April 27, 2012

Nozzles

This is set of thrusters on the side of the service module of an Apollo spacecraft. I think the nozzles look really cool with the metal all changed color because of the heat of their test firings.

April 25, 2012

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.

April 24, 2012

A Truly Large Building

This one is a bit different. This is the Vehicle Assembly Building (VAB) at the Kennedy Space Center (KSC). The VAB was built in the mid 60s as a place to assemble the Saturn V rockets used for the Apollo program. The building is 526 feet tall, and was for nearly a decade the highest building in Florida. In fact, standing at the top of the VAB you are nearly 200 feet above the highest hill in Florida which lies at just 345 feet above sea level.

The building is so large that even with the massive number of fans and ventilators in the building, a particularly humid day can cause rain clouds to form inside the building. Since this photo does not really have much in the way of  a sense of scale, each of the stripes on that flag are the width of the lane on a road. If you laid the flag out on a football field, with one end on the end line, the flag would reach all the way to the 30 yard line at the other end of the field. If you laid this entire side of the building down, you could cover up six and a half full sized NFL fields including the end zones.

As I said, this was used first for the vertical assembly of Saturn rockets just as its name may suggest. Later, and in fact up until just last year it was used for the assembly of the space shuttle. The orbiters were processed in the smaller facility you can see to the left, aptly named the orbiter processing facility. They were then mated with their external fuel tank and solid rocket boosters in the VAB before being driven out to the pad on one of the crawlers.


April 20, 2012

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....

April 19, 2012

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.

April 18, 2012

A Flare of the Iridium Type

Another iridium flare. This one happens to have been caused by the satellite Iridium 60. It was launched March 30th 1998 from Vandenberg AFB in California aboard a Delta II rocket along with four of its iridium buddies.

Like all the Iridium satellites this one is a communications satellite for satellite phones. It is in a polar orbit going from pole to pole and back in about 100 minutes. It is in orbit almost 800 km above the earth.

I don't have much else to say about this picture. I took it on saturday night from Mt Tolmie. It was a 30 second exposure.


April 16, 2012

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.

April 15, 2012

Goddess in a Tree

It was sure a beautiful night on Friday. After I rushed up and took the photo in the last post, I set up my telescope to take a look at Saturn. I also took some photos of Venus.

Venus is in the tree in on the right. A car going by left some cool light streaks on the left and the city lights make some interesting colors in the sky, I quite like this photo if I do say so myself. The trees look so weird and alien...

April 14, 2012

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.

April 13, 2012

A Bright Pre-Easter Surprise

An elusive iridium flare. Nearly as elusive as posts to my blog have become!

This one was a kinda wimpy one as flares go, only reaching a brightness of -2 or so, about the same as the brightest planet in the sky right now, Venus.

It was good natured enough to take place right near the big dipper as you can see. It also avoided the nearly full and very bright moon which was lighting up the clouds.

I took this at the astronomy open house from the roof of the Bob Wright Building at UVic. Since the satellite takes about 45 seconds to go from invisible to peak brightness and back to invisible, and it is moving across the sky very quickly it is very hard to take a picture of a flare and time it right so you get the whole thing in the exposure.

If you look closely you can see that I bumped the camera a little as I was taking my hand from the shutter. It gave the left bit a little bit of a wobble.

I have some new photos to share, and after my exam tonight I may go out and capture some more if it stays clear. I hope to be back on track with posting now.

April 4, 2012

Welcome Back...Again

As you may have noticed, I have been very bad at posting lately. I have no good excuse except that this is the final week of the final term of second year university, and I am taking the maximum number of courses my university allows you to take. Tomorrow is the last day of class however, and after that is easter, and after that is all done, I am going to really try to make sure I get something up every day. The thing is that I like to take my time and write a good post. But as I just said in the previous sentence, that takes time, and time is not something I have had a lot of recently. So here is to onwards and upwards, and more frequent posts!

This is a photo from the 6th of March. A few posts ago, I posted a picture from about 20 minutes earlier. In this shot, the sun's light had almost completely gone, and the lights of the city were taking up their duty of lighting up the sky. Through the light clouds you can see a few stars, but the main features are Venus and Jupiter. Of course by now, Jupiter is much lower in the sky than Venus, and drops below the horizon just a short time after the sun sets.

Tonight at the UVic observatory open-house, we will have lots to look at, provided those pesky clouds clear off...The moon is almost full which is a bit annoying as it eats up all the faint objects in the sky because it is so bright. Then there is Jupiter for a little bit, Venus, Mars, Orion's Nebula, an coming up a bit later is Saturn. Pretty soon it will be high enough to get a good look at it, and it will keep getting higher all summer, replacing Jupiter as the best big planet to look at.

This year will be a good one for the observation of Saturn. The last few have not been great because when the planet is in our night sky, the rings were directly edge on  to our view. Now though they are not, and they are getting more and more tilted every day. They will be the most tilted to us around 2017.

I will do my best to keep posting regularly, but no guarantees for the next couple weeks.