure.

Tuesday, August 1st 19:00: What’s Cookin’ in Miss Trolley’s Kitchen

Inspired by Jenni Ferrari-Adler’s Alone in the Kitchen with an Eggplant: Confessions of Cooking for One and Dining Alone, she invites you to bring your favorite guilty pleasure recipes to share.

Wednesday, August 2nd 19:00: Secrets of the Divine Ya-Ya Sisterhood

Caledonia Skytower reads Rebecca Wells’ 2014 tale.

When Siddalee Walker, oldest daughter of Vivi Abbott Walker, Ya-Ya extraordinaire, is interviewed in the New York Times about a hit play she’s directed, her mother gets described as a “tap-dancing child abuser.”

Enraged, Vivi disowns Sidda. Devastated, Sidda begs forgiveness, and postpones her upcoming wedding. All looks bleak until the Ya-Yas step in and convince Vivi to send Sidda a scrapbook of their girlhood mementos, called “Divine Secrets of the Ya-Ya Sisterhood.”

As Sidda struggles to analyze her mother, she comes face to face with the tangled beauty of imperfect love, and the fact that forgiveness, more than understanding, is often what the heart longs for.

Also presented in Kitely (hop://grid.kitely.com:8002/Seanchai/108/609/1528).

Thursday, August 3rd 19:00: Brea’s Tale from The World of Feyland (Part 2)

With Shandon Loring. Also presented in Kitely (hop://grid.kitely.com:8002/Seanchai/108/609/1528).

 


Please check with the Seanchai Library’s blog for updates and for additions or changes to the week’s schedule.

The featured charity for May through July is Alex’s Lemonade Stand Foundation, raising awareness of childhood cancer causes and funds for research into new treatments and cures.

SL project updates 30/3: TPV Developer meeting

Follow Your Bliss, Sea Foam; Inara Pey, July 2017, on Flickr Follow Your Blissblog post

The majority of the notes in this update are taken from the TPV Developer meeting held on Friday, July 28th 2017. The video of that meeting is embedded at the end of this update, my thanks as always to North for recording and providing it. Timestamps in the text below will open the video in a separate window at the relevant point for those wishing to listen to the discussions.

Server Deployments Week #30 – Recap

Please refer to the deployment notice for the week for latest updates and news.

Main (SLS) Channel

There was no deployment / re-start of the Main (SLS) channel on Tuesday, July 25th, the Main (SLS), which remains on server maintenance package #17.07.11.327548. This update included a fix to allow DJ boards to work, however, any scripts which have not been updated to meet the new requirements may not work. for details, please refer to this forum thread.

RC  Channels

The deployment to the RC channels did not go as planned, after it was discovered the release had a creeping crash bug that could not be reproduced on Aditi, but would be a bad experience for all regions on the RCs. A roll-back was therefore performed, leaving all three RCs on the same server maintenance package as the Main (SLS) channel (#17.07.11.327548).

SL Viewer

[0:10-3:33] The Maintenance RC viewer updated to version 5.0.7.327940 on Friday, July 28th. This update includes two crash fixes, and an update for a pull request fix, which Oz has asked third-party viewers to include as soon as possible. Essentially, some of the very low-level code in the log-in process has a very aggressive approach to retries if it encounters log in delays, and this needs rectifying.

This only became apparent when a main network cable in the Lab’s data centre was severed (by a backhoe!). This shifted log-in attempts to an alternative network connection where the combination of high user numbers and this aggressive retry loop in the code resulted in what was essentially a denial of service attack which overwhelmed the log-in servers. Given the depth of the code in the viewer, it is believed it is present in the vast majority (if not all) viewers. This also means the Maintenance viewer will get promoted relatively soon.

[3:59-5:16] The Alex Ivy 64-bit viewer still has an elevated crash rate and the Lab is making changes to obtain better data on the crashes. The 32-bit version of the viewer in particular is suffering “really high” crash rates.

The remaining viewers in the pipelines remain unchanged:

Web Property, Attachments and ToS Issues

[5:48-7:01] Some users have been experiencing some or all of the following issues during the week:

  • Inability to access various LL web properties (e.g. their own dashboard, the JIRA system, etc). As of the TPV Developer meeting, all web services were believed to be back up and running, although the Lab weren’t sure as a to the cause of the issues.
  • Attachment failures – either on attach or with scripts. These are still being investigated, and a definitive cause has not yet been found.
  • The Terms of Service update, which officially comes into force on Monday, July 31st but which currently requires acceptance by users, has been causing log-in issues for some. Again, the cause isn’t as yet known.

Other Items

Parcel Sounds

[7:55-13:12] There is a discussion on parcel sounds (from objects and avatars). In short: parcel sounds can be restricted from within a parcel going out, but not for sounds from other parcels coming in. As parcel privacy is two-way, this has caused some confusion for some users. The Lab is hesitant to change the scope of the setting (e.g. make it apply to both sounds leaving and entering a parcel), they are possibly amenable to changing the setting to sounds are restricted to parcels by default, or receiving a code contribution / feature request to separately stop sounds entering a parcel.

Sansar Public Beta

[17:58-18:50] During the meeting, Oz Linden indicated that the Sansar public Creator Beta will be launching on Monday, July 31st / during the week commencing Monday, July 31st.

However, during the week of July 24th through 28th, the Lab hosted a series of meetings involving staff, those of us fortunate enough to be in Sansar and creators and bloggers from Second Life who have not been a part of the Creator Preview in which it was indicated the company wasn’t ready to provide a date for the public Beta, other than it being “soon”.

We’ll obviously find out what is happening on Monday, but either way, I’ll have at least one article on Sansar and Second Life coming out quite soon which will delve into the meat of the meetings – so to speak!

Lab’s Second Life Development Summit

[18:00-18:42] Week 31 (commencing Monday, July 31st) marks the next Second Life summit in which Lab staff directly involved in running and maintaining SL (developer, product team, operations, etc), get together to plan out the next several months of work and projects for the platform.

In Brief

[19:51-20:36Further Estate Tool Improvements: the work to improve the Region / Estate floater in the viewer to make it easier to manage ban lists, etc., is still in-hand at the Lab, it’s just been delayed due to other work being carried out / completed.

[21:26-22:57] Premium “Goodies”: Grumpity Linden indicated there are some “awesome goodies” in the pipeline for Premium members, which sparked a lot of text-based suggestions.

[22:57-25:46] Group notices being dropped: there are issues around group notices being received by users in certain groups. The Lab has made adjustments to handling the UDP packets which handle group notices to try to improve things, but the issue of dropped notices is hard to reproduce, and therefore hard to diagnose and fix.

[26:51] Place Pages: have been updated to include events.

 

Second Life: updates to some purchase notifications

On Friday, July 28th, the Lab blogged about some changes to some purchase notifications. The blog post making the announcement reads in full:

As you may notice, to fulfil legal obligations, we have added a notification in some places when making purchases that clarifies which legal entity you are transacting with, depending on the country associated with your payment method. Tilia Inc. and Tilia Branch UK Ltd are wholly owned subsidiaries of Linden Research, Inc, and this does not affect how you contact or receive support.

We wanted to clarify this to hopefully help those who may have encountered this and were wondering why they saw some updated notifications.

The Marketplace is one of the areas where these changes are visible. When paying the Second Life Cashier (cashier page), a notification is displayed at the foot of the invoice column:

New purchase notification on the Marketplace Cashier page

This change also matches recent updates to the Linden Lab Terms of Service which now reference Tilia Inc and Tilia Branch, as which come into effect on Monday, July 31st (and you may already have been asked to accept the new ToS when logging into Second Life or one of the Lab’s web properties).