The First Flare Amongst Many a Trail

As I wrote a few posts ago, I have recently found a program that lets me take a sequence of photos and combine them to give me nice startrails. Since there have not really been any clear nights recently, I have been going back through my photos to try to find times when I took a bunch of pictures all in a row without moving the camera.

This is one of the results of that search.

Near the center of the frame is the first Iridium Flare I ever managed to take a photo of. Going across the bottom is an aircraft. If you look on the water at the very bottom, you can see red lines all nicely spaced out. Those are the reflections of the aircrafts beacon on the water as it flashed every second or so.

Up near the top left of the photo is Polaris. It is the only star in this photo which does not appear to be streaked.

In the middle of the photo you can actually see the big dipper as well. The tip of the handle is about as far above the aircraft lights as the lights are above the horizon, and it is pretty much directly under the left end of the flare. The cup of the dipper is pointing towards the flare and Polaris. The stars in the big dipper are some of the brighter stars in this photo.

Once the clouds go away I am going to try to get some really good long star trails. I think that it will be possible to find a night where I could catch multiple iridium flares as well as the ISS in the same sequence since all they need to do is pass through the same part of the sky. I can set my camera up to take a photo every few seconds, and let it do that for hours.

A Line in the Sky

The ISS over Mount Tolmie on a clear night is a spectacular sight.

Here it is in all its glory.

Behind a Tree and into the Shadows

Another photo of the ISS. This time the station can be seen in the crook of the tree a little to the left of center of the image. As it goes behind the tree it fades. This is because at that particular point in its orbit it was entering the earths shadow. Sunset aboard the ISS happens once an orbit, or every 90 minutes or so....

Picture of a Picture

The International Space Station in all its glory. Since I have been posting pictures of it lately I figured that I could not hurt to post a picture of what it actually looks like. Since I have never actually been to space to take a picture of it, this will have to do. This is a mural/picture of it on a wall at the Kennedy Space Center Visitor Complex. Below the mural are the flags of all the contributing nations. Quite the cooperative effort considering the past century of international relations...

To get an idea of the scale of the station, each of the bronze colored solar arrays is 39 feet wide and 115 feet long. They are huge. Interestingly, since there is still just a little bit of atmosphere at the altitude of the space station there is a tiny amount of atmospheric drag. This is what slows satellites down and the reason why they need to be boosted every so often to maintain their proper orbit. The solar arrays on the ISS are huge and produce a huge amount of drag. 

They can be rotated around to change their orientation, and this is used by NASA to manage these effects. Often the station uses the night glider mode of operation whereby they orient the arrays in the direction of flight whenever they are in the earths shadow. This reduces the drag by a lot. They can also do that for entire orbits, but that reduces the amount of power they produce. Another use for them is to intentionally slow the station. This was used primarily for shuttle missions to reduce the altitude of the station to make it easier for the shuttle to reach. 

Finally they can also be used as solar sails. They are all double sided. One is shiny and the other is not. The not shiny side can be turned toward the sun and just absorbs all the photons. If the shiny side is turned toward the sun, all the photons bounce off and transfer some of their momentum to the station, helping it maintain it speed and therefore altitude. 

All of these effects are tiny, but they have a huge impact over months and years. Given that the cost of lifting a single kilogram of fuel to orbit runs at about $20,000, any reduction however small in the amount of fuel needed has a huge impact on the financial impact of the station.

Cloud on a Skewer

After scrambling to catch the ISS on Friday, I set out to do it properly on Saturday. This pass was not quite as bright, and it was a bit cloudy, but I think the clouds just added to it.

I think it looks like the cloud has been skewered by the streak of the ISS. In fact, the space station is a few hundred kilometers above the clouds.

It just strikes me as amazing the fact that there are people in there traveling around the earth at 7 kilometers a second.

If you too want to see the ISS there is an easy way to do it. First you need to open Heavens Above. The link is on the right side of the page. Once there you need to set your location and time zone as well as your elevation. That is all done in the configuration section at the top.

After that there are a whole bunch of different categories to choose from. They all show places and times where you can see bright satellites passing overhead or iridium flares or whatnot. There are also lots of pages of information about the planets.

Click on 10 day predictions for ISS. The table it brings you to lists all of the visible passes for the next ten days. Occasionally there will be a period with none. This happens when the station only passes over during the day or when it is in the earths shadow. These periods never last more than a week or so. When you find one you want to go see, click on the date.

That gives you all the information about the pass. I find the star chart to be particularly useful. I like to find a few easy points along it to identify, such as planets or bright stars so that I can figure out where it will go. Plan on being ready a few minutes early especially if you are going to be taking photos. Set the camera up at a point you know the station will pass through, then look for little moving dots in the sky along its path.

ISS is usually pretty bright so it is relatively easy to find, especially if you know where it is going to be. Make sure you are watching carefully as it only takes a few minutes to go across the entire sky. If you want a real challenge try to catch an iridium flare. Although they are brighter, they only last about 30 seconds or so and before and after the flare you cannot usually see the satellite. To take a picture of one you need to have the camera set up pointing at just the right place. Then to time it so you get the whole flare is pretty tricky too.

Three Russians, Two Americans, and a Dutch Guy

Last night at about 42 minutes after 9 o'clock I was trying to decide whether to go to bed and to sleep or whether to go out and take a look at Saturn and take some photos. I checked Heavens Above, and low and behold there was an epic and awesome ISS pass coming up shortly. Very shortly. It was due to start at 48 minutes after 9 and reach its peak at 51 minutes after, then disappear within another minute or two.

I grabbed camera, tripod and telescope and rushed out to the car. I drove the couple of kilometers to the top of Mt Tolmie, screeched to a halt and jumped out, camera and tripod in hand. I was right on time at 48 minutes after, but I still had to set up my tripod, and then find the space station and set up a shot. I had looked at where  it was going to be the highest in the sky, but I had forgotten to see where it would first appear.

I finally spotted it as it passed through the highest point. It was incredibly bright. It was almost as bright as it ever gets in fact. It was much brighter than Venus is these days. I managed to get this photo of it as it headed down towards the horizon. It is the very bright one in the middle.

This is not the most brilliant photo I have ever taken, but I really like it. On reason is because in that little bright streak there are 6 people. They go all the way around the earth every hour and a half. It is such an incredible achievement that this football field sized, million pound space station is floating around us with people in it.

Another reason I like this photo is the unexpected presence of two other satellites gracing it with their light. One is easy to see. It passes from right to left above the ISS. The other is much more difficult to see, and I only noticed it when I was looking at the photo afterwards, but there is another one passing through at a similar angle to the right of the ISS down closer to the trees. If you draw a line from where the ISS crosses behind the trees to the uppermost little fluff of tree on the right hand side that is where you will find it.

So here is to the astronauts and cosmonauts and all the thousands of engineers behind them who make human space flight possible.