An image processing device provided at a ground station connected to a network, comprising: an estimated altitude acquisition unit for acquiring an estimated altitude of a flying object (16, 26, 40, 234, 334, 800) from a communication equipment on the network; an adjustment control unit for causing a distance between a first flight vehicle and a second flight vehicle to be adjusted depending on the estimated altitude; an image acquisition unit (232, 332) for acquiring: a first image including, as a subject, a first region captured by a first camera which is mounted on a first flight vehicle as a stratospheric platform and which captures an image from a first altitude toward a direction of an altitude lower than the first altitude, and a second image including, as a subject, the first region captured by a second camera which is mounted on a second flight vehicle as a stratospheric platform and which captures an image from a second altitude toward a direction of an altitude lower than the second altitude, wherein a shooting time of the first image is the same as a shooting time of the second image; and a flying object (16, 26, 40, 234, 334, 800) detection unit for detecting the flying object (16, 26, 40, 234, 334, 800) at an altitude lower than the first altitude and the second altitude, based on a difference between the first region in the first image and the first region in the second image; and wherein the image acquisition unit (232, 332) is further configured to: receive the first image that was transmitted from the first flight vehicle to the ground station and receive, via the network, the second image that was transmitted from the second flight vehicle to another ground station; and the adjustment control unit is configured to transmit flight control data of the first flight vehicle to the first flight vehicle from the ground station and to transmit flight control data of the second flight vehicle to the second flight vehicle via the network. an estimated altitude acquisition unit for acquiring an estimated altitude of a flying object (16, 26, 40, 234, 334, 800) from a communication equipment on the network; an adjustment control unit for causing a distance between a first flight vehicle and a second flight vehicle to be adjusted depending on the estimated altitude; an image acquisition unit (232, 332) for acquiring: a first image including, as a subject, a first region captured by a first camera which is mounted on a first flight vehicle as a stratospheric platform and which captures an image from a first altitude toward a direction of an altitude lower than the first altitude, and a second image including, as a subject, the first region captured by a second camera which is mounted on a second flight vehicle as a stratospheric platform and which captures an image from a second altitude toward a direction of an altitude lower than the second altitude, wherein a shooting time of the first image is the same as a shooting time of the second image; and a first image including, as a subject, a first region captured by a first camera which is mounted on a first flight vehicle as a stratospheric platform and which captures an image from a first altitude toward a direction of an altitude lower than the first altitude, and a second image including, as a subject, the first region captured by a second camera which is mounted on a second flight vehicle as a stratospheric platform and which captures an image from a second altitude toward a direction of an altitude lower than the second altitude, wherein a shooting time of the first image is the same as a shooting time of the second image; and a flying object (16, 26, 40, 234, 334, 800) detection unit for detecting the flying object (16, 26, 40, 234, 334, 800) at an altitude lower than the first altitude and the second altitude, based on a difference between the first region in the first image and the first region in the second image; and wherein the image acquisition unit (232, 332) is further configured to: receive the first image that was transmitted from the first flight vehicle to the ground station and receive, via the network, the second image that was transmitted from the second flight vehicle to another ground station; and the adjustment control unit is configured to transmit flight control data of the first flight vehicle to the first flight vehicle from the ground station and to transmit flight control data of the second flight vehicle to the second flight vehicle via the network.