PDA

View Full Version here: : Don't forget your leap-second tomorrow!


ngcles
31-12-2008, 01:03 PM
Hi All,

Tomorrow, in Australia (and worldwide at different local times) we all get an extra second to live -- don't waste it.

The second leap-second of the decade will be added tomorrow just before 11am (EDST) -- or 00:00 UTC.

The addition of the odd leap-second now and then is necessary because of the very gradual slowing of the Earth's rotation. This slowing of the Earth's rotation is due to the approach of Planet X (Nibiru) (Sorry to the moderators -- just couldn't resist that one :P:P:P).

But seriously, the cause of the slowing of the Earth's rotation is basically due to the ocean tides. The ocean tides are basically due to the gravitational attraction of our Moon.

The tides washing around the continents and in and out of bays and estuaries creates a gentle brake on the Earth's rotation very, very gradually slowing it down.

Because the total angular momentum of the Earth-Moon system must remain constant (the laws of physics aren't "guidelines" mate), the apparent loss of the Earth's rotational energy is transferred to the Moon -- increasing the Moon's orbital velocity which in turn causes it to slowly recede from Earth.

Unfortunately, a few silly sausages are saying that the second is to be added tonight before 12mn -- this is incorrect. The leap second will be inserted just before 00:00 UTC (Co-ordinated Univeral Time) (similar to the old GMT) or just before 11am EDST.

Ordinarily tomorrow it would go something like 10:59.57 -- 10:59.58 -- 10:59.59 -- 11:00.00.

Instead, it will go 10:59.57 -- 10:59.58 -- 10:59.59 -- 10:59.60 -- 11:00.00.

Enjoy that extra second! Happy New Year and welcome to the 2009 IYA!


Best,

Les D

andrewk_82
31-12-2008, 01:06 PM
What to do with all that spare time? :shrug:

jungle11
31-12-2008, 01:27 PM
I might pick up a book....tick....and put it down again:P

gary
31-12-2008, 01:31 PM
Thanks Les,

I've come up with a detailed agenda as to how I will be using that extra second. :thumbsup:

If you have a short wave receiver, it is amusing to listen to WWV in
Colorado and WWVH in Hawaii for the additional second and I have
done this on occasion.

See
http://tf.nist.gov/stations/wwv.html
http://tf.nist.gov/stations/wwvh.htm

There has been some professional discussion going on for some time about whether
leap seconds in the future will be abandoned.

TAI, which is an atomic clock time, differs from UTC by the number of leap seconds
inserted since 1960 January 1.0, so come 11:00 AEDT tomorrow, TAI will be
34 seconds ahead of UTC.

For some astronomical calculations, this is significant difference and one can't
always blindly use UTC without taking the accumulated leap seconds into account.

Happy New Year!

Best Regards

Gary Kopff
Managing Director
Wildcard Innovations Pty. Ltd.
20 Kilmory Place, Mount Kuring-Gai
NSW. 2080. Australia
Phone +61-2-9457-9049
Fax +61-2-9457-9593
sales@wildcard-innovations.com.au
http://www.wildcard-innovations.com.au

Jen
01-01-2009, 05:12 AM
Cool i get to fit in one more can before i go to bed :lol::lol::lol:
:D

Jen
01-01-2009, 05:13 AM
:lol::lol::lol::lol:

Ric
01-01-2009, 11:44 AM
I missed it and I had so many things planned.;) :lol:

Cheers

AlexN
01-01-2009, 01:50 PM
I used my second well... During the leap second, I flicked the switch to power up my mount/cameras/laptop in preparation for imaging! :D

Yay!

renormalised
01-01-2009, 02:09 PM
Yep....I "leaped" my second, and....did nothing:P:D

Kindred Spirit
02-01-2009, 03:28 PM
I caught up on sleep! A "Nanno" nap!

renormalised
02-01-2009, 03:34 PM
Welcome to IIS, Luise:D

I like your avatar....an "astronochino":P:D

Kindred Spirit
02-01-2009, 03:41 PM
Thanks, yes- a cosmic coffee!

Kindred Spirit
04-01-2009, 12:30 AM
Have added a "mug" shot to profile in case the cup and saucer was misleading!