Time and Travel :)

So I know what latitude and longitude is, I just usually thought of it at as a position on google earth. Not necessarily linked with time zones. I have been learning all about time zones, its really cool. I love this stuff! During the time I'm not working I get to practice ETA problems for fun. The last one I did that was really tricky I got a 100! Heres how you figure them out!

Calculating ETA

What you need to know

1. Distance 
2. Speed 
3. GMT, Each locations ZD

GMT, Greenwich Mean Time

There are 25 integer World Time Zones from -12 through 0 (GMT) to +12. Each one is 15° of Longitude as measured East and West from the Prime Meridian of the World at Greenwich, England. 

Calculating Time 

To calculate the time it will take you use the equation D=ST, distance is represented by nautical miles, nm. Speed is represented by knots, kts. Time is represented by hours. 

Ex. Distance 7100 nm @ 23 kts, 

D=ST, so T=D/S, 

7100nm/ 23kts = 308.6956522 (this can now be converted to days, hours, and minutes) 

Calculating ZD 

Longitude ˚   = ZD (round to the nearest whole number) 

15˚

If the longitude is in the western hemisphere it is (+), if eastern hemisphere then   (-) 

For Example: Dallas, TX Longitude is 96.8039˚ W, so we divide 96.8039˚/ 15˚ = 6.45, rounded to 6. We are in the western hemisphere so it is a positive, +6. 

Converting to GMT

Greenwich Mean Time, The ZD in Greenwich is 0. To convert time to GMT you either add or subtract the ZD.If the ZD is + you add to convert to GMT and if negative you subtract. This was better explained to me by remembering the sun rises in the east and sets in the west and looking at time on the globe from that perspective. 

Ex. If it is 1200 in Dallas, what time is it GMT? 

We know Dallas is +6, so we add 6 to 1200, we then have 1800 GMT. :) Greenwich is ahead of us so thats why we add to convert to there time. 

IMPORTANT CONCEPTS

Great Circles

Great circle navigation is following the shortest route between two points on a sphere, the earth in this case. A great circle on any sphere is one that divides it in two equal halves: the equator, any longitudinal line through the poles, or any similar circle that has its center at the middle of the earth.

International Date Line

On the opposite side of the prime meridian, ZD 0, there is the international date line, located at 180˚, ZD +12,-12 on either side. When crossing the dateline from the west you automatically go to the next day. For example, if it is 1200 December 25th, once you cross your new time is 1200 December 26th. Time flies when you are having fun ;)! 

In other news, I have been on the rig for 10 days, so I still have a ways to go. I am running out of conditioner, so at least  I know next time what to bring more of! I have been getting some good workouts in, which is good! Im trying to get ready for this summer :) The gym is so awesome here. I will have to see if I can take some pictures to show you guys how cool it is. 

When I get home, I am so excited to go to the Museum and planetarium with Rachel. I haven’t been to the downtown museum of natural science in Houston, and I got a groupon for us to go.  We can spend some sister time together. Im so stoked about the planetarium, those are so much fun especially since its hard to see some good stars in Houston. Also I have been reading so much about stars I want to identify some :) I love love love love museums! When Schlumberger hired me, we got to have a catered dinner and a museum party, that included a knowledge based scavenger hunt, It was like the best night of my life! Except the team I was on got a question, that the answer was pluto, then we had to find pluto in the museum. The interesting part was this question was made pre pluto being kicked out as a planet, so they took pluto out of the museum planet section, and we couldn't find it. Since I was thinking this is probably not the place to get competitive and throw a fit I just let it go, but my teammates and I were pissed. We then got to make a parachute out of random supplies and had a contest to see who can build it and fly it to a target. Ours had the most lift time and was well designed, but did not hit the target :( . Creative Problem Solving is my S&*% !!! I get like high off of those kinds of activities! 



 The chicago field museum is the best one I have been to though so far. I love that city! 

Me and Sue, the biggest T REX ever!!!!!

Anyways, 

Love and Miss you all! 

Hill