Dr. Gabi Sarosi - Chief Scientist at Alup company talks about the challenges facing the development of photography systems from space. Transcript of his lecture at the conference "Israel in Space - A View to the Future" held by the Hidan website and the Hamada Center on February 15, 2006
Alup is the largest electro-optics company in the State of Israel today. We produce all types of electro-optics, mainly for the military market. 95% of our products are security products, starting with small night vision goggles or a laser that the soldier holds at night. and including space cameras. Everything that the builders of the satellites and the launchers do is only intended to bring our camera into space and, as a result, also to bring the required intelligence.
I will concentrate on describing photography satellites. Basically all these satellites their purpose is to bring visual intelligence (Imaging Intelligence - IMIN) whether they are military satellites or whether they are civilian, their purpose is one - to bring intelligence. In the civil field, I want to bring intelligence about certain crops or areas infected with some kind of virus. or other areas where a disaster occurred and I want to bring intelligence from there and of course in military cases which are quite clear I want to bring intelligence from places I can't reach.
If we look at all the types of intelligence that exist today - the first is the old intelligence - human intelligence, the spies who come to the place we ask them to and they bring information from there. The second intelligence is signal intelligence (signal intelligene) - I pick up transmissions, whether it's someone talking to his friend on a cell phone or I pick up radar communications, and as a result deduce information. There is acoustic information - that I hear things, listen, I put microphones in all kinds of places. There is information that is the result of electromagnetic radiation. All of these are products of intelligence that has a certain level of certainty and a certain level of accuracy. The highest accuracy comes to us in the form of an image. When I have a picture I know exactly what is happening there, how it looks, where it is on the planet and therefore I have the most information.
The intelligence comes from cameras located in all kinds of places. For example a high mountain, we place a camera on Hermon to look into Syria. I can place a camera on a hot air balloon or on top of a plane flying at a high altitude and I can place a camera on top of a satellite.
One step forward is called Massing - MEASUREMENT INTELLIGENCE I perform physical measurements in the image that I can derive additional insights that I could not find in the image itself. I can look at an image and research each pixel in the image to see what its spectral depth is and as a result receive information that was not known to me solely from the two-dimensional image I took.
Aerial photography - I can extract information from the fact that a plane flies over the border at an altitude of 30 thousand feet and it looks deep into enemy territory and takes pictures diagonally. The way the TCA is done - by the fact that the plane flies, and it scans the area, it sweeps it in a lateral direction. As a result, I collect extracts that I electronically connect and get one long image.
Example, a photograph of Tel Aviv from a plane flying over Kiryat Gat and photographing the center of the State of Israel, you can see the chimneys of Hadera and the Palmach area. I can zoom in and go even further. You can see the beach of Tel Aviv from a plane flying over Kiryat Gat. The limitation of these images - that their range is relatively short. I can look at targets that are dozens of kilometers from the border, but what happens if a reactor is built in Iran, how do I photograph it?
Instead of risking airplanes to reach Iran, it is better to use space. The advantage of space - there is an international convention that there is no sovereignty in space. That's why we actually try to use satellite platforms to bring intelligence from faraway places.
We divide the projects into several parts - Ofek satellites for the Ministry of Defense, satellites that we developed for scientific missions such as UV satellites for deep space, satellites that we build for civilian commercial purposes - the Eros satellites and future plans.
Regarding the military satellites - two Ofek satellites have already flown into space - Ofek 3 and Ofek 5. Ofek 6 was launched and fell into the sea and since then it is said that the Navy finally got a satellite as well. Today they are working on the replacement of Ofek 6 which will be launched, I hope, soon.
Satellites for scientific purposes - several programs. Venus, a program in which the satellite is carried out by the aerospace industry and the satellite is carried out by El Op, a very prestigious program for the French space agency KENS in which Israel participates at the highest level.; The David satellite is a multispectral satellite, that is, the one that takes photos at several wavelengths. This satellite has not been launched yet but some of the components have already been produced; A fairly old project that should be launched soon is called Towax, a telescope that will look towards outer space in the ultraviolet regions at three wavelengths in this field and is supposed to investigate phenomena that occur in deep space. It will be launched on top of an Indian satellite. All this camera is seen on the Indian satellite as a hitchhiker. The satellite itself is a satellite supposed to do other things and we use it as a carrier to put this telescope. This is a geostationary satellite that will stay in space for many years. This is a project designed by Tel Aviv University under the leadership of Prof. Noah Brosh.
Commercial programs - there is an Eros program, a program we did for Korea - filming with several wave guests. Maros we sell the photos - for example, a certain municipality wants to check construction anomalies, they order a photo of the area, compare it to a photo taken a year before and see who built without permission.
The method in which the commercial satellites work - according to a plan in advance, I photograph selected areas as the customer orders. Another option - sometimes the customers don't want us to know what he is filming and give him command of the satellite and then he films what he wants. Of course, we do not give control over the State of Israel to anyone. The factors we work with are also factors for which we have a permit from the Ministry of Defense, even though the satellite is a civilian satellite, and this is also monitored. The Eros A satellite photographs with a resolution of 1.8 meters, while the Eros -B will photograph with a resolution of 0.7 meters, which ten years ago was a resolution for the security sector. Today this is a suitable resolution for the civilian market.
Another project is a multispectral satellite for South Korea - a joint program between us and the Korean Ministry of Science. This satellite should be launched this May. The satellite is assembled in-house and tested in integration with its entire launch system in Korea. Examples of photos from the Eros satellite, in this case - Eros A you see Beijing - the Forbidden City and Tien An Men Square. The black dots in the square are people. Other examples - Cape Town, the collapse of a volcano in Papua New Guinea. Abu Dhabi area, lots of stadiums. And this is a civil resolution.
Infrastructure - these cameras are very high resolution cameras. We are in Metula and we see the windows of the Dan Hotel in Eilat. In order to reach these capabilities, the cameras themselves are special cameras, which have a very large optical key in order to collect as much energy as possible and obtain a high resolution. As a result we throw all the light received by the large telescopes onto the sensors. The amount of elements in each sensor is high and this is what allows us the high resolution.
Inside El Op there is a huge hall inside which the cameras are assembled. They have a huge vacuum chamber that can fit dozens of people. When the satellite needs to be checked, the air is removed and the satellite's durability is tested in space conditions - vacuum, temperature differences, etc. In order to prevent malfunctions, we do preliminary tests in the special chamber. In this way, we make sure that when the satellite arrives in space after all the launch vibrations, it will be able to withstand the conditions of space and perform for years what we ask it to do.
Another example of infrastructure - to raise the weight into space the price is equal to the weight in gold. We design huge but very light mirrors in order to enable the high optical efficiency without weight.
I have ten thousand detectors. While the satellite is moving, I perform an exposure and capture, I photograph every meter of the satellite's surface in the detector vector. The scanning is carried out by the very movement of the satellite itself. I get a lot of lines and connect them together. In this way I collect a long image which is the path the satellite makes during its movement, in microseconds.
The future is satellite systems that will see both day and night, the story of the SAR is not over yet, so the idea is to go for satellites that take photos in both visible light and infrared, and in general to go for multispectral satellites, so we can get more information. Hyper-spectral sensing - looking at each pixel and checking its spectral data. Therefore we can also know what the spectral signature of materials that are on the ground is, as a result we have additional information that we do not see in the two-dimensional image.
For example, I want to identify areas in the ocean that have a high concentration of plankton, to send the fishermen there because the fish will come there or to look for certain minerals. An example of test flights we carry out in Israel with a hyperspectral camera. For example, we did an experiment over the Kinneret - we mapped the chlorophyll in the water, we know how many milligrams per cubic meter there are in the eastern part of the Kinneret. The chimneys of the power plant in Ashdod emit carbon into the atmosphere and you can see the carbon concentrations on the roofs of the houses. In Ramat Hovav - we flew over Ramat Hovav, we see the bromine cloud that is above Ramat Hovav. I'm looking for the bromine, know what his signature is. In a normal picture it looks like the air is clean but when you look at it with a hyperspectral camera you see the whole jeep.
Question from the audience - why are the pictures from Eros in black and white? Dr. Serosi's answer: "We prefer resolution over color. In a color image, each pixel consists of three points - red, blue and green (RGB). I win the color part but wasted 3 pixels of resolution for every pixel of color.
