Earth Venture Instruments: fit a measurement to a host

Earth Venture Instruments, EVI, is a documented selection lineage within NASA’s Earth Venture work managed through ESSP. Its focus is developing scientific instruments for flight opportunities rather than requiring every investigation to build its own complete spacecraft. The historical class name does not mean that all Earth-science instruments belong to EVI, or that every future solicitation must preserve the same categories.

NASA selected TEMPO as the first EVI award in 2012. The instrument investigates air pollution through ultraviolet and visible observations. This is a focused question about atmospheric composition, distinct from providing ordinary telecommunications. A hosted scientific instrument can share a platform with another mission while keeping its own measurement goals and scientific responsibilities.

TEMPO flew in April 2023 aboard the commercial Intelsat 40e satellite. Intelsat 40e is its host spacecraft, and Falcon 9 was the launch vehicle. These names describe three roles in one arrangement. The instrument needs a suitable view, stable pointing, power, thermal conditions and a route for transmitting its observations; a physical mounting location alone is not enough.

A fictional host might offer sufficient power but regularly point away from the required scene. That would threaten the scientific objective even though the electrical connection works. Interface design links the investigator’s measurement requirements with the host operator’s constraints. Agreements and tests must establish when and how the instrument can observe and return data.

Hosted science needs compatible services

TEMPO’s geostationary vantage supports repeated daytime observations over North America. Its changing pollution maps can help investigate variation across the day, rather than treating one daily snapshot as the whole story. The measurements require suitable sunlight and retrieval methods; a map of an atmospheric column is not automatically a direct measurement of the air a person breathes at ground level.

Consider a fictional city with different patterns in morning and afternoon observations. To interpret that difference, examine clouds, winds, sunlight and retrieval quality as well as emissions. A hosted instrument makes a particular observing opportunity possible; careful science determines what its signals support. EVI illustrates how choosing a compatible platform can enable a focused measurement without duplicating an entire spacecraft development effort.