February 15th, 2010
Dang, I have been a terrible blogger lately. Not one blog in a week. I will have to do a blog today and tomorrow to make up for it.
Some highlights of the past week. It can be summed up as “Hurry up and Wait”.
So out here sometimes there is no core to work on, and sometimes you can have core coming out of your ears a day later!
A week ago we had no core to work on. Just one day later we had enough core that we worked nonstop for 4 days. We had so much core to work on, that we did not finish before we had moved on to the next site! And a day after that move, we again had no core to work on and were waiting out another storm!
When last I wrote, we were heading offshore to avoid a storm. Because the water was so shallow at the site near Antarctica, the waves would have been even rougher. It turns out the waves are worse when the water is shallower! Combine that with all the icebergs around, and the captain did not think it was safe to wait out the storm there.
So we picked up and headed out to deeper water. We had a number of places we wanted to core, and it was decided to get some coring done while we waited out this storm. But to do that we had to go to one of our deep water sites. Far away (over 100 miles) from Antarctica and over 50 miles from most of the icebergs.
But the nice part, is we could still work while we were waiting on the storm to pass. We have very little time left out here, and we need to get as much done as possible.
So we cored for a few days, got a lot of very nice core, and the packed up and moved back to shallow water near Antarctica.
Of course, heading back inshore lands us in the land of icebergs again. And this time there are some big ones! Here are a few pictures!
And on this iceberg, if you look closely you will see a black spot. My camera is not good enough to pick them out, but those are penguins! Hundreds of them!
And here is one of me on the port side (this is what sailors call the left side of the boat) in front of an iceberg. It was very windy that day!
Now, Lambchop has gotten a bit of time off, so it’s time to get back to work.
After a sample is taking for Moisture and Density measurements, Lambchop has to weigh the sample. This is because to are going to figure out how much water is in the sample. We are going to do this by weighing the sample, and then putting the sample in an oven at 105 Celsius (221 Fahrenheit) for 24 hours! That is one whole day in the oven. We use 105 C because water boils at 100 C and we want all of the water to boil out. We leave it in the oven for so long to make sure it all boils out.
But before we can boil out all the water, we have to weigh the sample with the water. Now, on land weighing something is easy. You go stand on a scale and you are weighing yourself.
But, on a ship it is harder. This is because the ship is moving all the time. It is going up and down, left and right, forwards and backwards. Sometimes all at once!
Now the ship moving is a problem for weighing things because of how gravity works. Gravity is pulling you towards the center of the earth. It is doing with a constant acceleration. But when you are moving, you are accelerating in addition to gravity and that changes your weight for a while.
This sounds kind of weird, how can moving up or down change your weight? But you have probably exprienced this on your own already. If you have ever been in a car, and gone over a hill suddenly, you have felt your stomach rise up a bit. It is a very weird feeling, and it is because you were for that brief period of time, accelerating so that you partially subtracted from gravity. In other words, for that short time, you weighed less! If you have ever ridden a rollercoaster It is even more noticeable!
At the bottom of that hill, you suddenly felt pushed into your seat. That is because you are feeling an acceleration that is adding to gravity, so for that brief moment, you weighed more!
On a ship, you are always moving. Sometimes they are small movements. And sometimes they are big movements! For example, on land I weigh about 100 kilograms (or about 220 pounds, boy I need to go on a diet!).
However, in the last day for very short periods of time, I have weighed as little as 25 kilograms (about 55 pounds, or a quarter my normal weight). That is a great diet there. The problem is, a few seconds later, I weighed over 160 kilograms (350 pounds!) Yikes! I really, really need to go on a diet!
It is because the boat is accelerating as it goes over waves. This changes my weight for short periods of time.
But for weighing the samples, it is a problem. We solve this problem by having not one scale like you have a home, but two scales!
The way these pair of scales work, is we put a known mass on one of the scales. And we put our sample on the other. Then they are both run at the exact same time, and weigh the samples for 1 minute to get an average weight.
Since we know how much the mass on one scale weighs, we can figure out how much the ship is moving, and subtract (or add!) that to the other scale!
The samples only weigh about 10 grams (a third of an ounce), but these scales can weigh them down to a small fraction of a gram with accuracy. Even if the ship is moving!
Here is a picture of Lambchop with Jhon, who is one of the other Physical Properties Specialists. Jhon is from Spain.
So Lambchop and Jhon weigh each sample taken, and then the put the samples in the oven for a full day.
But you will have to come back tomorrow to see what happens next!