Sample Google Earth navigation at low-resolution:

Quick links:

News:

4 March 2008

21 December 2007

11 December 2007

See here for older news.

 

The Pierre Auger Observatory is a very large array of detectors in Argentina, with plans for a similar array in the United States. Its aim is the study of the rarest and most energetic particles in the Universe: cosmic rays (most likely protons or bare atomic nuclei) at extremely high energies, whose origins are still a complete mystery despite decades of intense investigations worldwide. These cosmic rays can be studied indirectly by detecting the billions of high-energy particles they produce in interactions with the Earth's atmosphere. These come crashing down through the atmosphere in a cascade, or extensive air shower, that can be detected by counters scattered over a wide area, or else at night by detecting with sensitive telescopes the sky glow (nitrogen fluorescence) they produce in traveling through the atmosphere.

Physicists from 15 countries have been deploying detectors over an area of some 3000 km2 in western Mendoza province, Argentina, to detect these rare air showers (while planning to also deploy a similar array in the Northern Hemisphere in Colorado, USA). To this end, some 1600 surface detectors ("water Cherenkov counters") are being deployed, on a grid with 1.5 km spacing. On hills at the edges of the array, at four different sites, nitrogen fluorescence telescopes are built and operated on dark clear nights, working in coincidence with the ground array. Also near the center of the array are two central laser facilities, used to fire laser shots into the sky at night to calibrate the response of the nitrogen fluorescence detectors. Finally, an observatory campus is located in the town of Malargue, at the edge of the array, with a data acquisition and storage station, office building, and assembly building (where surface detectors are prepared prior to deployment in the field).

Because of the sheer scale of the project, it can be difficult to meaningfully explore the layout of the array and display the various detector components in a way that illustrates the distances involved. To help facilitate this exploration, a model of the Pierre Auger Observatory layout was constructed, to be viewed interactively using Google Earth. This allows the user to display the various detector elements, zoom in on them, tilt and rotate the field of view, etc. Running a Google Earth session requires a computer with reasonably high bandwidth access to the internet. Note that in parts of the map where Google Earth images are available at high resolution, Auger structures are not necessarily visible, depending on whether the Google Earth image (either from a satellite or aerial photo) was taken before or after deployment of the structure. There are currently two options:

Auger Google Earth Model

Auger Google Earth en Español

The Auger Google Earth model has been translated into Spanish, courtesy of Auger collaborator José Bellido. The file is: Observatorio_Pierre_Auger_Espanol.kmz ; this contains the final default positions of all surface detectors, some of which are not yet installed, but also the deployed surface detectors locations, as well as all 3D building models for the observatory.

Ignore any attempts by any browser uncompression utility to extract the individual files that comprise this archive. Note that some utility like WinZip might insist that it wants to save the file to a .zip file instead of .kmz . Force the extension to be .kmz so it will be recognized as a Google Earth object.

Auger Google Earth auf Deutsch

The Auger Google Earth model has been translated into German, courtesy of Auger collaborator Karl-Heinz Kampert. The file is: Pierre_Auger_Observatorium_Deutsch.kmz ; this contains the final default positions of all surface detectors, some of which are not yet installed, but also the deployed surface detectors locations, as well as all 3D building models for the observatory.

Ignore any attempts by any browser uncompression utility to extract the individual files that comprise this archive. Note that some utility like WinZip might insist that it wants to save the file to a .zip file instead of .kmz . Force the extension to be .kmz so it will be recognized as a Google Earth object.

Auger Google Earth in Italiano

The Auger Google Earth model has been translated into Italian, courtesy of Auger collaborator Daniela Maurizio and the students of her Class 4C of the Liceo Scientifico E. Majorana di Moncalieri (Torino). The file is: Osservatorio_Pierre_Auger_Italiano.kmz ; this contains the final default positions of all surface detectors, some of which are not yet installed, but also the deployed surface detectors locations, as well as all 3D building models for the observatory.

Ignore any attempts by any browser uncompression utility to extract the individual files that comprise this archive. Note that some utility like WinZip might insist that it wants to save the file to a .zip file instead of .kmz . Force the extension to be .kmz so it will be recognized as a Google Earth object.

Tour of Auger

The "tour feature" of Google Earth can be used to quickly and easily view the salient features of the Observatory without the need to master the Google Earth navigation interface. To do this:

Google Earth-based Event Display

The 3D nature of Google Earth navigation can be used to good advantage in displaying and exploring actual high-energy cosmic-ray events recorded by the Observatory. An example of such an event is shown in the following screenshot:

The hexagonal pyramids represent surface detector stations with activity, where the size/height of each pyramid is an indication of the activity in the corresponding detector. The yellow line is the reconstructed arrival direction in space of the air shower, and the blue and green triangles represent the fields of view of two nitrogen fluorescence detectors that recorded this event simultaneously. This was a stereo hybrid event ("stereo" because two fluorescence detectors recorded the event, "hybrid" because it was seen simultaneously with the fluorescence and surface detectors).

A library of 17 Auger sample hybrid events can be downloaded from the following file: Events.kmz . Ignore any attempts by any browser uncompression utility to extract the individual files that comprise this archive. Note that some utility like WinZip might insist that it wants to save the file to events.zip instead of .kmz . Force the extension to be .kmz so it will be recognized as a Google Earth object.

If you open up the folder "Events" you can select any of the 17 events for display by checking the box next to the event folder name. The event pictured above is event #9. If you open up the folder "GE event 9", say, you can turn on or off the surface detector signals and separately the nitrogen fluorescence detector signals. Note that event #15 was a "triocular" event (3 fluorescence detectors, or "eyes" saw the event simultaneously), while events #16 and #17 were "quadriocular" events (seen by all 4 eyes).

Movies of Google Earth Exploration of Auger

Fairly high resolution (1280x720) movies of a Google Earth based exploration of Auger are now available. The files here are very large (~185 MB), so they are not for the faint of bandwidth. All clips are in Windows Media (.WMV) format.

Two additional movies are now available:

Viewing Auger Events in Google Sky

With the newer versions of Google Earth (4.2 and up), it is possible to look up at the night sky instead of down at the Earth. Simply, from the Google Earth window, click on the small icon that looks like a planet above the main window (make sure the toolbar is visible; if not, make it visible from within the "View" menu at the top). In this Google Sky mode, you can now view the arrival directions of the most energetic Auger events (at energies beyond 57 EeV), with a 3.1 degree error circle surrounding each direction. Do this by downloading and opening the file Published_Auger_Events_Sky.kmz (remembering not to let the download utility rename the extension to .zip). You can see nearby Active Galactic Nuclei (AGNs), flagged by little sun symbols, that correlate well (within 4.8 degrees) with our event arrival directions, and could be sources of the highest-energy cosmic rays. The direction of Centaurus A, the nearest AGN to Earth, is particularly interesting, and layers are part of the model that show radio observations of the Centaurus A object by the Parkes and VLA radio observatories. A screenshot obtained with Google Sky appears below, showing the Centaurus A region.

Older News

6 December 2007

24 August 2007

1 May 2007

17 April 2007

 

Please send any comments or questions to Stephane Coutu . All 3D model files (done with the free Google SketchUp tool) are available on request.