Context: Recently, NASA’s high-resolution air pollution monitoring instrument TEMPO was launched by the SpaceX Falcon 9 rocket from the Cape Canaveral Space Force Station in Florida.

• After this launch NASA has joined South Korea’s Geostationary Environment Monitoring Spectrometer and the European Space Agency’s Sentinel-4 satellite to become an air quality monitoring satellite constellation. 

About Tropospheric Emissions Monitoring of Pollution (TEMPO)

• It will measure pollution and air quality across greater North America on an hourly basis during the daytime, from Puerto Rico up to the tar sands of Canada.

• Its data will be used by agencies responsible for tackling atmospheric pollution.

• TEMPO will match the rotation of the Earth, meaning it will stay over North America all time.

Why is TEMPO so special?

• By monitoring the effects of everything from rush-hour traffic to pollution from forest fires and volcanoes, NASA data will help improve air quality across North America.

• It has smaller size (size of a washing machine) and has been described as a chemistry laboratory in space.

• It will be hosted on an Intelsat communications satellite in geostationary orbit.

• Existing pollution-monitoring satellites are in low Earth orbit, which means they can only provide observations once a day at a fixed time.

• TEMPO will be able to measure atmospheric pollution down to a spatial resolution of 4 square miles (10 square kilometers), or neighborhood level.

• It will have multiple applications from measuring levels of various pollutants to providing air quality forecasts and helping the development of emission-control strategies.

What is a geostationary orbit?

• It is a common orbit for weather satellites and communications satellites.

• Air quality instruments measuring gases hadn’t been there yet.

• Satellites in geostationary orbit (GEO) circle Earth above the equator from west to east.

• GEO is at an altitude of 35,786 km.

• They travel at the same rate as Earth.

• This makes satellites in GEO appear to be ‘stationary’ over a fixed position.

• GEO is used by satellites that need to stay constantly above one particular place over Earth, such as telecommunication satellites.

• This way, an antenna on Earth can be fixed to always stay pointed towards that satellite without moving.