Search found 632 matches

by keithl
Tue Jul 03, 2018 3:36 am UTC
Forum: Individual XKCD Comic Threads
Topic: 2014: "JWST Delays"
Replies: 19
Views: 1112

Re: 2014: "JWST Delays"

I am more hopeful for the Large Synoptic Survey Telescope, nearing completion on Cerro Pachón ridge in Chile. LSST is a point and shoot: fast slewin and stabilizing, then collecting two images in ten seconds with an 8.4 meter primary mirror and a 3.2 gigapixel imager the size of an SUV. It will gene...
by keithl
Mon Jul 02, 2018 6:54 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 2014: "JWST Delays"
Replies: 19
Views: 1112

Re: 2014: "JWST Delays"

Late 2026? I'll be fifty ... or dead ... or both. I'm a generation older than you - and don't plan on being dead. Suspended animation, maybe. If the world survives that long ... I hope a competent data jockey will get a copy of the existing raw data from the Wide Field Infrared Survey Explorer (WIS...
by keithl
Fri Jun 29, 2018 12:04 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 2012: "Thorough Analysis"
Replies: 15
Views: 1298

Re: 2012: "Thorough Analysis"

A mere 100 page treatise? The "Time" thread is much longer than that. This thread can be hijacked, expanded, and turned into that treatise. Get researching, folks, and sign your work; 15 pages merely to list all the author's names. Then we find a suitable ejournal for the result. And if on...
by keithl
Thu Jun 14, 2018 5:36 am UTC
Forum: Individual XKCD Comic Threads
Topic: 2006: "Customer Rewards"
Replies: 39
Views: 2203

Re: 2006: "Customer Rewards"

Is there a reason this thread title is incorrect? Title from the last comic bleeding into this one, or something? Now where are my rewards?? Second time I've miscopied the title. Is there an easier way to do this right than opening four windows, (page, page source, example template, post reply wind...
by keithl
Thu Jun 07, 2018 6:29 am UTC
Forum: Individual XKCD Comic Threads
Topic: 2003: "Presidential Succession"
Replies: 65
Views: 3755

Re: 2003: "Presidential Succession"

My father-in-law Charlie Phelps is a pretty sharp guy. He turns 100 this month. He should be on the list, and everyone under 100 taken off it. OTOH, if we raise the age requirement to 110, we will probably get our first female president. Probably lots of them in quick succession, because they die li...
by keithl
Mon Jun 04, 2018 8:01 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 2002: "LeBron James and Stephen Curry"
Replies: 43
Views: 2820

Re: 2002: "LeBron James and Stephen Curry"

There is clearly no comparison. Stephen Curry, professor of structural biology at Imperial College, has 11435 citations, according to Google Scholar. LeBron James has one, for a television appearance. James will never get tenure at this rate.
by keithl
Sat Jun 02, 2018 7:46 am UTC
Forum: What If?
Topic: What-If 0157: "Earth-Moon Fire Pole"
Replies: 27
Views: 6700

Re: What-If 0157: "Earth-Moon Fire Pole"

Given a safety factor of three, a Xylon Phobos tether to Mars upper atmosphere would need to mass about 640 times as much as the payload/elevator car. ... An interesting pair of tethers would be a ~940 km ascending from Phobos and a ~2940 km tether descending from Deimos. Interesting blog! Sadly, X...
by keithl
Thu May 24, 2018 2:18 am UTC
Forum: What If?
Topic: What-If 0157: "Earth-Moon Fire Pole"
Replies: 27
Views: 6700

Re: What-If 0157: "Earth-Moon Fire Pole"

If you ever do find yourself descending a long pole/tether/rope to the Earth. I suggest you use some apparatus in addition to your spacesuit: a couple of wheels clamped around the pole, a generator, a high power tungsten-filament searchlight, and a compact "greenhouse tank" of very fast gr...
by keithl
Tue May 22, 2018 1:57 am UTC
Forum: What If?
Topic: What-If 0157: "Earth-Moon Fire Pole"
Replies: 27
Views: 6700

What-If 0157: "Earth-Moon Fire Pole"

Earth-Moon FIre Pole WOW! A new What-If! And it's about something I pretend to understand! Randall posits a space elevator ("fire pole") hanging to the Earth from our Moon, and describes many things that can go wrong (even with an unobtainium "pole"). However, there's a fix for ...
by keithl
Wed May 16, 2018 5:08 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1994: "Repairs"
Replies: 29
Views: 4093

Re: 1994: "Repairs"

For the truly obsessed (like me), the Y axis goes much further down . It involves: buying repair parts, and breaking those too buying some wrong repair parts, and failing to resell those on ebay breaking tools ruining carpets and floors filling house with toxic smoke serious injury killing pets jail...
by keithl
Tue Mar 20, 2018 12:34 am UTC
Forum: Individual XKCD Comic Threads
Topic: 1969: "Not Available"
Replies: 38
Views: 5079

Re: 1969: "Not Available"

Please help. I'm from Canada. I tried opening the comic with an US Proxy, and it still shows "This content is not available in this country". Try a proxy in Kazakhstan. The content is available there. The proxies there are DNS poisoned to go to a malware host instead. You need to use eith...
by keithl
Mon Mar 19, 2018 10:12 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1969: "Not Available"
Replies: 38
Views: 5079

Re: 1969: "Not Available"

jeanrenaud wrote:Please help. I'm from Canada. I tried opening the comic with an US Proxy, and it still shows "This content is not available in this country".

Try a proxy in Kazakhstan. The content is available there.
by keithl
Mon Mar 19, 2018 8:51 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1969: "Not Available"
Replies: 38
Views: 5079

Re: 1969: "Not Available"

I just wasted 10 minutes relearning how to put an ErrorDocument stanza in /etc/httpd/conf/httpd.conf on my server. http://keithl.com/x ... where x => any of a semi-infinite number of pages that I have not implemented. The downside is that the webspiders will hammer my site with requests for every po...
by keithl
Sat Mar 03, 2018 6:25 am UTC
Forum: Individual XKCD Comic Threads
Topic: 1962: “Generations”
Replies: 31
Views: 4473

Re: 1962: “Generations”

Sigh. I was looking forward to "... to 1865, Spontaneous Generation".
by keithl
Fri Feb 09, 2018 7:08 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1953: "The History of Unicode"
Replies: 60
Views: 7747

Re: 1953: "The History of Unicode"

In June 2017: 136,755 unicode symbols, up from 128,237 in 2016. At a linear rate of expansion, there will be more than 8 trillion unicode symbols a billion years from now, as the Sun heats the Earth beyond survivability. In that same time, the round-trip speed-of-light communication sphere will have...
by keithl
Wed Feb 07, 2018 6:13 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1952: "Backpack Decisions"
Replies: 37
Views: 4442

Re: 1952: "Backpack Decisions"

Why are most backpacks black? I would like something very much like my ancient Targus (durable, lots of pockets, black :( ) in yellow or orange with wide scotchlite strips. I walk outside at night, and I want to outshine a driver's dodopaddle (er, "smartphone") screen. Yes, I have a firema...
by keithl
Mon Feb 05, 2018 6:59 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1951: "Super Bowl Watch Party"
Replies: 23
Views: 4530

Re: 1951: "Super Bowl Watch Party"

Years ago, I was in San Jose on the day of the Super Bowl, and went on a hike in the hills with two dozen geeks. Our leader, Brad T., had jury-rigged a digital video recorder (before there were commercial products that did this) and was capturing the whole show on hard disk. But we weren't intereste...
by keithl
Wed Jan 24, 2018 6:32 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1946: "Hawaii"
Replies: 28
Views: 3946

Re: 1946: "Hawaii"

I'm surprised that in 2018, the "something we know" part of the security triad is still a string of ascii characters,which "ought to" change frequently and be different on every device. The problem isn't that users are stupid, it is that the inmates are running the asylum . The &...
by keithl
Fri Jan 19, 2018 7:26 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1944: "The End of the Rainbow"
Replies: 48
Views: 5475

Re: 1944: "The End of the Rainbow"

Million, billion, milliard, short scale, long scale ... feh. Use scientific notation, with e/E separating the exponent so we don't need to use superscripts. Not as difficult as lakh ( 1e5 or 100,000 ) and crore ( 1e7 or 100,00,000 ) common in India and south Asia; and yes, they do write the commas i...
by keithl
Fri Jan 19, 2018 7:04 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1944: "The End of the Rainbow"
Replies: 48
Views: 5475

Re: 1944: "The End of the Rainbow"

I found the gold fraction of the Sun in Anders and Ebihara, "Solar-system abundances of the elements", Geochimica et Cosmochimica Acta, 1982. That compares relative counts of atoms, and lumps deuterium and tritium in with hydrogen, so my 1e18 tonne estimate is imprecise, assuming H = 1.0 a...
by keithl
Fri Jan 19, 2018 7:42 am UTC
Forum: Individual XKCD Comic Threads
Topic: 1944: "The End of the Rainbow"
Replies: 48
Views: 5475

Re: 1944: "The End of the Rainbow"

A sextillion tons of gold. You could bankrupt every country on Earth a million times over by dumping that amount into the economy. A mere quintillion (1e18) tonnes - gold comprises about 5e-10 of the Sun by mass, and the mass of the Sun is 2e30 kilograms, thus the mass of gold is 1e21 kg, or 1e18 t...
by keithl
Fri Dec 29, 2017 9:11 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1935: "2018"
Replies: 66
Views: 6513

Re: 1935: "2018"

2018 is not divisible by ANY of the first 49 Mersenne primes. But how about the larger ones? We will probably have to try all of them, just to make sure that 2018 is cryptologically secure.
by keithl
Fri Dec 01, 2017 9:00 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1923: "Felsius"
Replies: 78
Views: 7125

Re: 1923: "Felsius"

Melting point and boiling point of ... water? Those temperatures are only "standard" at 101 kPascal (one "standard" atmosphere of dry nitrogen/oxygen). At very high or very low pressures, where 99.99% of the water in the solar system can be found, the temperatures are different. ...
by keithl
Fri Dec 01, 2017 8:46 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1923: "Felsius"
Replies: 78
Views: 7125

Re: 1923: "Felsius"

Planck units. The Planck temperature is 1.4168e32K, also known as an "absolute hotness" of 1.0. That way, if anyone asks you the temperature, you can say "close to zero" and be right every time - even if you are at the core of an exploding supernova. Added note: It is about 2 mic...
by keithl
Wed Nov 15, 2017 8:53 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1916: "Temperature Preferences"
Replies: 82
Views: 8693

Re: 1916: "Temperature Preferences"

... Minnesotans are tough. Or dumb. Both, really. How did anyone get tricked into living here in the first place? Anecdotally, by telling new immigrants that it lies at the same latitudes as places like Venice and Paris... Two of my great-grandparents were "probably" imported from Finland...
by keithl
Wed Nov 15, 2017 8:02 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1916: "Temperature Preferences"
Replies: 82
Views: 8693

Re: 1916: "Temperature Preferences"

The Moon should be on this chart; equatorial surface temperatures range from 127C to -173C over the one month "day". On the chart, way beyond the lower right, somewhere near the middle button of your right-hand-side mouse. Fortunately for visitors, it is a very dry heat, with no snowstorms...
by keithl
Mon Nov 13, 2017 6:56 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1915: "Nightmare Email Feature"
Replies: 20
Views: 3289

Re: 1915: "Nightmare Email Feature"

Longest delayed email reply? That's gotta be "What Hath God Wrought", the first long distance telegraph message from Washington DC to Baltimore in 1844. They have yet to receive a satisfactory reply. The reply I would send would be so controversial that this thread would run longer than &q...
by keithl
Fri Oct 20, 2017 5:53 am UTC
Forum: Individual XKCD Comic Threads
Topic: 1905: "Cast Iron Pan"
Replies: 108
Views: 11314

Re: 1905: Cast Iron Pan

I used to filings-season my cast iron pans at the poles, but the magnetic field is too strong there; the residual magnetism in the pan ruined my best dishes. Now ESA launches them out of the Guiana Space Center for me. The field at 5 degrees north is still substantial, but a high parabolic trajector...
by keithl
Mon Oct 09, 2017 8:45 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1900: "Jet Lag"
Replies: 29
Views: 4066

Re: 1900: "Jet Lag"

I prefer random maritime disasters to scheduled maritime disasters, though the latter can be easier to avoid.
by keithl
Mon Oct 02, 2017 11:44 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1897: "Self Driving"
Replies: 57
Views: 8654

Re: 1897: "Self Driving"

Pssshht, pliers are so pro-ish noob. The real noobs strip wires with a pair of scissors or their teeth. Blimey, I'd forgotten about teeth. That was my preferred method for years. Did you stop when you were down to two teeth, or could you strip wire with the jagged remaining single tooth? edit: Seco...
by keithl
Mon Oct 02, 2017 4:52 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1897: "Self Driving"
Replies: 57
Views: 8654

Re: 1897: "Self Driving"

Self-driving cars? That's nothing. Microsoft just invented the self-flattening pedestrian. Shaped-charge exploding batteries in the Windows phone, ignited when a Google car passes closely. The phone appears undamaged. The results look just like vehicular homicide. See you in court, Page and Brin!
by keithl
Fri Sep 01, 2017 4:49 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1884: "Ringer Volume/Media Volume"
Replies: 38
Views: 6199

Re: 1884: "Ringer Volume/Media Volume"

Is it just me or does it seem that Google engineers just don't care about sane audio controls? The controls work great for Google's paying customers, the companies that pay to bombard you with advertisements. You (and the hapless people around you) are the product that Google delivers to advertiser...
by keithl
Wed Aug 23, 2017 4:02 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1880: "Eclipse Review"
Replies: 51
Views: 6546

Re: 1880: "Eclipse Review"

I watched it with 30 friends in Idaho Falls. Have you ever heard the rumble of a whole city cheering? Punctuated with police sirens; the cops were cheering, too. The familiar Sun is replaced with a strange new object in the sky: a vast corona. Venus is brighter than you have EVER seen it, seemingly ...
by keithl
Wed Aug 23, 2017 3:45 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1880: "Eclipse Review"
Replies: 51
Views: 6546

Re: 1880: "Eclipse Review"

Predicting supernovas How predictable is a supernova? I know that we can't currently predict them from the Earth, but if we were to send probes to a distant star, could those probes tell us when it was going to go supernova? The neutrino flux from a supernova goes off the charts in the hours before...
by keithl
Fri Jul 28, 2017 6:26 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1868: "Eclipse Flights"
Replies: 31
Views: 4465

Re: 1868: "Eclipse Flights"

There is no abrupt edge of a shadow as depicted. The eclipse begins an hour before, with the blockage of the Sun increasing towards totality, then decreasing for an hour after. In a vastly broader swath to the north or south of the path of totality, where the Moon "misses" the Sun a bit, ...
by keithl
Wed Jul 26, 2017 7:07 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1868: "Eclipse Flights"
Replies: 31
Views: 4465

Re: 1868: "Eclipse Flights"

Er ... uh ... There is no abrupt edge of a shadow as depicted. The eclipse begins an hour before, with the blockage of the Sun increasing towards totality, then decreasing for an hour after. In a vastly broader swath to the north or south of the path of totality, where the Moon "misses" th...
by keithl
Mon Apr 17, 2017 3:26 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1825: "7 Eleven"
Replies: 85
Views: 18467

Re: 1825: "7 Eleven"

They need 37 minutes per day to replace all the freeze dried and vacuum dessicated fruits and vegetables.

Oh, wait. 7/11 doesn't have any fruits and vegetables. Maybe they can sell silica gel packs instead. Yum!
by keithl
Fri Mar 31, 2017 9:41 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1818: "Rayleigh Scattering"
Replies: 99
Views: 20424

Re: 1818: "Rayleigh Scattering"

Regarding why plants and chlorophyll are green (ultimate, not proximate cause): Plants use the "green" pigment chlorophyll to process light because the first eukaryotic cells with chloroplasts evolved in the ocean, at depths where green light does not penetrate. Broader spectrum pigments m...
by keithl
Mon Mar 20, 2017 6:20 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1813: "Vomiting Emoji"
Replies: 45
Views: 9959

Re: 1813: "Vomiting Emoji"

Re: xkcd cartoons about emoji and vomiting ...
Image
by keithl
Wed Feb 15, 2017 6:53 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 1799: "Bad Map Projection: Time Zones"
Replies: 70
Views: 11829

Re: 1799: "Bad Map Projection: Time Zones"

Greenland is stretched funny, probably because they get so little sun that its position in the sky (or below the southern horizon) has no bearing (ahem) on their schedules, while economic dealings with Europe do. Reforming this mess provides a great opportunity for regional defense. Greenlanders can...

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