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Google Earth Pro print options advanced formating

jeu 10-03-2016

When Google Earth Pro was first made available for free we had a look at the advanced printing options in Google Earth Pro that are not found in the standard version.

We recently had an enquiry from a GEB reader about how to change the background colour of the Title element. This YouTube video from Google gives some idea about what is possible and points out that the HTML Area element can contain just about anything that can be done with HTML, including an external website. However, it doesn’t mention that the Title and Legend elements can also be styled with HTML and CSS.

If you want a fancy title, one easy solution is to simply turn off the title element and use the HTML Area element instead, as that is easier to work with. However, if you want more than one section of text on your map you may find it easier to use both.

To change the background colour or transparency of the Title element, have a look at the contents of the HTML Area element element to get an idea of how it works there. The HTML Area element has a DIV with an id of ‘white_box’. It turns out that both the Title and the Legend boxes also have an identical DIV.

So for example, if you want to get rid of the background in the Title element simply edit the element and paste the following text anywhere. We recommend putting it at the end of the description for neatness.

<style>#white_box{background:none}h1{color:white}p{color:white}</style>

The above also changes the heading and description to white to make them more visible. Note that the heading can be styled with the H1 tag and the description using the P tag.

The Legend element works exactly the same way – simply paste the above or your own styles into any of the legend entries.

Unfortunately, it seem that CSS gradients are not supported.

If you spend a long time working on the print settings be sure to save them, as they will otherwise be lost when you exit Google Earth Pro.

The above Title was formatted by adding the following text to the description:

<style>#white_box {background-color: #a2d7d8;border:5px #fcd059 solid;border-radius:20px}h1{color:#de5842;text-align:center}p{color:black;text-align:center;font-style:italic;font-weight:bold}</style>

The post Google Earth Pro print options advanced formating appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Google’s Skybox Imaging renamed Terra Bella

mer 09-03-2016

Google has just announced that Skybox Imaging has been renamed Terra Bella. The new name is intended to indicate a change of focus from just a satellite imaging company to pioneering the search for patterns of change in the physical world.

Google acquired Skybox Imaging back in June 2015. We have not seen Skybox imagery in Google Earth, mainly because it is lower resolution that than offered by Google’s usual imagery suppliers. Despite the lower resolution, Skybox has produced some interesting products over the years. We saw a gif animation of the Burning Man festival and in the same post you can see the first HD resolution video of Earth from space. We also had a look at Skybox’s image of the November 2014 Poppy display at the Tower of London. We love the Google Chrome extension “Earth View” and we noticed that it includes a few images from Skybox Imaging. In October 2014 Skybox announced the Skybox for Good programme, which works with non-profits to provide fresh satellite imagery where they need it.

Terra Bella plans to launch a lot more satellites in the coming years and we hope to see great things from them in the future.


The Burning Man gif animation.


SkySat-1 Video of Mount Ontake, Japan on October 16, 2014. Mt. Ontake erupted on September 27, 2014.

Be sure to visit the new Terra Bella website for more examples of their products. The new Terra Bella blog can be found here.

As of this writing, the old domain, skybox.com seems to be inaccessible, making any links to the old Skybox Imaging blog no-longer valid.

Thank you to GEB reader Eric for letting us know that the Terra Bella name is derived from the street where they have their offices (Terra Bella Ave, Mountain View, California, USA).

The post Google’s Skybox Imaging renamed Terra Bella appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Fifth Anniversary of the Japanese Earthquake and Tsunami

mar 08-03-2016

This week marks the fifth anniversary of the Great East Japan Earthquake and Tsunami. Google has been using Street View and aerial imagery to record both the devastation caused and the subsequent rebuilding process. They have recently released a new batch of Street View imagery for some of the worst affected areas, allowing you to see the changes over the last five years. Read more about it on the LatLong blog. You can also explore the imagery at the “Great East Japan Earthquake Digital Archive Project”.

Google has also been gathering aerial imagery of Japan, including the affected areas. They have recently released some imagery dated February 2016. It is not yet in ‘historical imagery’ but can be found in the default layer. It is unusual for aerial imagery in that it shows quite a lot of snow cover. The LatLong blog shows an animation of one location showing the situation before the Tsunami, the devastation caused and the recovery and rebuilding process to date. Below we show similar images for another location. You could do the same for almost any location along the North East coast of Japan.


August 2010, before the Tsunami.


March 2011, showing the devastation after the Tsunami.


February 2016, showing rebuilding taking place. However, they are avoiding building houses within the danger zone.

We have marked out the areas covered by the new 2016 aerial imagery, which you can view in Google Earth with this KML file.

Google did some similar imagery comparisons one year after the disaster, which we covered here.

The post Fifth Anniversary of the Japanese Earthquake and Tsunami appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Total Solar Eclipse March 8-9, 2016

lun 07-03-2016

This week there will be a total solar eclipse starting in the Indian Ocean, crossing Indonesia then out into the Pacific, ending up North East of Hawaii. A partial eclipse will be visible longitudinally from India to Alaska and latitudinally from China to Australia. An interesting side effect of the fact that it crosses the dateline is that the eclipse starts on March 9th and ends on March 8th.

One of our favourite resources for eclipses is the HeyWhatsThat eclipse page. It depends on the Google Earth plugin, which was set to be shut down last December, but has been kept running by Google so far, and you can still view the HeyWhatThat website with Firefox. You will have to allow the plugin to run.

Another excellent resource is Xavier Jubier’s site, which has this page that has a lot of detailed information about the eclipse and local viewing conditions and this map, which shows the path of the eclipse and a number of viewing locations, including a number of cruise ships and aircraft that appear to be planning to view the eclipse.

If you don’t live in the path of the eclipse then it is possible to view it online. It will be live-streamed by Slooh, a community telescope service. However, to view it you need to sign up as a member. They are currently offering one free month’s membership, but they do seem to require a credit card.

See here for previous solar and lunar eclipses.

The post Total Solar Eclipse March 8-9, 2016 appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Lexington Financial Center vanishes

ven 04-03-2016

Thank you to GEB reader Jackson for letting us know that the Lexington Financial Center, a tall building in Lexington, Kentucky, is completely absent in the recently released 3D imagery for the area.


What the new 3D imagery looks like.


What the old 3D imagery looks like.

To see the old 3D user-created models simply switch to ‘historical imagery’ while keeping the 3D buildings layer turned on.

A couple of blocks away, just visible at the left hand side of the screen shot above and shown in close-up below, there are some smaller buildings that have been flattened.


Roof top air-conditioning units appear to be at ground level.


The missing buildings are smaller than the Lexington Financial Center, but not insignificant.

So what caused this? Without knowing Google’s exact process we can only guess. The Lexington Financial Center, as well and one of the smaller buildings, are covered in glass. We know Google Earth’s 3D imagery creating process has trouble with water and highly uniform areas. So it could be caused by something related to the very uniform surface of the Lexington Financial Center or something to do with reflections in the glass being different from different angles, which would throw off the stereoscopic algorithms. Notice in the older models above, there are strong reflections in both the Lexington Financial Center and one of the smaller buildings. Notice also strong shadows and light reflected from the windows between the two smaller buildings. If imagery was captured at different times of day then the patterns will have moved.

We do not know how common this is and suspect that Google manually guides the algorithm in many cases and that in this case their quality checkers missed these buildings. Google typically takes quite a long time between capturing and releasing 3D imagery, so there must be quite a lot of manual involvement in the process. There is not enough aerial imagery in this location to accurately date the 3D imagery. We are fairly sure it was captured after the most recent aerial image from September 2014. Our guess is somewhere in the first half of 2015.

When we had almost finished writing this post, we discovered a new clue. If you zoom out until the buildings are almost too small to see, the Lexington Financial Center appears, as does another nearby tall building that we hadn’t previously realized was missing.

Additionally, you can get quite close and switch rapidly between ‘historical imagery’ and normal mode and you will see the various buildings mentioned appear for a moment and then rapidly vanish. We have noticed this effect previously with different imagery sets being visible at different zoom levels. We suspect that in this case Google does have a corrected 3D model but, by accident, uploaded the wrong model for the zoomed in version.

We considered grabbing the user created models and putting them into Google Earth alongside the new 3D imagery. However, the links in the Google Earth popups no-longer work, so we had to manually search the SketchUp 3D warehouse for the model of the Lexington Financial Center. We did find it here, but the export to KML does not work properly. It produces a badly formed KMZ file that does include the model but no associated KML file or textures. If you live in Lexington and do want to have the Lexington Financial Center back, you could download the Sketchup version of the model then use Sketchup to convert the model to KML format.

If any of our readers knows of any other large buildings that Google’s 3D failed to model, please let us know in the comments.

To find the locations of the missing buildings in Google Earth, download this KML file.

The post Lexington Financial Center vanishes appeared first on Google Earth Blog.

Catégories: Sites Anglophones

How it works: Classifying Placemarks by Region

jeu 03-03-2016

We recently created a JavaScript tool for classifying placemarks by region. This post is about how it works.

The basic idea is actually quite simple. To determine whether or not a point is inside or outside a polygon, simply draw a line from the point in question to a point you know is outside the polygon and then count how many times it crosses the polygon. If the number is odd, the point is inside the polygon, if the number is even the point is outside. In our case, we assumed that the polygon being tested does not go around the North Pole, so we draw a line from the point to the North Pole and then count how many edges of the polygons it intersects.

Below is an example of a place in Japan being tested:


The green line is drawn from the point being tested to the North Pole. The red lines are edges that we identified as being crossed by the green line. The white diamonds are the intersections. There are fifteen intersections, therefore the point is inside the polygon.

To see it in Google Earth download this KML file.

To actually identify which vertices the line crosses, it is necessary to find the intersection between the great circle on which the edge lies and the great circle on which the line we are testing lies and then check whether the intersection lies between the two ends of the edge and also whether or not it lies between the two ends of the line being tested. All this is complicated by the fact that any two great circles actually have two intersections on opposite sides of the globe (the antipode). The original algorithm we had for finding intersections that we used for the circle drawing tool sometimes found the intersection we wanted and sometimes the antipode. We found that when it found the antipode it was not as accurate as when it finds the intersection we are interested in, so we had to improve the algorithm to try and ensure it finds only the intersection we want.

To improve performance we first check whether or not a point is in the same region of the globe as the polygon being tested and don’t actually bother with the above algorithm if they are in different parts of the globe.

The reason we were working on the code in the first place is that when we were working on this post about recent progress in 3D imagery we noticed a significant discrepancy between the total areas for the timeline vs total areas in the ‘sorted by country’ section. To easily identify mistakes we wanted to match up polygons from the two sections. To do this we needed to know whether any two polygons overlap. The way we achieve that is to test every point in every polygon and see if it is internal to another polygon. If it is, the two polygons overlap.

The post How it works: Classifying Placemarks by Region appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Street View portals to Mars, the Moon and Atlantis

mer 02-03-2016

Recently, we had a look at recent additions to Street View. We also included a map of changes over the past month. There were two spots in the ‘changes’ map that we found particularly interesting.

The first is in the Atlantic Ocean and upon closer inspection is very close to an underwater mountain named ‘Atlantis Seamount’. We were able to see the blue Street View indicator in Google Earth but were unable to enter Street View at that location.

However, in Google Maps you can enter the Street View, but you get instantly teleported to Santes Creus Monastery in Catalonia, Spain.


Santes Creus Monastery, Catalonia, Spain. See in Street View

The second location is in Angola. This time we were able to see it in both Google Maps and Google Earth and it turns out to be a portal to the Moon!


Portal to the moon found in Angola.


If you enter Street View at coordinates -9.097507,15.484863 in Angola, you will see Lunar Street View imagery. See in Google Maps.

We had heard about both Lunar and Martian Street View imagery before. Thank you to GEB reader ‘poli’ for giving us a link to a Martian image in the comments of this post. We had previously not managed to find a way to view it from within Google Earth. After we knew what to look for, we tracked down the Martian portal in the province of Papua, Indonesia.


The portal to Mars can be found at coordinates -4.5895946,137.4492225.


Street View imagery on Mars captured by the rover Curiosity. See in Google Maps

Not far north of the Atlantis portal, in the Atlantic Ocean at coordinates 40.571082, -29.539372, there is another Street View portal that takes you to underwater Street View of the Galapagos Islands.

To view the Mars and Moon locations in Google Earth download this KML file

You cannot view Street View in the ‘Mars’ or ‘Moon’ modes of Google Earth or Google Maps because the ‘yellow man’ is not shown.

As we have mentioned in the past the blue Street View layers tend to show different locations at different zoom levels and the blue markings for the above locations can only be seen when zoomed out quite a long way and not at all in Google Earth for the ‘Mars portal’.

In order to see the blue Street View outlines when zoomed out, first zoom in until you see the yellow man, hold him above the map and then zoom out with the ‘-‘ key on the keyboard. You can also move around with the arrow keys.

If anyone knows of any Street View on Mars or the Moon other than the two photospheres featured above, or if you know of any other portals where entering Street View in one location takes you somewhere totally different, please let us know in the comments.

The post Street View portals to Mars, the Moon and Atlantis appeared first on Google Earth Blog.

Catégories: Sites Anglophones

The best of Google Earth for February 2016

mar 01-03-2016

There have been no major imagery updates since mid-January. The latest imagery to be found in ‘historical imagery’ is dated January 11, 2016. However, Google did add an image dated February 2nd, 2016, which includes the stadium where Super Bowl 50 took place. As far as we know, it was the only image added in that update, but it has not been migrated to historical imagery, so we don’t know for sure.

There were some Street View updates, most notably the Island of Réunion, which we covered in yesterday’s post.

3D imagery continues to be rolled out and we had a look at the progress made so far.

At the end of January, Google dropped the three Google Earth Pro only layers. This was because Google Maps Engine was being shut down, as it had been deprecated a year ago. We then discovered that the Google Earth Traffic layer also depended on Google Maps Engine and was also dropped. Judging by the various comments and emails we have received, the US Parcel Data layer and the Traffic layer will be sorely missed by a number of people.

We had a look at some Google Earth animations created by Steven Ho. We especially liked the Taiwan Lantern Festival animation, as Steven managed to get the lanterns to appear to glow, even though Google Earth does not have a very sophisticated lighting engine. Try them out in Google Earth by going to his blog and specifying the coordinates you would like.

We created a number of JavaScript tools in February for manipulating KML in various ways. We started with a tool for translating and rotating KML. Then we created a tool for labelling polygons. We then tried drawing circles based on three placemarks on the circumference. At first we had a little trouble with accuracy, but were able to fix all the bugs and it now works remarkably well. We also created a tool for classifying placemarks by region and to demonstrate it we used a global map of country outlines which we first needed to convert from the shapefile format.

Frank wrote a post about Space Engine a ‘Google Earth’ for the universe. If you haven’t tried it out yet, then consider doing so, as it is definitely worth a look. It can be downloaded here.
 
 
 
 

We had a look at ghostly images in Google Earth’s 3D imagery and what causes them.
 
 
 
 

In reference to the recent detection of gravity waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO), we had a look at LIGO and a variety of other large scientific instruments. We followed that up by having a look at various radio telescopes.
 
 

We had a look at NASA’s ‘damage maps’ of last year’s earthquake in Nepal.
 
 
 
 

We continued our GEB FAQ series by discussing how to add your own imagery to Street View.
 
 
 
 


We had a look at Landsat coverage and found an interesting gap at the antimeridian.
 
 
 

To celebrate Valentine’s Day we had a look at various heart-shaped islands in Google Earth
 
 
 

The post The best of Google Earth for February 2016 appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Street View comes to Réunion

lun 29-02-2016

Réunion, a French Island in the Indian Ocean not far from Mauritius, has recently received Street View. We found that although the coverage shown by the blue lines is quite extensive we were not able to access it in a number of areas. For example, Îlet à Cordes shows blue lines but if you try to enter Street View there in either Google Earth or Google Maps it does not succeed.


Changes to Street View between January 28th, 2016 and February 28th, 2016. Changes marked in red. Existing Street View in blue. Large version


See it in Google Maps . With nothing to judge scale by, this volcano looks deceptively small and close. It is actually about 3 km away and has a crater over a kilometre wide at its peak. The whole thing is sitting inside a much larger crater, the edge of which the photo was taken from.


See it in Google Maps. Réunion has some very steep mountains. We thought this spot looked especially beautiful, with the sun just peeping over the mountain.

Other new Street View includes expansions to coverage in Ecuador, Bolivia, Uruguay, Brazil, The Philippines, Ukraine and Russia. And the Google LatLong blog lets us know about some US stadiums that have received Street View. There is also some new Street View of Ellef Ringnes Island in the far north of Canada. It is dated April 2014, but appears to have only recently been added.


See it in Google Maps. If Réunion was too hot and tropical for you, then try exploring Ellef Ringnes Island in northern Canada.

The post Street View comes to Réunion appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Ghostly planes in Google Earth 3D imagery

ven 26-02-2016

We recently came across this story about what at first sight appears to be a plane at the bottom of a lake. Today we are looking at how this ‘ghosting’ effect comes about.


The two ‘ghostly planes’ noted in the article above.

We have previously discussed the ‘rainbow effect’, which has even inspired artists. That is caused by the way satellite cameras work, taking multiple photos in quick succession with different colour filters.

However, the planes in this case are in 3D imagery, which is not captured by satellites, but from aircraft. An aircraft flies over a region capturing multiple images in succession. It then comes past again at a later time and captures more images. In this post we noted that a water tower had been photographed from six different directions at two different times of day. Next Google uses an algorithm that uses the stereoscopic effect to reconstruct the 3D shape of objects. However, this fails for moving objects. At airports we often see aircraft that were captured well from one side but had left or moved before the other side was captured and they end up looking hollowed out.


Planes that moved before all the second set of images were captured.

Vehicles have a similar problem:


You can read the number on the roof of the bus, but the rest is a ghost.

The technique used for reconstructing the 3D has particular problems with water. The surface of the water is constantly changing, which confuses the algorithm. Uniform surfaces with no markings also give problems. Google often completely turns off the 3D generation for large rivers, lakes and the sea. However, they still have multiple photos for each location, which the blend together. As we showed you in this post, this can lead to some interesting effects.

Based on carefully studying of a location in Venice, Florida, USA, we believe that there are four images captured in fairly quick succession, followed by another four at a later time, resulting in anchored boats appearing to have eight copies altogether, but moving boats only appear to have four images, unless you can figure out where they were on the second pass. There are also some much less distinct images for each boat, but they are harder to count or work out when they were captured.


Each boat has 8 distinct images as well as other less distinct images.

From the boat track below we can see that there is quite some time between each individual image:

An aircraft in flight, such as the ones at the beginning of the post, is so fast that it will only be captured once and thus appears fainter than most of the other images we have featured above.

To see the locations featured in this post in Google Earth download this KML file. Be sure to turn on the 3D buildings layer to see the imagery.

The post Ghostly planes in Google Earth 3D imagery appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Classifying placemarks by region

jeu 25-02-2016

As we mentioned in yesterday’s post we have been working on a bit of code to determine whether or not a placemark lies inside a polygon. We believe we have got it working and thought it might be useful for people who want to classify placemarks by region. So, we have created the JavaScript-based tool below.

To use it, simply upload a set of placemarks and polygons and it will check what polygons the placemarks are in and put them all in folders named after the polygons and give you back a KML file with all the placemarks nicely categorised. As an example, we found this map of nuclear power plants on the Google Maps Gallery. We opened it in Google Earth to get the KML version, then used both it and the country borders we showed you yesterday to classify all the nuclear power stations by country.

It accepts multiple files so you can have your placemarks in one file and regions in another. It can be quite slow for large datasets. The above datasets took about 3 minutes on a fast computer.
[ Update: We have fixed a few bugs and added some optimizations which has improved the performance significantly.]

input,select{padding:4px;color:black;border:none}input[type="file"]{width:250px;}

Include empty regions

Classify placemarks

As usual we have not yet tested it thoroughly and make no guarantees that it will work perfectly. The country outlines are not very high resolution so placemarks near borders may be incorrectly classified. Let us know about any bugs you find or enhancements you would like to see, in the comments below.


Once the placemarks are classified it is easy to select only one folder.

We were also able to use it to make an approximate list of the number of nuclear power stations per country. Note that the list includes both active and inactive power stations and lists individual reactors not sites. For example Pickering in Canada has 8 reactors. We also do not know how old the list is.

The biggest problem is that nuclear reactors are often near coastlines and as mentioned above, the country outlines are not very high resolution and many of the nuclear reactors are outside the country borders. So, of the 766 reactors in the original file, only 578 were successfully classified.

#countryTable td ,#countryTable th { text-align: right } #countryTable th{vertical-align:initial;padding-left:14px;} #countryTable td:first-child ,#countryTable th:first-child { text-align: left;padding-left:0px; } #countryTable {font-size:10pt} Country # of reactors Armenia 2 Argentina 5 Australia 1 Bulgaria 5 Canada 24 China 22 Cuba 1 Czech Republic 9 Finland 2 France 71 Germany 32 Hungary 5 India 22 Iran (Islamic Republic of) 3 Israel 1 Italy 3 Iraq 1 Japan 45 Korea, Republic of 8 Lithuania 1 Slovakia 6 Mexico 1 Belgium 9 Netherlands 1 Romania 3 Russia 60 Slovenia 2 Spain 16 Sweden 9 Switzerland 11 Ukraine 22 United States 168 Taiwan 7

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Catégories: Sites Anglophones

Converting Shape files to KML with Google Earth Pro

mer 24-02-2016

We have been working on some code to determine whether or not a placemark lies inside or outside a polygon. We thought a nice use for that code would be to determine what country a placemark is in. For this we required the outlines of countries in KML format. We discovered ThematicMapping.org has a map of country outlines provided here. The Thematic Mapping API is a brilliant JavaScript API to help you create KML based thematic maps. See here for some of our previous posts about it.

The world country map is provided in what is known as the shapefile format. It is a popular format developed and maintained by Esri for use in GIS products. Google Earth Pro, it turns out, has built-in support for importing shape files. Simply go to File->Import then select “Esri Shape (*.shp)” from the file types list. Google Earth Pro then asks you if you want to apply a style template to the features you just ingested. We found that if we chose not to do so then all the shapes were named ‘[no-name]’. So, instead we chose to apply a style template which gives us the option to name the polygons from a field in a table of data included in the shapefile. One of the columns contains the country names, so we used that. There is also an option to colour the shapes based on a field in the data, all a single colour or random colours. We chose random colours. You can also set the icons and heights from fields in the data, but neither was appropriate in this case.


GEB reader Clare has noted that the map is a bit out of date with Sudan shown as a single country.

Once imported, if you click on one of the countries it shows a popup with some basic data about each country, such as name, area and population figures from 2005, which were contained in the shapefile. It is also now possible to save the dataset as a KML file. The resulting file is a little large, at 10.7MB, but compresses down to less than a third of that size when saved in the compressed KMZ format.

The original shapefile is shared under the Creative Commons ShareAlike licence, so you are free to use it on condition you give proper attribution to the original source. So, if you want some country outlines for use in Google Earth here is the KMZ version.

We have also created this version with all the extra country information removed, as well as changing the styles so as to only show country outlines.

The post Converting Shape files to KML with Google Earth Pro appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Celebrate Chinese Spring Festival in Google Earth

mar 23-02-2016

Here at GEB we have traditionally celebrated the new year with a Google Earth fireworks animation created by Steven Ho. This past new year we decided to expand on the idea by allowing you to create fireworks at the coordinates of your choice. This, in turn, has inspired Steven Ho to create a new animation to celebrate the Chinese Spring Festival, (also known as Chinese New Year or Lunar New Year).

His animation shows Chinese couplets falling from the sky, with the camera slowly rotating around the location you select – all set to music. Chinese couplets are a popular form of Chinese poetry that consists of a pair of lines of verse that match up in a number of different ways. You can learn a bit more about them on the Wikipedia page. They are popular for decorating doorways and also often used during celebrations, such as the Chinese Spring Festival.

He has also created a similar animation for the Taiwan Lantern Festival, which shows lanterns flying up into the sky at night.

To see YouTube videos of both animations and create animations for the location of your choice, see the full post on Steven’s blog.

The post Celebrate Chinese Spring Festival in Google Earth appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Google Earth 3D imagery progress

lun 22-02-2016

Google continues to push out new 3D imagery on a regular basis. However, an increasingly large proportion of it is updates to areas that already had 3D imagery. The updated areas are generally better quality and certainly welcome, but it does mean there is a noticeable decline in the amount of new area covered each month.


New area in square kilometres of 3D imagery covered by month. Note that we have not yet included all of the January and February, 2016 areas.

To see the area covered by 3D in Google Earth download our KML map.

We used to use the helpful online tool at Zonum Solutions to calculate the areas. However, it has a file size limit that our KML file has exceeded and a few other issues which make using it for our particular requirement quite tedious. So this time we used the area functions found in GeographicLib to do the calculations.

The US has almost double the area of 3D imagery of the rest of the world put together.

#countryTable td,#stateTable td ,#countryTable th,#stateTable th { text-align: right } #countryTable th,#stateTable th{vertical-align:initial;padding-left:14px;} #countryTable td:first-child ,#countryTable th:first-child,#stateTable td:first-child ,#stateTable th:first-child{ text-align: left;padding-left:0px; } #countryTable,#stateTable {font-size:10pt} Country Km2 Argentina 1,417 Australia 3,578 Austria 2,717 Belgium 2,511 Brazil 5,114 Bulgaria 1,946 Canada 13,145 Chile 1,146 China 158 Czech Republic 3,262 Denmark 1,326 Finland 860 France 22,012 Hungary 3,062 Germany 17,989 Greece 911 Ireland 197 Italy 19,799 Japan 14,069 Kosovo 82 Luxembourg 126 Malta 176 Mexico 4,614 Montenegro 81 Netherlands 294 New Zealand 706 Norway 4,641 Philippines 714 Poland 2,858 Portugal 5,455 Puerto Rico 638 Romania 2,518 Spain 17,690 South Africa 1,458 Sweden 1,285 Switzerland 4,043 United Kingdom 11,195 United States 325,290   US State Km2 Alabama 8,575 Alaska 580 Arizona 8,394 Arkansas 3,671 California 35,875 Connecticut 2,790 Colorado 6,321 Delaware 525 Florida 25,144 Georgia 12,730 Hawaii 956 Idaho 1,646 Illinois 6,698 Indiana 6,797 Iowa 3,718 Kansas 4,789 Kentucky 2,723 Louisiana 5,970 Massachusetts 7,610 Maine 1,968 Maryland 2,106 Michigan 10,192 Missouri 5,317 Minnesota 6,693 Mississippi 4,392 Montana 1,348 Nebraska 1,696 Nevada 2,244 New Hampshire 1,513 New Jersey 2,509 New Mexico 2,111 New York 11,895 North Carolina 14,638 North Dakota 1,106 Ohio 10,107 Oklahoma 3,872 Oregon 5,404 Pennsylvania 7,700 Rhode Island – Tennessee 10,400 Texas 27,524 South Carolina 9,405 South Dakota 796 Utah 4,594 Vermont 261 Virginia 7,348 Washington 9,166 Wisconsin 9,914 West Virginia 2,347 Wyoming 1,212

Note that some 3D areas overlap borders and the areas are recorded in the country/state where the bulk of the 3D lies. So Rhode Island State, for example, does have 3D imagery but it is part of a large area mostly in Massachusetts.

Thank you to all the GEB readers that find new areas and a special thanks to the GEB readers who draw new areas for inclusion in our map. New areas are noted in the comments of this post. If you wish to submit outlines please first read through the instructions found here.

The post Google Earth 3D imagery progress appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Fixing our circles

ven 19-02-2016

Earlier this week we posted a JavaScript tool for drawing circles in Google Earth. We noted that it didn’t seem to be accurate and assumed it was because some of the calculations were being done by approximating the Earth as a sphere.

Thank you to GEB reader DJ for trying it out and letting us know about a bug which resulted in this interesting pattern:

We decided to investigate and try and improve the accuracy of the code as well as fixing the above bug. We ended up finding a number of bugs. The first, is that for drawing circles, we had reused some code we wrote for drawing fireworks to celebrate the new year. The code correctly took into account the fact that latitude and longitude vary in scale, but apart from that used basic trigonometry to draw the circle. This works very well on small scales, but for very large circles problems become obvious, and if you draw a circle over one of the poles it wraps around it as seen below:

A second bug was due to the fact that in geodesic calculations there are two angles that are typically very similar and we were using the wrong one. This tends to only show up over large distances, so it is not something you notice immediately.

Finally, for the code to calculate intersections we decided to stop using the code from Movable-Type, which uses spherical geometry and instead used some code by Charles Karney posted here. The code was intended to be used with the C++ version of GeographicLib so we had to do some translation into JavaScript.

The result of the above corrections is still not perfect, but is certainly a lot more accurate than it was. There is still a bug that causes it to fail when the triangle is very large, but we hope to get that fixed over the weekend.

For those interested in the code:

Our code is written in the latest version of JavaScript, ES6, which works fine in Chrome, but we convert it to ES5 using Babel for greater cross-browser compatibility before using it on the site.

The post Fixing our circles appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Space Engine – to Infinity and Beyond

mer 17-02-2016

I still remember the first time I used Google Earth and how my sense of wonder grew as I realized the amazing capabilities of the program to portray our planet Earth at new levels of detail with a huge source of data both in aerial imagery, but also in 3D. It has been a long time since I found a program which generated the same sense of wonder. Until now.

Space Engine

I recently ran across an application called Space Engine which was reported to produce amazing visualizations of space and let you tour not only our solar system and nearby stars, but also stars throughout the Milky Way. Even better, the developer uses an algorithm to create planets, moons, asteroids and comets for as many star systems as astronomers currently believe exist, throughout our galaxy. Beyond that, Space Engine generates them for galaxies throughout the universe as we know it. So, you can literally visit trillions upon trillions of stars and planets (if you had enough time!) for endless galaxies. When you visit a planet, moon or asteroid’s surface, the program procedurally creates 3D terrain and textures to make the surface appear more realistic. To put this in perspective, this program lets you have an entire Universe to explore inside your own computer. Wow! However, it does require a relatively powerful desktop computer (or gaming laptop) with a beefy video card to run well (see the minimum specs in the download link at his web site).

My feeling was just as enthusiastic viewing Space Engine as the first time I saw Google Earth. What really amazed me was seeing the beauty of our universe when portrayed using more current graphics technology, and the endless sense of exploration to discover new worlds. Space Engine allows you to experience the awe and wonder of the Universe and capture your memories to share with others.

Space Engine uses data from dozens of astronomical databases to accurately portray the physical characteristics for all the known systems. It also extrapolates the characteristics for stars and planets beyond to fill our galaxy and other galaxies based on theoretical compositions. You can easily see the physical characteristics (size, mass, gravity, atmosphere, temperature extremes, and whether a planet could support life). In a sense it is more of a sandbox simulation, or a game, than a mirror of our universe.

It’s important to note that your movement in Space Engine isn’t limited by silly physical laws like the speed of light, so you are able to travel to other systems throughout the Universe in very reasonable amounts of time. If you were limited to our current technological and scientific abilities, and our understanding of physics (not being able to travel faster than the speed of light), it would take decades or centuries to even reach the nearest star systems to Earth.

I had plans for creating my own video demonstration of this application. But, I keep getting engrossed in the program. So, I’m sharing one of several YouTube videos about Space Engine to give you a taste of the experience. If you have dreamed of space flight, like I have, then you will most likely have the same reaction of awe and wonder that I do every time I use Space Engine. Watch this video demonstration by a gamer called Obsidian Ant who is just as amazed:

To make Space Engine more like a game, the developer has chosen to allow its users to add space ships and controls so you can fly through space as if you were an explorer and visit places. You can really get a sense of dimension when you compare objects next to a spaceship. The developer has even added support for virtual reality by supporting the Oculus Rift – so you can really immerse yourself in this universe.

Spacecraft near a moon

Like with Google Earth, Space Engine lets you click at a place (a star or other object you see in the background) and see information about it. Then, you can click a button and choose to simply fly to that location and get a closer view. Using various controls (including that Space Navigator, mouse, keyboard, joystick or even flight sim controls) you can easily move around the various astronomical objects and get better views. You can even land on them. I find myself regularly taking screenshots (like photographs) of the amazing views I see in this program! I have long used space art as a desktop background on my computers, and now I have an endless supply of views that are as good or better than those I’ve used before. If you search Google Images, you can find many thousands of screenshots from this program on the Internet.

Also like Google Earth, you can save a place you are viewing like a placemark and visit again at a later time, or share it with your friends. So, in many ways, Space Engine has abilities like Google Earth, but extrapolates its range to the whole universe, not just our home planet. But, Google Earth remains the king when it comes to portraying our home planet (both in terms of realism, but also in terms of the amount of data about Earth). Google Earth’s Mars and Moon modes also have far more data than Space Engine about those bodies. Space Engine has prettier views though, because it uses more recent graphics technologies and isn’t limited to near-surface viewing like Google Earth.

What’s really amazing about Space Engine, is that it was created, and continues to be developed, by a single person. Vladimir Romanyuk is a software engineer who lives in Russia. He has not only developed this application, but also architected his own universe using his knowledge of software and astrophysics. He does get help from an active community for space ship models, feedback, and contributions towards planetary models and textures. His software is not officially released yet – latest beta version is 0.9.7.4. But, judging by his fans, and my experiences, this freely available program is getting close to ready for broader use. According to his community forums he is planning to release a version of Space Engine for the Steam game platform soon which will greatly increase its exposure.

I should mention that there are some comparable commercial space games out there which already have a more robust gaming architecture for space travel with thousands of active users. The most popular and comparable one I’ve seen is Elite: Dangerous. Space Engine exists, in part, because of the much older pioneer in this genre of a free program called Celestia which also let you explore space and even allows people to create educational tours. I used Celestia many years ago as well and mentioned it in early days of Google Earth Blog posts, but the application has not been worked on for a long time. If you don’t have a fast enough computer for Space Engine, you can probably download and run Celestia (Windows, Mac, and Linux) and enjoy its more limited capabilities.

Many thanks to Vladimir for his fantastic work with Space Engine. He has done something I always thought would be the next step after Google Earth and even discussed with Google. I wish Vladimir the best success as he introduces his universe to a wider audience and continues to astound us with future features and data. His application right now is a real joy to experience. It may be a little tricky to learn the more advanced features, but the Space Engine forums can help you figure things out. Space Engine only runs on Windows right now, but he’s asking for donations to help him add new features and versions for Mac and Linux. He has recently uploaded his latest version to 0.9.7.4 RC1 (release candidate 1). Download here (note the file size shown on the page).

All of the screenshots in this post came from Space Engine with permission from it’s developer.

Purple Nebula Backdrop

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Catégories: Sites Anglophones

Drawing circles in Google Earth

mer 17-02-2016

In our recent post about LIGO and other large scientific instruments we mentioned that the Large Hadron Collider (LHC) at CERN in Geneva, Switzerland is underground. We know that it is circular and we were able to identify several buildings on its circumference. We would have liked to use that to draw a circle showing the location of the LHC. However, Google Earth does not have an option to draw circles. There are a number of tools on the web that will create a circle, given the coordinates of the centre and a radius, but in this case we don’t know where the centre is.

So, we thought it might be useful to have a tool that can draw a circle, given any three points on its circumference. It turned out to be more difficult than we expected, as trigonometry on the surface of the Earth is quite complicated. In two dimensions, the basic concept is easy; you just draw a triangle based on the three points, bisect the lines and where they intersect should be the centre. We used the same process but each of the steps has to be carried out using rather complicated formulas because of the curvature of the Earth. We used two different JavaScript libraries as we needed functionality from both. For distances and bearings we used GeographicLib, which is a popular open source library for geographic calculations. However, the current JavaScript version of GeographicLib does not include a method of finding the intersection of two geodesics so for that we used Geodesy from Movable-Type.

The results are not very accurate so if anyone knows a better algorithm for finding the centre of a circle on the surface of the Earth please let us know in the comments.


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To create a circle simply create a KML file with three placemarks, upload it below and click ‘Create Circle’.

Show calculations.

Create Circle

To create a circle that you know the centre of, create a placemark at the centre and name it ‘centre’ and create a second placemark on the circumference. Then upload it above and click ‘create circle’.

The post Drawing circles in Google Earth appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Radio Telescopes in Google Earth

mar 16-02-2016

Yesterday we had a look at some very large scientific instruments that can be seen in Google Earth. Today we are looking at telescopes. Optical telescopes come in sizes up to 10m in diameter, which is very large for an optical telescope, but not very large from the point of view of satellite imagery. Radio telescopes on the other hand, can be a lot larger.

The largest single dish radio telescope is the Arecibo Observatory in Puerto Rico with a diameter of 305 m.


Arecibo Observatory, Puerto Rico

China is building an even larger dish, the Five-hundred-meter Aperture Spherical Telescope (FAST) which, as the name suggests, will have a diameter of 500 m.


Five-hundred-meter Aperture Spherical Telescope (FAST), Guizhou Province, China

Large, movable dishes are also common. Below is the Effelsberg 100-m Radio Telescope.


Effelsberg 100-m Radio Telescope, Germany

Radio telescope arrays consist of a number of dishes spread out over a large area.

We start with the Giant Metrewave Radio Telescope in India. It consists of 30 separate dishes arranged in a ‘Y’ shape. Below we see the cluster of dishes at the centre of the ‘Y’.


Some of the dishes of the Giant Metrewave Radio Telescope

To see the whole ‘Y’ shape we have to zoom out to where the individual dishes are no-longer visible, so we have marked them with placemarks. It measures approximately 25 km between tips.


The layout of the Giant Metrewave Radio Telescope.

Next is the Karl G. Jansky Very Large Array (VLA), New Mexico. It is also in a ‘Y’ shape and has longer arms than the Giant Metrewave Radio Telescope above. Each arm has a railway line and the dishes can be moved along the arms to focus on different frequency ranges. Below you can see all the dishes have been brought to the centre. Be sure to check the historical imagery to see the dishes spread out all the way to the ends of the arms.


Karl G. Jansky Very Large Array (VLA), Plains of San Agustin, New Mexico.

The Square Kilometre Array stretches all the way from South Africa to Australia. The name refers to the total area of all the dishes in both countries once it is completed (one square kilometre). Below we see part of the South African site known as MeerKAT imaged in 2013. We could not find any actual dishes at MeerKAT but the foundations for dishes have been constructed. The image only shows the central part, so be sure to explore the site further in Google Earth. We have also identified the Australian site, which does have a lot of visible dishes that we have marked in the KML at the end of this post.


MeerKAT, South Africa

The Siberian Solar Radio Telescope consists of 256 dishes arranged in a cross:


The Siberian Solar Radio Telescope

Not all radio telescopes are dishes. There are a variety of other patterns, such as the Precision Array for Probing the Epoch of Reionization, which is located near the MeerKAT site in South Africa.


Precision Array for Probing the Epoch of Reionization, South Africa

The Low-Frequency Array for Radio astronomy (LOFAR) in the Netherlands has an interesting pattern. Below we see the central circle, but it extends quite a way outwards in an interesting pattern with sets of three dots. It can only be seen in ‘historical imagery’ because the default imagery is from 2005 before it was built.


Low-Frequency Array for Radio astronomy (LOFAR), the Netherlands

Another interesting design is the Nançay radio telescope in France.


Nançay radio telescope, France

To see the above locations, as well as a variety of other Radio Telescopes in Google Earth download this KML file.

The post Radio Telescopes in Google Earth appeared first on Google Earth Blog.

Catégories: Sites Anglophones

LIGO and other large scientific instruments in Google Earth

lun 15-02-2016

The biggest news in science recently is the detection of gravity waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo interferometer. You can learn more about it in this YouTube video. LIGO actually consists of two separate observatories in the US, and the Virgo interferometer is a single instrument in Italy. All three are ‘L’ shaped, with the two LIGO instruments measuring 4 km on each arm and Virgo measuring 3 km on each arm.


The LIGO detector in Washington State.


The LIGO detector near Livingston, Louisiana.


The Virgo interferometer, Italy.

Another similar instrument is GEO600, located near Sarstedt, Germany. It is quite a bit smaller, with arms 600 m long.


GEO600, Sarstedt, Germany

Another type of large scientific instrument is the particle accelerator. The most famous is the Large Hadron Collider (LHC) at CERN in Geneva, Switzerland. However, the LHC, like most other particle accelerators is underground and we can only identify a few related buildings on the surface. There are some particle accelerators that do have significant structures above ground, which you can see in Google Earth. Fermi National Accelerator Laboratory (Fermilab), in Illinois, has an accelerator known as the Trevatron, which has a circumference of 6.86 km. It is no longer operating.


The Trevatron particle accelerator.

Brookhaven National Laboratory on Long Island, New York has a number of different rings that can be seen:


1 The largest ring is the Relativistic Heavy Ion Collider.
2. The Alternating Gradient Synchrotron.
3. The National Synchrotron Light Source (circular building just to the right of the marker).
4. The National Synchrotron Light Source II.

Telescopes of various types are also highly visible scientific instruments but we will keep those for another post.

For the locations featured in this post download this KML file.

If you know of any other large scientific instruments clearly visible in Google Earth, let us know in the comments.

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Catégories: Sites Anglophones

Celebrate Valentine’s Day with Google Earth

ven 12-02-2016

This Sunday is Valentine’s Day. As we do each year we are sharing this collection of heart shapes to be found in Google Earth, which you can also see in this YouTube video. To add to that collection we found a few heart-shaped islands:

Clockwise from top left: 1. Galešnjak, Croatia, 2. Heart Reef, Great Barrier Reef, Australia, 3. Tavarua, Fiji, 4. Makepeace Island, Australia, 5. Anfi, Las Palmas, Spain, 6. Tung Talay Luang, Thailand.

You can view them in Google Earth with this KML file.

The largest known heart in the solar system is actually on Pluto and you can view it in Google Earth with this KML file.

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Catégories: Sites Anglophones