Image Dataset taken by 1U CubeSat Constellation in the Low Earth Orbit

This dataset contains images taken by four 1U CubeSats (3 satellites from BIRDS-3 and 1 satellite from BIRDS-4) that belong to the BIRDS Constellation of satellites. The camera mission payload employs a single 5-megapixel (MP) OV Arducam module, 8-bit Atmega2560V MCU, and 1Gb MT25QL01GB as non-volatile flash storage. Images are available at different resolutions such as 1280 x 960, 640 x 480, and 320 x 240.
A commercial S-mount, M12 lens from Lensation was used for optics, however, BIRDS-3 and BIRDS-4 used different specifications. For BIRDS-3, the lens has a focal length of 2.9mm and an f2.0 aperture providing a diagonal field of view (DFOV) of 103º. The ground swath calculated from a 400 km orbit is about 700 km by 450 km. For BIRDS-4, the lens has a focal length of ¼ inch and an f1.8 aperture providing a diagonal field of view (DFOV) of 125º. The ground swath calculated from a 400 km orbit is about 800 km by 600 km.
The CubeSats were deployed from International Space Station (ISS) into an orbit of altitude 400 km, inclination of 51.6°, and orbital duration of 92.6 minutes. The satellites do not have any attitude control, so the satellites are in free rotation at approximately 3 deg/s on each axis.
The dataset contains 156 images from the BIRDS-3 constellation of satellites and 81 images from the BIRDS-4 satellite. The images have been named according to their resolution and basic classification into Earth images (ER), Horizon images (HZ), sunburn images (SB) and space images (SP). The images are unprocessed, raw images and the sizes of the images vary between 3kB for space images and up to 99kB for earth images.

本数据集收录了四颗1U立方星（其中BIRDS-3星座3颗卫星及BIRDS-4星座1颗卫星）所拍摄的图像。该相机任务的有效载荷采用单枚5百万像素（MP）的OV Arducam模块、8位Atmega2560V微控制器单元（MCU）以及1吉比特MT25QL01GB作为非易失性闪存存储。图像提供多种分辨率，包括1280 x 960、640 x 480以及320 x 240等。光学系统采用了Lensation公司生产的商业S型M12镜头，BIRDS-3和BIRDS-4分别采用了不同的规格。对于BIRDS-3，镜头的焦距为2.9毫米，光圈为f2.0，提供103°的对角视野（DFOV），从400公里高度的轨道计算得出的地面带状区域约为700公里 x 450公里。对于BIRDS-4，镜头的焦距为1/4英寸，光圈为f1.8，提供125°的对角视野（DFOV），从400公里高度的轨道计算得出的地面带状区域约为800公里 x 600公里。

立方星是从国际空间站（ISS）部署至海拔400公里、倾角51.6°、轨道周期92.6分钟的轨道。由于卫星不具备姿态控制，因此卫星在各个轴向上以大约3度/秒的速度自由旋转。

数据集中包含来自BIRDS-3星座的156幅图像以及来自BIRDS-4卫星的81幅图像。这些图像根据其分辨率以及基本分类（地球图像（ER）、地平线图像（HZ）、日烧图像（SB）和太空图像（SP））进行命名。图像为未经处理的原始图像，图像大小介于3kB的太空图像到99kB的地球图像之间。