Monthly Archives: October 2013

Tromso–this is not your father’s Ikea furniture

Tromso–looks a little chilly, doesn’t it?

Well actually, it’s not any kind of furniture made of “some oak and some pine and a handful of Norsemen” (although listening to Jonathan Coulton’s song, it sounds like it could be), but it is another ground station.  It’s time to write about the Tromso Satellite Station (however, if you want to start with a smile, listen to JoCo’s song).  This station is located near the city of Tromso, Norway located over 200 miles NORTH of the Arctic Circle.  Yes, there is a city north of the Arctic Circle–one in which people are voluntarily staying.  This might explain why people live in Canada, Minnesota, and North Dakota–living in those regions is not as bad as living within the Arctic Circle (doesn’t mean they aren’t crazy for living there, though).

So, Tromso Satellite Station is over 200 miles north of the Arctic Circle then.  And sitting near this ground station is the operations center into which all data from satellites using the Kongsberg Satellite Services (KSAT) ground stations flows, the Tromso Network Operations Center, or TNOC.  According to the KSAT site, the TNOC remotely controls all their ground stations.  With ground stations like Troll (talked about on my site here) in Antarctica, it makes sense they’d remotely control it.  Who’d really want to live there?

So there’s a lot of action happening in Tromso.  But why place a satellite terminal/ground station there?  Just like Troll, Tromso is close to a Pole, but it’s the North Pole.  This means that using this antenna all by itself, they would likely be able to communicate with polar orbiting satellites every 90 to 120 minutes, give or take.  Please refer to my orbit lessons pages, particularly lesson 5, if you are confused.

Combine the Tromso ground station near the North Pole with the Troll ground station near the South Pole on the same network, and you’re suddenly looking at communicating with satellites every 45 to 60 minutes.  You’ve halved time between communications, and doubled the number of “contacts” (the time of communication between the satellite and ground station) between a satellite and the ground system.  So that means they can have satellite contacts at least twice per low earth orbit, 26 times per day.  This is a good thing if KSAT have satellites constantly needing to download data files, and if KSAT want to be able to deliver “products” to customers quickly.

Tromso sounds huge–KSAT say the Tromso Satellite Station consists of over 30 “multi-mission” (read:  most any satellite can use them) antennas.  According to the wiki, it was originally designed and built to support (pass satellite data back and forth) the European Space Research Organization (ESRO), but the station also supports the National Aeronautics and Space Administration (NASA) and Canadian Space Agency (CSA) (What??!!! Canadians have a space agency?) low earth orbiting satellites, too.  The wiki notes that KSAT customers can get their data in less than 30 minutes after a satellite contact.

There isn’t too much else on this ground station, unfortunately.  You can read more about it on the KSAT site and wiki.  But now you know:  Tromso isn’t a towel rack sold in Ikea–it’s a ground station AND a city in Norway.

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Aside

Um, yeah.  A committee.  That’s just great.  Another committee, but this one is different, right?  It’s a committee to “SAVE THE WORLD” (can I hear me some KUMBAYA brothers and sisters?).  It’s a United Nations committee.  So now we’re all … Continue reading

Splitting continent: it looks like a picture, but it’s ASAR

Most of the lessons I’ve posted on my site have dealt with imagery taken from camera payloads on satellites.  So it should be no shocker that I’ve relayed this NewScientist post of a nice picture of the Albertine Rift, showing where the Earth’s tectonic plates are splitting East Africa apart.  Here’s the picture, straight from the NewScientist’s site:

Click to embiggen

However, it’s not a true picture.  The image is really an aggregation of radar data, taken over the course of a year by the European Space Agency’s (ESA) Envisat.  The colors were added in afterwards to highlight changes in water level and the earth’s surface.  Envisat had several payloads on it, but it sounds like the data came from this one:  ASAR (Advanced Synthetic Aperture Radar).  According to the wiki, this payload had “sub-millimeter precision” for detecting changes in surface heights.  According the NewScientist post, Envisat collected this data between 2007 and 2008.  I’m guessing the data from Envisat and ASAR is surfacing now, as this image, because a lot of analysis needed to happen and a lot of crunching of numbers also occurred.  Or it could be just a slow news day.

Envisat was a sun-synchronous  low earth orbiting satellite.  I say was, because the Europeans lost contact with it in 2012 and they consider it a lost cause.  So thanks for adding a little more space junk to our orbits, ESA!!

Another secret Chinese launch

A Chinese Long March 2C rocket boosted another satellite with unknown intentions into orbit earlier today.  You can read all about it from NASASpaceflight.com’s posting:  Chinese Long March 2C lofts Yaogan Weixing-18 satellite.  According to the article, this launch was not officially announced.

There’s not too much advertised about Yaogan Weixing-18, although NASASpaceflight.com’s article does a great run-down of the other Yaogan Weixing satellites and the launch site associated with them.  Dragon in Space also has some descriptions of these satellites and the main descriptor for all of them, aside from “military reconnaissance,” is they are “remote sensing.”  This particular program is using either synthetic aperture radar (SAR) or some kind of “electro-optical digital imagery” (camera–they just need to say camera) payload on the satellites.

These also, historically, seem to be low earth polar orbiting satellites.

This launch comes hot on the heels of other Chinese activities, like this one about Chinese grappling satellites, posted yesterday.  Never a dull moment in China’s space programs…

Chinese grappling satellites?

Sneaky Chinese

I do hate posts like Gizmodo’s, asserting something that when you drill down, may or may not be true.  You just can’t tell.  But I guess that’s what link bait is:  something to get people to click on, true or not.  And when you drill down to the Washington Free Beacon post, it’s certainly not clear to me at all that Gizmodo’s, or the Beacon’s, assertion that one Chinese maneuvering satellite has successfully “hijacked” another of their satellites, is true at all.  And the only source attribution I see in the Beacon’s article is to “Pentagon officials.”  And most of what the Free Beacon mentioned in their post was old news.

That’s not to say the Chinese haven’t been busy.  We noted in this post the launching of these three satellites in July.  And Zarya, run by Mr. Robert Christy, has been tracking the three satellites and their activities, with good descriptions (graphs and all) here.  Not only that, Zarya goes into extreme detail on what it is the satellites seem to be doing.  You can read about the “waking up” of satellite “Payload A” here.  

It seems the Payload A raised its orbit by about a kilometer on 15 October.  You can read more about orbital maneuvers here, but what it means is the Chinese just increased the height of the satellite’s orbit by a little over half a mile (.62 miles).  Interestingly, Zarya notes the satellite wasn’t in view of any Chinese ground station, so that means all these were automated/preprogrammed maneuvers.  And then they note an object, which Space Track labeled “Payload A Debris,” had detached from Payload A, and shadowed Payload A from a fixed distance (in same Zarya post).

According to this Zarya post, Payload A raised it’s orbit again on 22 Oct moving it further away from the “Payload A Debris.”  And really, that’s all there is.  Nothing about “seeing” any grappling of one satellite by another.  Just very interesting maneuvers with objects appearing from other objects.  Zarya does say this really is all conjecture until the Chinese actually admit something is going on.  So, what day is hell scheduled to freeze over again?  It would be the day after that.

One other thing to note–Space Track admits their tracking is only good up to +/- 500 meters (at best).  So, imagine one football field (a little over that), multiply it by five.  Imagine there’s a “bubble” with the satellite at the center of it.   That bubble represents the amount of uncertainty of where the satellite is within it.  And the bubble has a radius of 5oo meters from where the satellite’s supposed to be.  So, now imagine another satellite with a similar bubble with a similar radius extending from it.  Now, imagine one satellite’s bubble starting to graze the other satellite’s bubble–and that’s as close as Space Track can monitor these things.  So there’s some room for error.  But some people, like Mr. Christy at Zarya, can also make intelligent guesses.  But that’s all they are–guesses.  If Space Track says they can only track a satellite’s location to 500 meters, then anything lower than that is just guesswork (as far as we know–there may be other ways to track these satellites).

Nonetheless, it’s good to know someone else is keeping an eye on the Chinese activities.  I wonder what the Indians are thinking about all of this?