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Submission + - A physical model for (some of) Tabby's Star's light dips. 2

RockDoctor writes: A fresh paper on Arxiv describes a model proposed to explain at least some of the light dips in "Tabby's Star" (Kepler Input Catalogue KIC 8462852). When the irregular light received from this star was recognised in 2015, nobody could come up with a credible explanation for the irregularity of the star's light dips, or their depth. Further studies suggest sustained dimming over the photographic observation epoch, further deepening the puzzle. This new paper proposes a model of a jet of material which leaves the star's surface, then casts off a plume described as "smoke plume" which is swept around in the stars orbit. The opaque jet and the less-opaque "smoke plume" then intersect with the light travelling towards us to generate an asymmetric dip in the star's light curve, as observed in the past.

Which is an interesting model. The big peculiarity is that the "smoke plume" orientation with respect to the material jet implies that the outer parts of this star's envelope is rotating faster than the inner part where the jet originates. Which would raise almost as many questions as the original discovery.

Definitely, this is a very peculiar system.

(PDF here ; NB, the paper does not appear to have been submitted to a journal, or peer-reviewed.)

Submission + - Cards Against Humanity are in a hole! ( 1

RockDoctor writes: Well-known enemies of Political Correctness "Cards Against Humanity" have moved on from sending people un-funny phrases on bits of card (which users then combine into hilarious, offfnsive, or hilariously offensive combinations) to their annual festive "thing". Having previously raised prices, delivered Lance Armstrong's missing testicle, and sent people bullshit, this year's comment on "Black Friday" is to dig a hole with user's contributions. And that's it. No more. Nothing will happen apart from an innocent piece of land will become a hole. An expensive hole. A hole into which users have willingly poured money instead of doing something useless.
So vote with your credit cards and get that hole dug. There are (at the time of this submission) 29 hours and 52 minutes to pour your money on top of the $30,400 already poured into this hole in the ground. No matter how much you pour in, you'll never get the hole to over flow, but don't let that stop you trying! (29h 43 minutes now, and $32,000.)

Submission + - The iron fist pokes out through the velet glove. 1

RockDoctor writes: Google are (allegedly) shutting down the Google Accounts of people indulging in a sales-tax [trick/ scam/ workaround — IANAmerican, so I'm not sure on the legal status of this], blocking them from access to photos, emails, contacts and the other detritus of a digital life. The Guardian adds : "Google has suspended the accounts of hundreds of people who took advantage of a loophole in US sales tax to make a small profit on Pixel phones.
The Google customers had all bought the phones from the company’s Project Fi mobile carrier, and had them shipped directly to a reseller in New Hampshire, a US state with no sales tax. In return, the reseller split the profit with the customers."

"One user reported that an account that hadn’t been used to purchase a Pixel was suspended, apparently because it was listed as a back-up address for an account that had."

People might ask, in a hurt tone of voice, "why are you doing this to me?" To which the obvious answer is "because we can, and you agreed to these (link to 3000 pages of text) terms and conditions, including our ability to do this."

Totally expected behaviour. The only question has been 'When?', never 'If?'

Submission + - All about life around an M-class star

RockDoctor writes: Arxiv has a review article on "The Habitability of Planets Orbiting M-dwarf Stars" (PDF). Although Star Trek had a minor smattering of "M-class planets" — a designation that tells one nothing of substance, "M-class star" is a much more meaningful designation of colour, with two size classes, the dwarfs and the red giants. M-class ("red") giants are not prospective for life — it's a short duration of the life of any star that gets into that state (most won't) and it ends badly for anything not made of tungsten carbide. M-class dwarfs, on the other hand "are our galaxy’s silent majority: they constitute 70% of the stars in the Milky Way and 40% of its stellar mass budget, yet not a single M dwarf is visible to the naked eye. They span nearly an order of magnitude in mass and two orders of magnitude in luminosity. [...] As a spectral class, M dwarfs span a larger range in mass than the next three spectral classes (F,G & K) combined." But probably the most important reason for paying attention to them is their persistence — an M-dwarf of 1/10 the mass of the Sun will burn for around 1000 times the time that the Sun does. No M-dwarf has ever turned into a red giant — there hasn't been enough time.

Therefore, if humanity ever meets an alien species, the odds of them coming from an M-dwarf are already high. If humanity ever meets an alien species that has been around a billion years longer than us and has technology we can't even dream of, then the odds of it coming from an M-dwarf are overwhelmingly high. Clearly, understanding these stars, and the influences of these stars range of properties on their planets and possible inhabitants (including our distant descendants) is a good idea. And this review article will keep you up to date for your next term paper. Or for keeping your SF magnum opus somewhere with a passing acquaintance with reality.

Submission + - Samsung are investigating the effects of the '7' fiasco on their brand.

RockDoctor writes: I routinely fill out for-pay surveys for a commercial survey company for an earning rate somewhat better than minimum wage.

I had one just now for Samsung, inestigating the effect on their brand's perception of the Note 7 battery fiasco. While I'm not particularly worried — the difficulties of high energy density devices have been known since the Chinese started putting fireworks in their robes and getting burned — it does show that Samsung are worried about the consequences. Contrary to what some of the more hysterical Apple fan-bois say.

Personally, I don't give a shit if $DEVICE$ is a bit thicker. My current $DEVICE$ (an S5) resides in a fold-over wallet which effectively doubles it's thickness, and to no-one's astonishment, it still fits in my pocket, AND it hasn't yet borked it's screen when I've dropped it.

Submission + - It doesn't look too good for Tatooine.

RockDoctor writes: Everyone who has paid even the most cursory of attention to the Star Wars films (I've seen at least two of them. Out of however many.) knows that the planet Tatooine orbits two stars in close binary orbits. But everyone who has paid even the most cursory of attention to astrophysics knows that the evolution of the stars is likely to have ... consequences ... for any planets in orbit around the system's centre of mass.

A paper published yesterday on Arxiv studies the known planets in Tatooine-like systems (PDF). The Kepler telescope has confirmed a number of planets around close binary star systems. So astrophysicists have studied the evolution of these systems.

It doesn't look good for Tatooine-like planets. Of the nine systems studied, five experienced "common-envelope stages" where gas is transferred from the lighter of the two stars to the heavier (which changes the evolutionary trajectory of both stars). This is not good — cataclysmic novae and X-ray outbursts are common outcomes. On the other hand, "two systems trigger a double-degenerate supernova explosion" — which doesn't sound like it'll be good for the sunburn either. Those planets which don't suffer "RUD", don't do much better, as the "common-envelope stage" and the resulting gas drag and close-approaches can lead to 10-fold increases in both orbital diameter and eccentricity. In as little as one planetary orbit. Double-plus ungood.

All in all, Tatooine-like planets would probably not be a place to put a long-term centre of government. So actually, Lucas wasn't far wrong.

Submission + - Crib-sheet for Gravitational Wave essays. (

RockDoctor writes: Those of you studying — be it astronomy, physics, or crochet — will probably have already faced the need to write a few thousand words and equations on the subject of gravitational waves (GW). So, if you hold the "popular science" opinion that Einstein predicted the existence of GW in 1916, then you might just want to read this review essay prepared by Nobel laureate George Smoot and two others. For the first 50 words of your essay, Smoot et al. trace the idea of GW back to "an article written by Henri Poincare entitled “Sur la dynamique d’ l’électron.” This work summarized his theory of relativity. The work proposed that gravity was transmitted through a wave that Poincaré called a gravitational wave (onde gravifique)" in Comptes Rendus. (OK, this journal title is in French, but not all of the articles are, this century. This article is though, so you'd better sharpen up your passe passif. The paper is available via the Bibliotheque National Francais here. And here is the necessary rant about the ridiculousness of not being able to type a C-cedilla due to Slashdot's inability to handle non-ASCII characters.).

Another 30 pages (including references) describes the "theoretical and experimental blunders, efforts towards their detection, and finally the subsequent successful discovery," including the inevitable bets and the occasional millionaire chucking a moderate amount of funding at this ridiculously wild field of study.

Submission + - How will we know a vehicle model is "driverless" (

RockDoctor writes: Some people differ, but having gone through dozens of (simulated) aircraft crashes as part of safety training for work, I hugely prefer to face backwards when travelling. Plane (no choice) train (choice) or automobile (rarely a choice), I prefer to be in a seat that will absorb my momentum from the start of an impact.
The "driverless car" will not be here until all people in the front row of the device face against the direction of travel. Anything less is a partial solution, waiting for a human to take over in a complex situation.
My wife can't travel facing backwards. So I take the risk of being killed by her flying body after I survive the crash. Joy, not.
People will learn to live with it.


Submission + - Continuing progress on "In Situ Resource Utilization" for space exploration. ( 2

RockDoctor writes: Many Slashdot readers will have heard of Robert Zubrin with his plans for launching self-contained rocket fuel plants to Mars to convert 1kg of hydrogen (supplied from Earth) to 18kg of oxygen/ methane to be used as rocket fuel to return explorers to Earth. This is an example of Utilizing (using) In Situ (already there) Resources (Mars' CO2 atmosphere) to reduce launch costs (masses) from Earth to achieve desired aims in space exploration at more affordable costs.

In 2013, the Journal of Aerospace Engineering ran a special volume on "In Situ Resource Utilization" with 20 papers on the subject. (These are paywalled, unless you know of tools like Sci-Hub to read the work paid for by your taxes.)

Yesterday, one of the editors of that special volume, Philip Metzger (a NASA planetary scientist specialising in the properties of Lunar soils) released a paper on Arxiv expanding on his contribution to that 2013 volume and detailing a roadmap for humanity to take gain control of the Solar System in order to solve problems on Earth. In the 2013 paper, Dr Metzger asserted (with working) that

bootstrapping can be achieved with as little as 12 t landed on the Moon during a period of about 20 years. [ I know it's Slashdot but RTFAFFS ! ...] The industry grows exponentially because of the free real estate, energy, and material resources of space. The mass of industrial assets at the end of bootstrapping will be 156 t with 60 humanoid robots or as high as 40,000 t. [...] Within another few decades with no further investment, it can have millions of times the industrial capacity of the United States. Modeling over wide parameter ranges indicates this is reasonable, but further analysis is needed.

The 2016 Arxiv paper produces some of the results of that further analysis, concentrating in particular on the need to develop a "water economy [..] to manufacture rocket propellant" from in situ resources on the Moon and later the asteroids.

The 2013 paper's abstract ends with one of the milder understatements in history.

"This industry promises to revolutionize the human condition."

Without doubt, Slashdot will contribute much heat and little light from typing hordes who haven't read either paper to dilute their ignorance, but analyses like this are not, as frequently described, the work of "space nutters" but realistic possibilities. Realistic until the author sees the fatal stumbling block to all such dreams :

"It will require a sustained commitment of several decades to complete."

— a level of dedication that humans have not shown themselves capable of for centuries, even for their highest achievement to date, war.

Submission + - Kepler releases catalogue of Habitable Zone exoplanet candidates.

RockDoctor writes: The Kepler consortium has released a catalogue of exoplanet candidates, filtered (according to various criteria) to include only those in their star's "habitable zones" ("HZ", where water could be sable as a liquid on the planet's surface). While there are inevitably plenty of caveats about the work, it does provide a list of potential targets for further study, and no doubt many of them are being followed up already. Planetary astronomers now have a "catalog[ue] of 104 candidates within the optimistic HZ and 20 candidates with radii less than two Earth radii within the conservative HZ". For those doing their astronomy homework assignments, there is a useful 2 page description of their HZ criteria.

The data is tabulated in the paper, but is keyed by KOI number, which users would need to cross-reference to the data on NASA's Exoplanet database.

As the authors say themselves, "The work described here is the product of efforts undertaken by the Kepler Habitable Zone Working Group," who might possibly know more about the subject than Joe Random Slashdotter. But that won't inhibit them from correcting the work without reading it.

Submission + - Second irregularly dimming star found. (

RockDoctor writes: Remember the screaming and welcoming of our Dyson-Sphere-Dwelling 1500 LY distant Overlords that accompanied the news that star KIC 8462852 was irregularly dimming on both short and longer timescales?

A second star with a similar light curve has been discovered and reported on ARXIV. With the euphonious names "EPIC 204278916" and "2MASS J16020757-2257467", the star is a young M1 (red) star, travelling as part of a group of stars which haven't had time to disperse from their place of formation. The age is estimated at 5 — 11 million years.

Analysis of 70+ days of data from the K2 mission epoch shows a rotation of 3.6 days, but a period of 25 days near the start of the observation epoch showed dips in intensity of up to 60% lasting for up to about a day each. Details are in the Arxiv paper linked to above, particularly figures 1 and 4.

If confirmed, this discovery changes the situation with interpreting the so-called "Tabby's Star". Firstly with a second object in the class, the odds of it representing a class of naturally occurring objects compared to a unique, unusual object is greatly increased. Secondly, the different celestial mechanical situations around the different stars allows a better estimate of plausible formation mechanisms. One potentially important point is that clumps of debris that could produce these dimmings seem to be quite large. "It is also important to note that the resulting size for the transiting and occulting clump would be quite large at with the clump being in the order of 1.5 times the radius of the Sun.

Sadly, this appears to be a new class of "dirty young planetary system." no alien Overlords, no screaming in the streets. Just business-like astronomy.

Submission + - Microsoft Bing uses Wikipedia (globally editable) data

RockDoctor writes: Though they're trying to minimise it, the recent relocation of Melbourne Australia to the ocean east of Japan in Microsoft's flagship mapping application is blamed on someone having flipped a sign in the latitude given for the city's Wikipedia page. Which may or may not be true. But the simple stupidity of using a globally-editable data source for feeding a mapping and navigation system is ... "awesome" is (for once) an appropriate word.

Well, it''s Bing, so at least no-one was actually using it.

Submission + - ESA and Tim Peake to rent out room on ISS on AirBnB

RockDoctor writes: After their successful deployment of the inflatable broom cupboard on the International Space Station, the ESA and Tim Peake are planning to rent it out on AirBnB.

No comment on when the road there will be improved — it's unsurfaced (and un-foundationed) for the last 100+ km — but the parking for your vehicles could easily be described as "spacy". Driving up there — particularly in a convertible car — is literally breathtaking. You'll feel all the pressures lifting from you.

I'm writing like an advertising agent. I'd better commit sepukku with an IBM mechanical keyboard.

Submission + - Progress reports on Plan-28, the project to (re-)build the world's 1st computer. (

RockDoctor writes: Many readers will be aware of the continuing project to (re-)build a version of an antique computer which not even Slashdot's venerable 3-digit UID greybeards have worked with. Between 1822 and 1847, Charles Babbage worked on a number of designs for general-purpose programmable computing engines some parts of which were built during his lifetime and after. Since 2011 a group under the name of "" have been working towards building a full version of the machine known as the Analytical Engine. (The group's name refers to the series of Babbage's plans which they are working to — versions 1 to 27 obviously having problems.) This week, they have released some updates on progress on their blog. Significant progress includes working on the machine's "internal microcode" (in today's terminology ; remember, this is a machine of brass cogs and punched cards!) ; archive work to bring the Science Museum's material into a releasable form (the material is already sanned, but the metadata is causing eyestrain) ; "One of the difficulties in understanding the designs is the need to reverse engineer logical function from mechanical drawings of mechanisms — this without textual explanation of purpose or intention. The original hope was that the notations, expressed in Babbage’s symbolic descriptive language [discussed here before]."

Progress is slow, but real. Last year marked the bicentennial of Ada Lovelace, who wrote programs for the Analytical Engine and it's predecessor, the Difference Engine, and whose position as "the world's first programmer" is celebrated in the name of the programming language Ada.

Submission + - Braindead staff at BurgerKing tricked into smashing windows - twice!

RockDoctor writes:

[A prank caller] tricked workers at a Minnesota Burger King into smashing the windows of the restaurant to keep it from exploding.

Which is pretty fucking funny — though it might cost the restaurant chain 10-30k$ and if anyone gets fired, it should be the manager who was caught by the prank and instructed his staff to start smashing the windows.

But it seems that there was another similar case "in Shawnee, Oklahoma, on Thursday night" ; and there are reports of other cases. So, Burger King's upper management should have been raising the alarm to their store-level management already. Or, perhaps, they might hire people with at least a trace of general science background.

This sounds more fun than pulling the wings off flies — and ethically is more defensible. Where is the printed Yellow Pages ...?

Hang on! When did Burger King get promoted from "sludge purveyor" to "restaurant." And how many restaurants are sueing them for defamation and reputational harm?

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