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Posts Tagged ‘Satellites’

Knee Deep in Satellite Debris

March 1st, 2009 No comments

Click to view the live satellite debris tracker

A quick update on the Google Earth browser plugin based tracker displaying the debris from the collision between the Iridium 33 and Cosmos 2251 satellites on February 10th.

I mentioned the possibility that the number of fragments tracked in the Norad orbtial elements might increase. Well they have. Threefold over the past week, from 134 up to 406.

Remarkably the application still smoothly animates all objects in real time, even on my single core PC, but inevitiably it sucks up more processing power. You may find it now lags on an old machine or slower browser. If the number increases further I may have to either cap the number displayed or ditch the smooth animation.

Anyway, click on the image above to see it in action.

Related: Here’s a neat simulation from Analytical Graphics which includes a statistical break-up model of the satellites immediately after impact.

Satellite Collision Debris Tracking in the Google Earth Plug-in

February 23rd, 2009 5 comments

Live Satellite Debris TrackerFollowing on from my visualization of the satellite collision over Siberia on February 10th involving Iridium 33 and Cosmos 2251, here’s an Google Earth browser plugin based tracker for the debris from the crash.

Full screen version here: http://barnabu.co.uk/geapi/debris

The application loads up to date Norad orbital elements on start up, and propogates the orbits of all 134 fragments smoothly in real time.

Remarkably the Google Earth API is powerful enough to move placemarks thousands of times a second to give the impression of completely smooth motion for hundreds of objects. On top of that modern browsers are fast enough to run all the Math heavy orbital computation in Javascript. So this is really-real-time tracking, not with delayed updates. Something that can’t be done in regular Google Earth.

I’m guessing the number of objects could increase over time as more wreckage is discovered. If that’s the case, just have to see how well it scales.

Space Crash, Update

February 12th, 2009 1 comment

Space Crash! Google Earth PluginBecause you can never have too many ways to see the same thing. This is a browser based version of my satellite visualization from ealier today. Showing the February 10th coming together of US and Russian communication satellites, Iridium 33 and Cosmos 2251 over Siberia

Same idea as before, plots the locations of the two objects in the minutes leading up to the collision, but this one runs inside the Google Earth Plugin.

Read more…

When two satellites collide, in Google Earth

February 12th, 2009 No comments

Satellites Colliding in Google Earth

Satellites Colliding in Google Earth

This is a quick Google Earth timeline animation of the recent satellite collision between the Russian Cosmos 2251 and the US iridium 33.

Update 2009-02-14: Two ways to view this now.
– A Google Earth browser plug-in version
– Or the original KML file for regular Google Earth below

Cosmos 2251 and Iridium 33 Collide

Use the time slider at the top of the screen to play the file back. The animation tracks the objects during the 6 minutes leading up to impact. Also included are the orbital paths (ground tracks) of the two objects between 16:00 and 17:00 GMT on February 10th.

Location data is based on the orbital elements for the two satellites, from Celestrak.

Interactive Spiders and Charts

December 24th, 2007 5 comments

GPS Animation and Charts, Google EarthA couple of updates to my recent Google Earth GPS-satellite visibility animation:

Firstly, you can now change the viewing location to anywhere on Earth.  To do this, right click on the Location folder (with the blue dot) in the side panel and select Refresh.  The animation will then centre on the current view.

Secondly, the visualization displays a Screen Overlayed bar chart by hooking up to the new, and very slick  Google charts API.   The chart shows the duration, in hours, specific numbers of satellites are visible. The idea being to demonstrate how the distribution profile changes with location.

As a secondary (secondary) option you can view a 24 frame animated bar chart.  Where I cumulatively add the current hour’s stats, shown in red, to all the previous hours’ , shown in green.  A bit OTT, but interesting to see how rapidly the API dynamically generates the images on demand, and GE caches them.
Edit (2007-12-26): removed this option temporarily – see comments.

Download the file here:

GPS Animation ~200kB

There’s a useful tutorial on how to create and embed charts in KML balloons on the official Google Maps Blog.   Only difference I found in adapting it for KML Screen Overlays (or Icons, Ground Overlays and PhotoOverlays for that matter) is I needed to use &  instead of & in the URLs.