Kevin's Watch

Posted: **Sat Jun 20, 2015 7:12 pm**

sgt.null wrote:some mod should clean this thread up.

Some mod might like things messy...

Posted: **Sat Jun 20, 2015 9:15 pm**

Vraith wrote:Some mod might like things messy...

That just means you're doing it right.

Posted: **Wed Jun 24, 2015 12:05 pm**

Trying to hammer sum edycashun into you guys is like to carry water in a frickin' culonder ......err.....colindor,calendor - Oh forget it!

Posted: **Fri Jun 26, 2015 4:23 am**

horses for courses
the market forces...

Posted: **Fri Jun 26, 2015 8:06 am**

Homework for tonight. If the world's rotational speed slows by half a second a year (I believe this figure is about correct), in what year will the earth cease to rotate, and as a corollary, will we have to spend our time migrating in an ever continuous circular path around the earth in order to survive!

Posted: **Fri Jun 26, 2015 1:26 pm**

365.2425 * 24 * 3600 = 31, 556, 952 seconds so if the rotational speed is dropping by 0.5 s/yr then 63, 113, 904 years.

I would tend to disagree with that assessment because if it were accurate then the planet would already have slowed down so much that we wouldn't have such things as "day" and "night".

Posted: **Fri Jun 26, 2015 1:31 pm**

Scientists have reliable data on the Earth's rotational speed, based on observations of the sun's position in the sky during solar eclipses, going back some 2,500 years. Although the rotational rate hasn't declined smoothly, over that period the average day has grown longer by between 15 millionths and 25 millionths of a second every year. Even at the faster rate, it will take 140 million years before the Earth's rotation slows enough to necessitate a 25-hour day.

Posted: **Fri Jun 26, 2015 1:49 pm**

That sounds more accurate--.0000015 s/yr to .0000025 s/yr. The core of the planet rotates at a different speed than the mantle and crust, which is probably why the rate of slowing isn't constant.

Posted: **Fri Jun 26, 2015 2:45 pm**

Hashi Lebwohl wrote:The core of the planet rotates at a different speed than the mantle and crust, which is probably why the rate of slowing isn't constant.

The greater factor is tidal pull from the moon. Earth rotation is literally dragging the moon along with it.

Yes it is, due to a transfer of Earth's rotational momentum to the Moon's orbital momentum as tidal friction slows the Earth's rotation. That increase in the Moon's speed is causing it to slowly recede from Earth (about 4 cm per year), increasing its orbital period and the length of a month as well.

To picture what is happening, imagine yourself riding a bicycle on a track built around a Merry-go-Round. You are riding in the same direction that it is turning. If you have a lasso and rope one of the horses, you would gain speed and the Merry-Go-Round would lose some. In this analogy, you and your bike represent the Moon, the Merry-Go-Round is the rotating Earth, and your lasso is gravity. In orbital mechanics, a gain in speed results in a higher orbit.

Posted: **Wed Jul 01, 2015 3:57 pm**

Wow - the bastard! I used the figure in good faith as provided by Bavid Ewing Duncan in his "International Bestseller" which acording to The Observer "..sparkles. Gripping , expansive, scholarly and indispensable".

I quote

Average decrease in the year due to a gradual slowing of the earth's rotation; 1/2 second per century.

Time that the year has slowed since AD 1; 10 seconds.

heh heh heh

Yes, well err....

Posted: **Wed Jul 01, 2015 9:04 pm**

BTW, we seemed to have survived June 30's leap second adjustment with minimal outages. The last couple were pretty bad.

In case anyone is wondering, the leap second bug occurs in older versions of UNIX. When a leap second adjustment is detected, the UNIX operating system prints a message to it's log file to say 'leap second adjustment is detected' or something like that. However, it does this at the wrong place in the code, causing a deadlock (the computer locks up, everything stops). When the deadlock is detected by another part of the operating system, it "panics". A panic is when the operating system displays a diagnostic message on it's monitor. In this case, it would say something like "Deadlock detected." It then waits for a user to read the message, and when the user presses ENTER , the computer reboots. (So it's like Blue Screen on Windows.) You can configure it to reboot automatically, but most people never have done that.

It's a pretty stupid bug. All because someone wanted to print a message. But it goes pear shaped pretty fast. Computers all across the world are sitting there saying "Deadlock Detected, press ENTER to reboot", waiting for a human operator.

Posted: **Thu Jul 02, 2015 3:53 pm**

wayfriend wrote:
It's a pretty stupid bug. All because someone wanted to print a message. But it goes pear shaped pretty fast. Computers all across the world are sitting there saying "Deadlock Detected, press ENTER to reboot", waiting for a human operator.

Is that a real thing? Or are you playing the "What are the REAL lyrics to twinkle twinkle little star" game again?

If it's real, it is stupid...but also kinda funny.

Posted: **Thu Jul 02, 2015 5:52 pm**

Vraith wrote:If it's real, it is stupid...but also kinda funny.

Real. But simplified. [link] [link]

Not as bad as the 1990 collapse of the entire phone system due to a one-line programming mistake involving a [now infamous] "break" statement. [link]

But it's amazing how one little thing can destroy the world.

Posted: **Fri Jul 03, 2015 11:04 pm**

Did I hear that the NY sock exchange crashed a week or two ago because a guy spilled a can of coke on his keyboard?

Posted: **Sat Jul 04, 2015 2:07 pm**

peter wrote:Did I hear that the NY sock exchange crashed a week or two ago because a guy spilled a can of coke on his keyboard?

Heh...I hadn't heard that one.
Good thing I was happy with the socks I was wearing that day.

[you are like, the most funnest typo-hero on the Watch--not that you make the most, or even more than me, but you do it in the bestest places]

But it is true that little things like that [mostly human caused, but some code-related] can have large effects like that.
[[I think most of the markets have tech in place now that does that on purpose---shuts down trading in a particular stock, or particular market, [or even all the exchanges?? Not sure if anything THAT big is in place.] when certain kinds of movement are detected. ]]

Posted: **Sun Jul 05, 2015 10:32 pm**

I read it in pretty straight up may somewhere. Yes - good typo V. - You should see some of the ones that don't get by me; they always seem really apposite in a weird Freudian way!

Posted: **Wed Dec 16, 2015 6:21 pm**

Today in Earth Slowing Down news:

Climate change is a drag (on Earth), study says

It turns out that water melting off glaciers and moving away from the poles acts much like an ice skater's outstretched arms, making every rotation that much slower, said Jerry Mitrovica, a Harvard University professor of geophysics and lead author of the paper.

How much slower?

In Earth's case, one millisecond a day. That's a thousandth of a second. [link]

That's 0.1 seconds per century. Compared to 0.5 seconds per century due to the tidal effects of the moon. So significant, but not game-changing.

Posted: **Sun Jan 03, 2016 4:57 pm**

The day the Earth stops rotating will be long past the time the sun swells into a red giant and engulfs the Earth.

Be sure to put on your sunblock. SPF 5 trillion.

Posted: **Mon Jan 04, 2016 5:21 am**

This year is a leap year.

--A

Posted: **Tue Jan 05, 2016 8:32 am**

Avatar wrote:This year is a leap year.

--A

we can now properly celebrate Superman's birthday.

or did DC Comics change that too?

Kevin's Watch

Calanders and Leap years