ESA’s oldest Earth-observer images Delhi airport

Plentiful parked airliners at Indira Gandhi International Airport in New Delhi, usually the busiest airport in India until the COVID-19 pandemic, as seen by ESA’s oldest operational Earth observation mission, Proba-1.

The cubic-metre-sized satellite has been in orbit for more than 18 years. It left Earth from India: Proba-1 was launched from the country’s Satish Dhawan Space Centre by Polar Satellite Launch Vehicle on 22 October 2001.

The first in ESA’s family of ‘Project for On-Board Autonomy’ missions, Proba-1 began life as a technology demonstration satellite, subsequently becoming an Earth observation mission. Its main hyperspectral Compact High Resolution Imaging Spectrometer is accompanied by the monochromatic High Resolution Camera, which took the 5-m spatial resolution image shown here.

Overseen from ESA’s ESEC-Redu centre in Belgium, the highly-automated Proba-1 introduced various then-novel but now mainstream technologies to space, including lithium ion batteries, gallium arsenide solar panels, the use of startrackers for gyro-free attitude control and ESA-developed ERC-32 microprocessors running its flight computer.

Proba-1 continues to deliver imagery to scientific teams around the globe, while also providing useful data on the longevity of space systems and components.

Proba-1 was followed by the Sun-observing Proba-2 in 2009 and vegetation-tracking Proba-V in 2013, with the double-satellite Proba-3 to demonstrate precision formation flying while studying the Sun’s corona planned for launch in 2022.

This 25 sq. km HRC image was acquired on 7 May 2020.