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See the International Space Station in the night sky

When I was young I loved watching satellites go over at night. Seeing one was quite a hit and miss affair as there was no way to know when one would be coming. Usually they were only spotted on the trek back and forth from the outside toilet. All that has changed as there is now far more to see, good sites on the internet to provide details of when and where they will be visible at your location and there is also absolutely stunning apps for phones and tablets to help.

When I discovered how easy itcould be to see the ISS (International Space Station) I knew I had to give it a try.

The ISS is larger than I initially thought. According to Wikipedia it weighs a hefty 450 000kg and measures 72m wide, 108m long and 20m high. It orbits the earth every 92 minutes travelling over 27 000 km/h at a height of around 400 km.

So what do you actually see? Well, unfortunately you won’t see an astronaut waving at the window. What you will see is the sun reflecting off it causing a flare. At its best it looks like a very bright star in fact it can be over twice as bright as Sirius the brightest star. It moves quite fast and usually disappears within a couple of minutes.

Online information

If you want to give it a try, a site that I have found useful is Heavens Above. It not only tracks the ISS, but it also tracks other satellites that produce visible flares, planets and comets.

Start by selecting your location from a map, from a database of locations or enter your coordinates manually. Next look in the Satellites section and click on the ISS link to get the next 10 day forecasts. From there you can look up the next 10 days and so on. The table will show when the next passes and where in the sky it will come up and go down. The brightness is measured in mag and the smaller number the brighter, so -2 is much brighter than 2. While you’re at the site you may want to check out the Iridium flares for the next 24 hours. The Iridium communication satellites often cause bright flares, sometimes much brighter than the ISS, that’s what I’m going to be looking for next.


You don’t need a mobile device with an app, but it can help by showing you in real time where the ISS is. There are some great apps for both phones and tablets. The apps at the bottom of the post are just those that I have tried. All of them use the built-in 3D compass in your device to detect where it is pointing. Simply hold your device up towards the sky and you’ll see what’s up there on the screen. As you move your device around it will constantly update what you are pointing at with what is there. If you have not seen one of these apps in action your may be forgiven for doubting how well this could work, but I assure you it’s good and these apps are really really cool. I use the Night Sky for iOS to track the ISS.

Looking at the sky

Armed with the time of the next visible pass I wait until about 15 minutes before it is due to be visible. Then I open the Night Sky and follow it there. Here it is coming over Indonesia.

Map of the Earth from the Night Sky app showing the ISS

When it gets closer I switch to the sky view. In this shot I am aiming my iPad NE towards the horizon. The ISS is just below the horizon and heading up.

Screenshot from the Night Sky app showing the ISS

Five minutes after this we saw the ISS above the horizon. It got brighter the higher it went before finally disappearing into the Earth’s shadow.

Want to see a picture?

I intended to include a photo of the ISS pass. I spent a lot of time learning how to set my camera for the best shot. I did some test shots of stars beforehand. The small screen on my camera does not show the stars as they are not bright enough so I had to guess where the camera was pointing. The test photos came out alright. I set it up on the tripod and on the night I headed out into the darkness without using any light to protect my night vision. I did a series of shots, but, and I’m embarrassed to say this… I left the lens cap on. I’ll have another go and post the results up in another post.

More about apps

Below is a list of apps I have used and found useful for astronomy, but they don’t all show satellites. Remember, all of these use the built-in 3D compass in your device to detect where it is pointing.

Google Sky Map (Android)

This is the first star and sky map that I used and I installed it on my cheap LG Optimus One P500 phone. The app is produced by Google and it’s free. It shows stars and planets but not satellites. If you have an Android it’s a great way to see how these apps work for free.

Satellite AR (Android)

This app displays the location of satellites. It’s free which makes it worth a look. It does not seem to display the location of the ISS until it within 10 minutes of coming into view.

Star Chart (Android, iPhone & iPad)

The iOS and android app publishers have different names but the name and descriptions of the apps look the same so I don’t know if they are the same or not. I use the iOS version on my iPad. It shows stars and planets, but not satellites. It’s not free either, it cost me A$2.99, but it is currently on special at A$0.99.  So why have I included it? Because on my iPad 3 it is smooth and the display is simply gorgeous. Have a look at this image.

Sample Star chart screenshot. Click to see it full size.

Screenshot from the Star Chart app

Sample Star chart screenshot. Click to see it full size.

The Night Sky (Android, iPhone & iPad)

I got this for my iPad on sale for just A$0.99. There is an upgrade option to get more information about objects, but you will not need it to track the ISS.  There are two viewing options. The first is the usual point at the sky and view and the other is a map of the world showing the satellites position in real time so you can see where on earth the ISS is currently over. This is the best app I have found for the iPad to locate the ISS. It is also available for Android and I have tried the free lite version on my Android phone, but I could not get the satellites to display of it, so perhaps it is just the paid version that has that feature. One feature this app has that I have not found on other ones is that it plays some really neat spacey music while it is running. Standing outside in the dark with the stars with the music playing it feels like I’m about to be visited by an extraterrestrial.

Is it worth it?

If you’ve got access to an area where you get a good view of the sky without too much light pollution it’s definitely worth it. All our family enjoyed it. It’s something for the bucket list for any nerd.

Computers: The 1990’s – You paid how much?

Black and White laser printer. A bargain in 1994 at $1000

Recently I found a couple of old catalogues in our filing cabinet that I had kept for some unknown reason. I was looking at the prices of computers and was reminded what an expensive hobby it used to be. The catalogue was from July 1996. There were 14 desktop computers ranging from A$2999 to A$4099 with an average price of a whopping A$3412. The $4099 one was described as “Unprecedented power & storage for small business and accounting needs”. Its specs were:

  • 100MHz Processor
  • 1.2Gb HD
  • 12Mb RAM
  • 4X CD ROM
  • 15” Monitor
  • MYOB software

It’s hard to believe that was enough power for a business, but I remember using something similar at the time where I worked and it seemed fine for what we did.

There is also seven laptops listed ranging from A$2999 to A$4699 with an average price of A$3541. For $4699 you could have:

  • 75MHz Pentium processor
  • 8Mb RAM
  • 9.5” Active Matrix TFT display
  • Removable 810Mb HD
  • Lithium-Ion battery,
  • BitBLT Video Accelerator
  • Windows 95

I don’t think that these prices were particularly high for that time, not around here anyway. At that time the Australian dollar was valued much lower than the US dollar which accounts for some of the price difference we now have. According to the RBA Inflation calculator that calculates increases of “baskets of goods and services”, that average price of $3541 back in 2006 would now (or at least in 2011) be an incredible $5,274

Examples of my excessive spending

Here are some of the things that I purchased around that time:

  • Microsoft Office, purchased in July 94. This was version 4.3 and came out for windows 3.1? Fortunately it also worked with Windows 95. I got a discount because it was an upgrade from Works. Price: A$525
  • Diamond CD reader and software kit. Purchased in March 95, this kit had a 4x CD reader (not writer) and a few games and other software including Compton’s Encyclopaedia. Price: A$799
  • 8Mb RAM, yes that’s correct 8Mb, not 8Gb. August 94. Price: A$620
  • B&W desktop Laser Printer. July 94. Price A$1000. It was ok, but not as good as my current laser printer which were selling recently for $49.

Other than making me feel sick at the thought of having wasted so much money, I can at least take comfort that computing is more affordable now.

Redundant faster?

Back in those days second hand items were expensive too. I don’t know if it is my imagination, but there seemed to be a bigger performance difference between new computers then and those 12 months older, and not just for intensive software like games, but even for basic things such as word processing. Because people paid so much for new equipment many expected to sell them for a high price a year or two later, often asking as much as an equivalent new one with the same specs.

I bought a second hand tower in 1994 that had 386SX CPU, 4Mb RAM, 80Mb hard drive, 14” Monitor for $1500. That price was typical around here. Now I would have to pay our local recycling centre to accept it. It did come with a large solid case which had lots of room for expansion, but I never made use of it as extra bits cost so much. It had flip out feet on the bottom that I had to remove just to make it fit under my desk.

386SX PC. $1500 in 1994

386SX PC. $1500 in 1994

It’s not just that hardware is cheaper. A lot of software is cheaper or free too. I remember being quite excited when I purchased Cinemania on CD. Now IMDb  contains everything and more that I want to know about movies and is available online. The quality of software that I paid $70 or $80 was no better than those that are available online for free now.

We now pay for the internet

I do now have an ongoing internet access cost that I did not have. I have been paying more each year for that, but that’s because I now have a family of four that all love to use it. I still feel I’m much better off now, but it’s worth considering this cost.

It’s good though, isn’t it?

When I think of the cost of my iPad, I remember I paid less for it than the floppy drive for my Commodore 64, which was over $1000 if you take inflation into account. When someone displays a look of horror when I hear someone mention they have actually paid a few dollars for an App, I remember what it used to be like. I guess it’s still easy enough to spend lots of money on computers, but it no longer needs to be that way. I can’t help thinking how much better it is now.