The advent of such high resolution civilian remote sensors has moved remote sensing close to the capabilities once reserved exclusively for military surveillance systems (see Page Intro 26e). Over the years, military and intelligence monitoring of sensitive targets from air and space has consumed much more resources (i.e., currencies) than civilian programs. Spy satellites, either deactivated now or in current operation, have had a significant, but seemingly indirect, impact to civilian earth- and space-observing systems. Their principal contribution, or driving force, has been development of technologies (directed towards high resolution) that, in recent years, have been declassified to an extent that civilian systems can now incorporate some of the improvement capabilities (these developments had been undertaken independently by NASA and other space agencies but until recently governments prohibited their use in operational systems).

The first major company to enter the marketplace with quality imagery is SPOT-Image (Systeme Probatoire d'Observation de la Terre), which is associated with CNES (Centre National dEtudes Spatiale). (Click here to examine SPOT's Internet home site.) This series of satellites has been launched on Ariane rockets from a base in French Guiana (northern South America). The headquarters and control center is in Toulouse, France. Formed in 1982, the organization has launched SPOT systems in 1986 (SPOT-1), 1990 (2), 1993 (3), 1998 (4), and, on May 3, 2002, SPOT-5. More on this program, including background on the sensors, on how SPOT produces stereo image pairs, and on applications, is found page 3-2. For now, we will show three images made by SPOT. The first shows the Rhone Valley in southern France where it enters the Mediterranean Sea, rendered in the SPOT multispectral mode (false color) at 20 meter resolution; the area covered is 50 x 50 kilometers.

Next is a 10 meter panchromatic image from SPOT-4 covering a part of Las Vegas, Nevada, one of the fastest growing cities in America.

This image is the first made by SPOT-5 (launched on May 3, 2002), showing the port of Eleusis in Greece, imaged at 2.5 m by the new HRG (High Resolution Geometric camera), which puts SPOT-Image in direct competition with other, newer companies that operate high resolution systems.

The panchromatic cameras on the SPOTs can be pointed off nadir to provide image pairs that are very effective in stereo viewing, as described on page 11-9.

SPOT is one of many higher resolution satellites that can, if clouds are few, provide useful imagery of the effects of disasters. The SPOT-2 image below was taken in October of 1986, less than five months after the nuclear power plant explosion at Chernobyl in the Ukraine. Visible is the extensive damage around Reactor 4:

One of the pioneers in commercial satellites is the Space Imaging Company (Denver, with offices in Europe and Asia). It was responsible for the IKONOS series of high resolution satellites. This link goes back to the original IKONOS gallery. As of January 2006, Space Imaging has become part of Orbital Imaging, Inc. (see below), with the combined companies (now the largest commercial satellite corporation in the world) being known as GeoEYE. The first in Space Imaging's IKONOS series failed during launch in April of 1999. The second IKONOS satellite was launched in September 1999 and has been operating successfully. Here is a panchromatic image of a part of downtown Washington, D.C., which can be further processed to attain 1 meter resolution. This image shows the Mall, the Ellipse, the White House, the Washington Monument, and many government and private buildings. But at the scale shown, individual automobiles are not resolved.

However, enlargement of a small part just southeast of the above IKONOS image shows the now realized potential of satellite imagery to disclose features, such as cars, approaching the full resolution of 1 meter. The circular building is the Hirshhorn Museum; the National Air and Space Museum and across the street, the building that once housed NASA, also appear.

Just outside the famed Washington "Beltway", in Greenbelt, MD, is the complex of buildings set in the forests of the Dept. of Agriculture's BARC (a 10000 acre experimental station) which is the home of the Goddard Space Flight Center (GSFC) - which includes Code 935, the Information Sciences Branch, the original sponsor of this Tutorial. It is also the NASA Center where the writer (NMS) worked for 21 years. Here is GSFC as seen first in an aerial oblique photo and then at 4 meter resolution by the IKONOS high resolution camera. The two buildings in the lower right in the space image are the home of the Earth Observations program and the Terra-EOS spacecraft personnel. Goddard is a lead center in Earth Observations, Meteorology, and Astronomy.

Goddard's chief "competitor" in remote sensing, in particular radar and infrared, is the Jet Propulsion Laboratory (JPL) in Pasadena, California (shown below). JPL is also heavily involved in Solar System exploration and, to a lesser extent, certain aspects of Astronomy. Many improvements and innovations in image processing and other aspects of remote sensing were developed at JPL, /primarily to support their Planetology program but also Earth applications. Shown here is a Google Earth (described below) view of JPL and an aerial oblique photos;

The ultimate in civilian remote sensing, for the present, is to achieve a resolution capable of seeing individual people from high orbital altitudes. IKONOS has achieved that - in this view of the famed Tiananmen Square in central Beijing, the scattered dots are actually native and foreign tourists moving about this heart of the capital city of China.

Space Imaging, Inc. has been a distributor for IRS (Indian Remote Sensing) Satellite imagery. With both panchromatic and multispectral sensors, IRS can produce color images with 4 meter resolution. This example of Kobe, Japan (some months after an earthquake there) shows the detail available with that system (disregard the yellow squares; these insets will not enlarge):

Another such recent high resolution commercial satellite is QuickBird 2, built by Ball Bros. and operated by Digital Globe (formerly known as EarthWatch), launched on October 18, 2001 into an orbit at 280 km. Its color imagery (an example from the Antarctic is shown on page 7-3) can achieve a resolution of 2.4 m (9 ft). Its black and white imagery attains a resolution of 0.65 m (2 ft). To set the stage for several Quickbird examples from southeast Asia, we will first look three lower resolution scenes, the first at a wide angle scene made by the MODIS sensor on Terra which covers most of Vietnam, Cambodia (note Mekong River), Thailand, and part of Malaysia. The greens denote the thick jungles that were such a difficult terrain in which to fight during the Vietnam War but observe that much of Thailand has been deforested (browns):

From this regional view, we will zero in on one of the great cities of Asia, Bangkok, in central Thailand. As a start let's look at an older photo taken from space by an astronaut. On the whole, it is not sharp or well color-balanced and rather dark. Until the last decade, astronaut photography was hit and miss, with many like the one below. Some pictures were excellent; many were tantallizing but unsatisfactory. Part of the problem in the earlier days was the ineffectiveness of filters in removing haze or atmospheric moisture degradation. (See Section 12 on Astronaut Photography for more details.)

From this next image, made by Terra's ASTER, you will like concur that this type of image is superior to the above astronaut photo in capturing information about Bangkok.

To further appreciate the value of high resolution space imagery, this next image (2 meter resolution) comes from the KVR-1000 photographic camera operating from the Russian SPIN-2 satellite (the photos taken are developed onboard, scanned digitally, and then sent as signals to a ground facility in southern Russia) The image covers part of central Bangkok:

The next pair of images, made by QuickBird, show a high resolution (4 meters) on top and then a very high resolution (1 meter) view of the city that contains the famed Royal Palace in Bangkok. Try to fit the bottom image into the top one:

Here is a photo of this Palace:

Just as we have seen with the IKONOS high resolution color imagery, Quickbird too produces stunning scenes. Compare the Quickbird scene of downtown San Francisco shown here with an almost identical coverage provided by IKONOS near the bottom of Page 6-9

And, consider this superb Quickbird-2 image of the Great Pyramid of Giza, southwest of Cairo. This imposing structure dates around 2600 B.C.

Quickbird-2 has, with its panchromatic scanner, obtained imagery with the highest resolution yet achieved (and allowed by national security interests): namely, 0.67 meters (about 2 feet). Digital Globe has released this example - a scene dominated by the giant Ferris wheel (115 meters high) in a Tokyo, Japan amusement park:

Quickbird has played a key role in "bringing satellite imagery to the general public"; this also serves to promote the benefits of remote sensing. Digital Globe has an arrangement with the search engine Google to provide images of almost anywhere on Earth to the television news rooms through its Google Earth service. When any such image appears on TV, look for the Digital Globe/Google Earth label on that scene. Now anyone can access these images. Users of Google can download a Google Earth program for free - or a more complete service by subscription. (One must have a Microsoft 2000 or newer operating system; 256 or more kbytes of RAM are also helpful.) One can recognize a Google Earth image by the distinctive information shown on the left and bottom sides, as in this example:

O-9: Where have you seen imagery like this? ANSWER

A panoply of imagery is available through Google Earth, ranging in scale from continents to individual buildings. These three images extend in scale from Europe down to Rome and to the Coliseum in that city (see also other Rome images on page 6-12).

During the July-August 2006 war between Israel and Hezbollah in Lebanon, Google Earth images were almost nightly occurrences on ABC, CBS, NBC, CNN and Fox news broadcast. As examples of what might be seen during this war, look at the next three images - the last a pair that show a "before" and "after" rendition of bombing damage to a Beirut neighborhood:

Space Imaging continues to launch satellites with high resolution. Worldview-1 was sent into space on September 18, 2007. Here is an image of downtown Houston, Texas, at 0.5 m resolution (unfortunately, the image was degraded when sized to fit the screen):

A third American company, Orbital Imaging Corp., Dulles, VA has so far launched OrbView-1, OrbView-2, and OrbView-3. This last satellite was placed in orbit by having its rocket booster dropped from an airplane and then ignited (this mode, launch from a ground rocket, and launch from the Space Shuttle are the principal methods used to insert satellites in Earth-circling orbits). This diagram shows the steps in this procedure:

Here is an example of an OrbView-2 image (2800 km wide), in near true color, that embraces a wide area of Pakistan and neighboring regions; note that a dust storm was in progress:

In January 2006, a major change occurred in the commercial satellite business when OrbImage purchased Space Imaging to form the largest company in the satellite remote sensing market. Their products are now sold under the name GeoEye; these products are purchased by Google, the U.S. Military, and foreign governments. Their website is currently sparse but permits entry into the old SpaceImaging and OrbImage sites. The company launched GeoEye-1 on September 6, 2008 as the first of its newest generation. The multispectral mode images have a resolution of 1.65 meters; the panchromatic images have a 48 cm resolution. Here is the first image released publicly:

Israel launched (from facilities in Russia) in December 5, 2000 its first commercial satellite dedicated to high resolution Earth observations. ImageSat International (ISI), established in 1997 and working with Israel Aircraft Industries and other companies, is now selling 1.8 meter (Standard) and 1.0 meter resolution panchromatic imagery from its EROS A1; this view of Izmir, Turkey is an example:

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A feature of the EROS A1 imagery is that stereo pairs are acquired. ImageSat had planned a follow-up EROS A2 but "scrubbed" this mission when the market for just panchromatic imagery proved a bit weak. They have now moved into the EROS B series which will have a 0.8 meter panchromatic sensor and a related system that will be multispectral. EROS B was successfully launched from Siberia on April 25, 2006. Here is one of the first images returned from that spacecraft:

Radar images made from orbiting spacecraft are also available for purchase. One of the earliest systems is Radarsat, launched in November 1994 and operated by the Canadian Space Agency. The commercial unit is RadarsatInternational (RSI). Radarsat utilizes the C-Band by itself to make its imagery. Below is an example of a Radarsat image; others are found on page 8-7. The scene shows the Dead Sea south of the Jordan River.

All these types of superior resolution satellites have both civilian and military applications. To illustrate what military surveillance can do, we look at two images now. The first involves aircraft reconnaissance over Cuba during the 1962 missile crisis:

Now, commercial systems can release 1 meter resolution imagery, giving details approaching "spy satellite" status. But for now, as an example of what civilian systems can do in reporting on a military system, we show here the image of the U.S. Navy EP-3 Reconnaissance aircraft on Hainan Island off the China coast where it was forced to make an emergency landing in late April, 2001 after a partial collision with a Chinese Jet fighter. The image was produced by Space Imaging Corp. using IKONOS 2 (altitude 680 km [about 420 miles]).

The third example shows an image of an Iraqi military facility during the 1991 Gulf War, using an optical scanning sensor on a U.S. Keynole (KH-11) satellite:

Military reconnaissance and/or direct attack is largely responsible for the rapid development of a new class of remote sensing platforms - the UAVs or Unmanned Aerial Vehicles. They fly sensors that operate in the visible and into the thermal infrared. These will be discussed in the page on Military Applications in the Introduction Section. For now, we show one prime example: the Reaper, which is operated remotely at a safe distance from the target (can be 100s to 1000s of kilometers away); this UAV in used primarily in the attack mode but also serves as an observer. (Note: UAVs also have civilian uses, such as search and rescue.)

As one might guess, nearly all UAV imagery taken for military purposes is classified. Here is a rare image made by the UAV Golden Hawk that shows the U.S. Navy's aircraft carrier Kitty Hawk:

Another military use is monitoring before and after effects of bombing during a war. The Second Iraq war (2003), waged by the U.S. and successful in toppling Saddam Husein, was well covered by satellite monitoring. This war was a direct consequence of a new approach to fighting terrorism that evolved after the attacks on September 11, 2001 (9/11) by Al Qaeda against targets in New York and Washington (see below). Here is a MODIS image of Baghdad and surrounding region in early April of 2003, showing the oil fires set as Coalition troops stormed into the city:

One of the SPOT-5 scenes has become very timely, indeed, as it shows the capital, Baghdad before it was attacked from the air. Below is a false color image of this city, cut into two halves by the Tigris River. A general map of Baghdad is reproduced beneath it:

Although it will undoubtedly slow down some of the viewers of this Tutorial who have minimal loading rates, we decided to show much of Baghdad in the high resolution (2 meters) image produced by Quickbird-2 (see below) as an example of the details available to both the military and the public during the war with Iraq in Spring of 2003. Scroll to see the full extent; use the above map to local key features:

As U.S., Britain, and other Coalition forces began to wage war with Iraq on March 19, 2003, both military and civilian (commercial) satellites having high resolution were daily observing much of that country with emphasis on places where weapons of mass destruction may be located. One group of prime targets are the many palaces of Saddam Hussein. The palace used for ceremonial and diplomatic activities is the (Old) Republican Palace on the Tigris. Here is an IKONOS satellite (see below) high resolution view of this complex:

Palaces, along with government and military buildings and facilities, have been prime targets during the cruise missile and aircraft bomb attacks from the outset of the war. Below is a IKONOS-2 natural color image (resolution = 0.9 meter) of central Baghdad acquired on April 1, 2003 that shows smoke plumes from bombardment during the previous night. Referring to the very large Quickbird image above, see if you can determine the target buildings involved.

O-10: Commercial satellite images are on the open market - available to anyone. That's the upside; can you think of a glaring downside? ANSWER

Through 2008 the allied coalition (mainly American troops) have maintained more than 125000 troops in Iraq. At times these forces had to endure great physical hardships as during regional, often severe dust storms such as that shown in this MODIS image:

Satellite imagery can sometimes be used to make a political statement. This is evident in this DMSP (Defense Meteorological Satellite Program) nighttime image of parts of China, Japan, and Korea. The white tones correspond to well-lit cities. The southern half of Korea, namely South Korea, is largely well-illuminated, a sign of a high level of prosperity. By contrast, North Korea is almost dark. Yet this is the "rogue" nation, which keeps its citizens in the dark, and has continuously threatened its neighbors and much of the world with its limited but dangerous nuclear capability. This is a classic example of an economically weak nation using its military power to achieve political gains.

DMSP imagery can be used in innovative ways. This next image shows western Europe and North Africa as though photographed from space (in fact, there are Internet sites that purport to claim this was taken by the Columbia astronauts soon before the spacecraft was destroyed). The image has been constructed digitally using DMSP data for the nighttime portion and MODIS data for the daylight portion. This results in a depiction of how the evening terminator might look from space:

Now, we consider three other examples of use of high resolution imagery that have both political and humanitarian overtones: Each illustrates the powerful use of these higher resolution satellites as a means for rapid monitoring of an area subjected to a human-caused or natural disaster.

The worst manmade catastrophe in American history took place on September 11, 2001 (now known simply as "9/11") when Al-Qaeda terrorists attacked New York City, the Pentagon outside Washington, and an aborted attack on the U.S. Capitol that ended in Pennsylvania. Here is a pre-attack photo of Lower Manhattan with the tall twin World Trade Center (WTC) buildings that became the prime target of the attack.

The role played by satellite surveillance was dramatically demonstrated by the imaging within two days of Lower Manhattan in New York City when the twin towers of the World Trade Center were destroyed by those terrorists using highjacked U.S. commercial airliners as "rockets" loaded with explosive jet fuel. The photos below has come to symbolize the worst moments before the WTC twin towers failed and collapsed to the ground:

The first space image of this catastrophe below was taken by the French SPOT-3 satellite just 3 hours after the first impact.

IKONOS-2 took the image below of Lower Manhattan nearly two years after 9/11, in which the changes around the "ground zero" area of the World Trade Center are evident. Even higher resolution IKONOS-2 images are presented on page 4-2, that includes a subsection which complements the treatment here of the 9/11 event in New York.

The WTC devastation has not just been imaged from satellites. Prior to Landsat and the now numerous earth-observing satellites that followed, users interested in vertical to oblique views of the surface relied chiefly on aerial photos (see Section 10). Here is a photo of Ground Zero for the 9/11 WTC attack taken from an airplane equipped with a mapping camera that flew overhead at an altitude of about 1000 meters (3000 ft).

Horrific as the 9/11 attacks against America have proved to be, they pale in comparison to the worst natural disaster to beset mankind in the last 100+ years. In the morning of December 26, 2004 a submarine earthquake of magnitude 9.3 took place off the northwest coast of Sumatra in Indonesia. Movement of the ocean floor was upwards which, in turn, heaved the column of overlying water into a huge mound at the surface. This generated outgoing waves, called tsunamis, that raced as speed up to 800 km/hr (500 mph) over the western Pacific and Indian oceans. When such waves reach shallow waters nearshore they transform into walls of onrushing waters up to 30-40 meters high and crash into beaches and inland for 100s of meters. This madly swirling water destroys buildings and drowns or sweeps living creatures caught in the maelstrom. This devastating tsunami sequence affected Sumatra, Thailand, India, Sri Lanka, and as far away as Somalia in Africa. The death toll may have exceeded 300000 people (many missing will never be found) - the worst such disaster in modern times. By sheer chance, the Quickbird satellite (see below), captured a view of a coastal town in Thailand that had been inundated by the initial tsunami and is about to be struck again by a later, smaller tsunami disturbance:

More on this disaster, as seen from space, is included on page page 3-7.

On January 2010, at about 5 PM EST, a magnitude 7.0 earthquake had an epicenter close to Haiti's capital city, Port-au-Prince, a population center of nearly 2 million. The devastation was major, with fatalities above 230,000. The country was ill-prepared to mount its own rescue operations, so aid from the U.S. and around the world has flowed in almost at once to rescue trapped victims, recover bodies, reduce the threat of disease, combat hunger, and start rebuilding. Satellites provided images of the scene within 24 hours. Here are a ground scene and two satellite images:

The three above examples show how effective satellite observations of disaster scenes are and how these images have become part of the routine for reporting such calamities. It was inevitable that a system for tracking lost or sinking ships, downed commercial aircraft, and individuals in need of help would be developed that uses satellites as a key component. In the early 1980s, NOAA, NASA, the Soviet and French space programs joined cooperatively in setting up the COSPAS-SARSAT system. (COSPAS is an acronym for Russian language words; SARSAT stands for Search and Rescue Satellite-aided Tracking). Background for the system is found at these two Internet sites: NOAA and Wikipedia. The essential idea behind the system is shown in this figure:

To date this system, and use of several other satellites, has been involved in more than 26000 calls for help and is credited with saving more than 3400 lives. One additional use is carried out by hikers who are lost or in need of medical help. If they have a transmitter, such as the one shown below, that sends a signal to a SAR satellite, their location is determined (much like the GPS system can pinpoint one's position) and rescue initiated.

The diverse images shown above are symbolic of the new benefits coming from the "great leap forward" in remote sensing, that is, the emergence in the 21st Century of private, commercial satellite operations rather than continued dependence on NASA/NOAA, space agencies in other countries, and the military to provide useful imagery of the planet we live and work on.

Another trend in satellites has been to put the same or complementary sensors on a group of satellites that work together to accomplish their mission. In some instances, this configuration is called "formation flying", in that several satellites are located or spaced in orbit such as to look at the Earth under different conditions (e.g., time of day) or with a higher frequency of coverage. In March, 2003, the first of a planned 4 ALSat satellites was launched successfully; the other three will follow later in the year. ALSat-1 is operated by Algeria When all are operating, they will allow any spot on Earth to be covered at least once in a 24-hour period (assuming suitable cloud[low] cover conditions). With wide area coverage at moderate resolutions (34 m under one mode), this will allow them to function as disaster monitoring systems. A fuller description of their capability is given on page I-23. Here is an ALSat-1 image of a 600 km wide scene extending from the Great Valley of California across southern Nevada into Utah:

And here is an ALSat-1 image of the desert in North Africa;

Satellites looking down on Earth are becoming commonplace. In fact, there are now more than 19000 satellites and fragments of disrupted satellites circling the Earth. So much so, that they constitute potential hazards for astronauts on board the Shuttle and to a lesser extent the International Space Station. Here are two plots of most of the intact satellites presently still orbiting our planet (note the band of denser black points - these are geostationary satellites):

But their persistent presence does not deter space agencies from continuous programs for future satellites. Launch schedules and hoped for life times are published routinely but these change routinely (usually delayed). Here is one such schedule diagram, applicable to the second half of the first decade of the 21st Century:

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Primary Author: Nicholas M. Short, Sr.

Collaborators: NASA GSFC, GST, USAF Academy