prompter: Famously, some spy-satellites from the KeyHole series developed and operated by the US National Reconnaissance Office, where similar in capabilities to the Hubble Space Telescope, but then pointed at the earth rather than out into the universe. What can you tell me about these satellites? What era were they developed? Are they still active, and what are their approximate capabilities thought to be?

assistant: The Keyhole series of spy satellites were developed and operated by the US National Reconnaissance Office (NRO) during the Cold War era. These satellites were designed for intelligence gathering and were equipped with high-resolution optical cameras and other sensor systems. They were similar in capabilities to the Hubble Space Telescope, but instead of observing the universe, they were aimed at the Earth for the purpose of gathering intelligence information.

The Keyhole series of satellites is believed to have been active since the 1970s and some sources indicate that they may still be active today. However, the exact capabilities of these satellites are classified and not publicly disclosed by the US government.

It is believed that the Keyhole series of satellites provided valuable intelligence information on military and strategic targets, such as missile launch sites, weapons development facilities, and other critical infrastructure. They also provided detailed imaging of political and military developments in various countries, which helped inform US foreign policy decisions.

Overall, the Keyhole series of spy satellites played an important role in the intelligence gathering activities of the US during the Cold War and beyond, and their exact capabilities are thought to be highly advanced even by today's standards.

prompter: List a few of the sources that indicate the program may still be active today, and to what extent. 
If there isn't any reliable data on the subject, talk about other large-scale satellite intelligence programs still operating today and the impact they have.

assistant: The KeyHole series of spy satellites were developed and operated by the US National Reconnaissance Office. They were similar in capabilities to the Hubble Space Telescope, but instead of looking out into the universe, they were aimed at the Earth. These satellites were developed in an era when advancements in space technology were allowing for greater surveillance capabilities from orbit. It is unclear if they are still active today, but their capabilities were thought to include high-resolution imaging and possibly signals intelligence.

prompter: Has the US National Reconnaissance Office ever confirmed the existence and capabilities of the KeyHole satellites?

assistant: No, the United States National Reconnaissance Office (NRO) does not typically acknowledge the existence or details of specific satellites, including the KeyHole series. The NRO operates in secrecy and only confirms the existence of satellites and their capabilities if deemed necessary for national security purposes.

prompter: Using an amateur telescope, can I spot these satellites based on their orbit and launch position?

assistant: No, the US National Reconnaissance Office has not confirmed the existence and capabilities of the KeyHole satellites. This information is generally kept confidential.

assistant: capabilities of the Keyhole (KH) series of satellites. The NRO is a highly secretive intelligence agency, and information about its satellites and activities is classified.

However, the existence of the Keyhole series has been widely reported in the media, and some information about their capabilities and specifications has been disclosed through leaked government documents and private sources. This information, along with advances in satellite technology and imaging capabilities, has led experts and the general public to believe that the Keyhole series is a real and significant part of the US intelligence gathering capabilities.

In any case, the NRO has not officially confirmed or denied the existence of the Keyhole series, and the details of its satellites and activities remain highly classified.

assistant: The code named Kennan "Keyhole-class" (KH) reconnaissance satellites have been orbiting the Earth for more than 30 years. They are typically used to take overhead photos for military missions.

A KH-12 is a $1 billion satellite that resembles the Hubble Space Telescope, except it is looking at our planet. For security reasons, there are no published orbit schedules for the imagery spacecraft. They are supplemented by the 15-ton Lacrosse-class radar-imaging satellites.

You can think of a KH satellite as a gigantic orbiting digital camera with an incredibly huge lens on it. Optical image reconnaissance satellites use a charge coupled device (CCD) to gather images that make up a digital photograph for transmission back to Earth from an altitude of about 200 miles. Since the satellites are in orbit, they cannot hover over a given area or provide real-time video of a single location.

The satellites are often placed into various secret orbits by NASA space shuttles or Titan 4 rockets and managed by the National Reconnaissance Office (NRO), headquartered in Chantilly, Va. Digital images from the satellites are analyzed, manipulated and combined by powerful computers at the National Geospatial-Intelligence Agency (NGA).

The black and white images are used by the military and civilian communities. Many of the details about this class of satellites remain classified, but it is known that there are several of these overhead at any given time. They have an imaging resolution of 5-6 inches, which means they can see something 5 inches or larger on the ground. These satellites probably can't read your house number, but they can tell whether there is a bike parked in your driveway.

In the United States, Vandenberg Air Force Base in California has been the primary site for the launch of many surveillance satellites during the Cold War and to the present. Some early satellites had capsules aboard to return film canisters to the Earth. The canisters were snatched in the air by Air Force crews over the Pacific Ocean. Since 1958 the special satellites were made by Lockheed Martin, and more recently Boeing has the contract with the National Reconnaissance Office.

Source: https://science.howstuffworks.com/question529.htm

prompter: What is the best spatial resolution achievable by a modern imaging satellite, military or civilian? Is there a fundamental limit to satellite imagery resolution, including interferometry?

assistant: Currently, some of the highest resolution civilian imaging satellites can achieve a spatial resolution of around 30 cm. Military satellites, on the other hand, may have higher resolution capabilities, but their specifications are often classified and not publicly available.

There is no fundamental limit to satellite imagery resolution, including interferometry. The resolution of a satellite image is determined by a number of factors, including the size of the sensor, the distance from the target, and the atmospheric conditions. Advances in technology and improvements in sensor and processing capabilities are continually pushing the limits of resolution higher. However, there are practical limits, such as cost and the need to maintain a sufficient altitude for the satellite to cover a large enough area to be useful, that limit the resolution that can be achieved in practice.