VZLUSAT-1

VZLUSAT-1 was a Czech technology demonstration satellite operated in low Earth orbit between 2017 and 2023 by the Prague-based company VZLU Aerospace. The 2U-type CubeSat was testing various spaceflight technologies including a miniaturized X-ray telescope and composite material radiation shielding. It was also performing scientific measurements of oxygen concentration in Earth atmosphere.^{[1][2][3][4][5][6][7][8]} The satellite was launched in June 2017 by the Indian PSLV-XL rocket,^[9] operated successfully in space^[10][11] for almost six years and more than 33,000 orbits, and ended its mission with destructive re-entry in June 2023.^[12] At that time, it was the longest operating Czech satellite to date and the second longest operating 2U CubeSat ever.^{[13][14][15][16][17]}