Universe Today

Ikonos is a commercial Earth observation satellite owned by GeoEye Inc. It is the first commercial satellite capable of collecting panchromatic (black and white) images with 82-centimeter resolution as well as multispectral imagery with 4-meter resolution.

GeoEye is an image provider company that serves companies that require satellite map images such as Microsoft, Yahoo! and Google. In fact, Google has exclusive online mapping access to GeoEye-1, another satellite owned by the same company.

The zoomable images that you see on Google Earth, for instance, come from satellites like these. Sharper, more high-resolution images are accessible only to the government for obvious reasons.

Panchromatic or PAN images make use of black-and-white (monochromatic is a more appropriate term) photographic films that are sensitive to visible light of all wavelengths.

Panchromatic images have the advantage of having much higher resolutions than their multispectral counterparts. For example, if you recall our initial description of Ikonos earlier, you'll notice that its panchromatic feature can resolve points in an image that is 82 cm apart. By comparison, the multispectral feature of the same satellite can only resolve points up to as low as 4-meters.

If that already sounds amazing enough, consider this: in one of the sample images taken by Ikonos featured on the GeoEye website (please see the links after this article), one of them was a one-meter resolution image of Whistler Olympic Park, in Canada. It was taken by Ikonos from a distance of 681 kilometers above it while moving at a speed of about 6.4 kilometers per second.

A single scene taken by Ikonos has a swath of 11 km by 11 km.

All in all, Ikonos has already collected over 300 million square kilometers worth of images that has spanned every continent on the planet. It is an important source of information not only for entertainment purposes. Rather it is also used for national security, military mapping, air and marine transportation, and by regional and local governments.

A snapshot of disaster-stricken places can help rescue teams and concerned organizations apply the most suitable strategies for delivering aid and rescue operations. For example, a high resolution image taken of Bhuj, a town in the state of Gujarat, India, after the January 26, 2001 earthquake there was able to show where extensive damage on individual buildings was located.

Ikonos images can also be used as references for disaster management and urban planning, making efforts for such initiatives more efficient.

Here's a nice collection of pictures of Earth from Space featuring Islands, courtesy of Universe Today. Or if you want, you can check out a satellite image of Fraser Cain's house itself. You'll have to make a wild guess which one it is though as Fraser didn't label his house on the image.

Here's a link from the GeoEye website that features a magnificent collection of satellite images. If you want more information about Ikonos and its sister satellites, here's a link to the GeoEye website itself.

Tired eyes? Listen to some episodes at Astronomy Cast. Here are two that might interest you:

Stellar Roche Limits, Seeing Black Holes, and Water on Mars
The Search for Extraterrestrial Intelligence

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Google Mars is an online application that closely resembles Google Maps.

Of course, we now know that Mars does not have any roads (although whether it ONCE HAD a bustling civilization still remains to be determined). So instead of showing the Map, Satellite, and Terrain views a la Google Maps, Google Mars instead has the Elevation, Visible and Infrared views. Please see the right side of the screen cap above.

Clicking on 'Elevation' will reveal a shaded relief map using data obtained from the Mars Orbiter Laser Altimeter. The image is color-coded to give us an idea of the altitudes of the terrain we're looking at. The legend for the color-code can be found in the lower-left side of the screen cap. I've encircled one location on the map depicting a region with a 21-km altitude.

You can pan up, down, left, or right using the arrow-marked buttons in the upper-left side of the screen. To zoom in and out, just slide the slider tool. This is also found in the left side, right below the panning tool. See the screen cap where I've zoomed in to the encircled region.

The Visible Map or view is a mosaic of images obtained from the Mars Orbiter Camera, a device on the NASA Mars Global Surveyor. The gray-scale color was chosen for clarity. Here's the Cydonia region in Visible view. Cydonia's the place where the so-called Face on Mars was discovered.

Finally, if you select the Infrared view, you'll be shown a mosaic of infrared images taken by the Thermal Emission Imaging System (THEMIS) on board the NASA Mars Odyssey. Brighter colors indicate warmer areas while darker colors indicated colder areas. See the Cydonia region in Infrared below, where I've encircled the Face on Mars.

In case you're wondering why the infrared images are sharper, that's because clouds and dust (which are covering the surface) are transparent when viewed using infrared light.

If you've got Google Earth installed, you can find the same images there. In fact, Google Earth allows you to fly over Mars inside a virtual 3D environment.

Intrigued by the Cydonia region mentioned earlier? we've got an article written just for you here in Universe Today. There are also pyramids on Mars! Learn more about them here in Universe Today.

More discussions regarding the images used can be found in the Mars Global Data Sets webpage. If it's information about Mars in general you're looking for, head on to the Mars Global Surveyor webpage.

Tired eyes? Listen to some episodes at Astronomy Cast. Here are two that might interest you:

Stellar Roche Limits, Seeing Black Holes, and Water on Mars
The Search for Extraterrestrial Intelligence

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One of the coolest services we've ever used is Google Earth. This is a 3-D rendered version of the planet that you can spin around, zoom in and out. You can even zoom right in to the point that you're looking at your own house from above.

To get a copy of Google Earth, just point your browser at http://earth.google.com/. You can access a version for PC or Mac and even portable phones like the iPhone. Google Earth is completely free.

When you install and run Google Earth, the software accesses Google's servers and connects you to terabytes of geographical information. Because it would be too much to download at any one time, the service only transfers information at what you're looking at right now, and the lowest resolution that you need. As you zoom into a region, you can get more and more information and higher resolution images until you're seeing the most detailed information for Google on Earth.

You can use Google Earth, either by navigating around the planet, and zooming in where you want to go, or you can type in a address and Google will just take you there. There are also additional plugins you can install that provide even more geographical information, like climate change maps.

If you don't want to download and install a program like Google Earth, you can always access a service called Google Maps through your web browser. It doesn't look as cool as Google Earth, but you can access it anywhere and it uses the same satellite imagery and address finding.

And if you don't want to use Google, there are similar services from Microsoft and Yahoo.

We have written many articles about Google Earth for Universe Today. Here's an article about how people thought they might have seen the Loch Ness Monster in Google Earth, and how a geologist found a meteor crater in Google Earth.

We have also recorded an entire episode of Astronomy Cast just about planet Earth. Listen to it here, Episode 51: Earth.

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Thanks to the Internet and satellite imagery, every square meter of the Earth is being mapped out by satellites. These satellite images are available online, all you have to do is put in your address and you can see your house from above. Or you can browse around and look at any spot on Earth, for free. Next time you're wondering, can I see satellite pictures of my house, the answer is yes. Let's take a look.

Probably the best service available right now is Google Maps. You can access this service by going to maps.google.com, and then put in your street address. If Google can't locate your street address, you can always put in your zip/postal code, town or even state and it should be able to find it. Make sure you select the satellite overlay, so you can see an actual satellite image, and not just road maps.

Another service from Google is Google Earth. This is different from Google Maps because you have to download and install a software application to your computer. But once you do have this installed, you can look around the whole planet. It's very cool.

Another cool service is terraserver. With this application you can locate satellite images of your house and then print them off. You can also download high resolution images.

A big competitor to Google is Microsoft, and they have their Bing Maps service. Just like Google, you see satellite images of the whole Earth, and find satellite pictures of your house.

Keep in mind that none of these satellite services are live. There's nothing out there yet that lets you see the ground from space in real time. They're always images captured months or even years ago, and then stitched together into a larger image that you can scan around.

We have written many articles about using satellite images of Earth. Here's an article about Google Oceans and Google Mars, and how Google got a view of the Obama inauguration.

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As only a British tabloid (and Fox News) could, reports came out this week of the Loch Ness Monster being spotted on Google Earth. "This amazing image on Google Earth could be the elusive proof that the Loch Ness Monster exists," The Sun reported. Well, for one thing, this doesn't look *anything* like Nessie. Doesn't he have a long black neck? And another thing about this: it looks surprisingly like a …. boat. Imagine that, a boat on a lake captured by Google Earth! Astounding!
Look closely and you'll see the squared off back end of the boat (the stern), the rounded stern bow in front, and the tentacle-looking things are just the boat's wake. This looks very much like another image of a boat on Loch Ness on Bing (below). Click on the picture to get to the image on Bing and zoom out for the full effect.
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