CHINESE SATELLITES-DRO-A & DRO-B (Syllabus: GS Paper 3 – S&T)

Context: A pair of Chinese satellites (DRO-A and DRO-B) failed to reach a planned orbit on their way to the moon after experiencing abnormalities, a rare setback for Beijing's high-profile space program.

About DRO-A and DRO-B:

• Launched from: Xichang Satellite Launch Centre in the Sichuan Province.
• Launched by: A Yuanzheng-1S (Expedition-1S) upper-stage aircraft.
• Aim: The plan was for the two satellites to head towards the moon and enter a distant retrograde orbit (DRO).

oFrom there, they would fly in formation and work with DRO-L - a third satellite that was successfully placed into low-Earth orbit by a Jielong 3 rocket last month - to test laser-based navigation technologies between the Earth and the moon, known as cislunar space.

o

Distant retrograde orbit (DRO):

• About: The DRO orbit is at a high altitude, tens of thousands of kilometres above the lunar surface.

oIt is highly stable, allowing spacecraft to remain on track for a long time without using fuel, and is an advantageous waypoint for research and exploration.