Watch (Opens in a new window) Shop (Opens in a new window)
(Opens in a new window) (Opens in a new window)

Mission

The Traceable Radiometry Underpinning Terrestrial- and Helio-Studies, TRUTHS, mission would have been a ‘standards laboratory in space’, setting the ‘gold standard’ reference for climate measurements. With a cryogenic solar absolute radiometer and a hyperspectral imaging spectrometer as well as a novel onboard calibration system, TRUTHS would have made continuous measurements of incoming solar radiation and reflected radiation to evaluate Earth’s energy-in to energy-out ratio.


Update

The UK Space Agency led the mission, along with participation from other countries. However, at the end of 2025, the UK withdrew its funding, resulting in the suspension of development.


TRUTHS.png

Latest news

Explore
[ TRUTHS ]
TRUTHS: a standards laboratory in space
ARCHIVE CONTENT: 04 DEC. 2023

Contract secures next step for TRUTHS climate mission

Delegates from around 200 countries are convened at the United Nations COP28 summit in Dubai to assess the action they are taking to combat the climate crisis. With satellites fundamental to understanding and monitoring climate change, ESA has awarded a contract to Airbus to take the TRUTHS satellite mission to its next development phase.TRUTHS is set to provide the gold reference for climate measurements, thereby giving decision-makers more confidence in the data they use for climate action.
Read article
[ TRUTHS ]
Setting the gold standard for climate measurements
ARCHIVE CONTENT: 10 OCT. 2022

TRUTHS on the table at ESA’s Ministerial Council

With the satellite and instrument design consolidated and the scientific community assured it will deliver the data they need, TRUTHS has been approved as part of Earth Observation Programme proposal for the upcoming ESA Council Meeting at Ministerial Level. Carrying a primary International System of Units reference system, TRUTHS promises to set the gold standard for climate measurements.
Read article
[ TRUTHS ]
TRUTHS: a standards laboratory in space
ARCHIVE CONTENT: 20 JUL. 2022

TRUTHS shines

Satellites are essential for delivering key data to understand and monitor how the climate crisis is impacting our world, but, in turn, decision-makers need to be confident in the data they use for mitigation strategies and policymaking. TRUTHS, a new ESA mission, will do just this – and, now having passed an important milestone, it is one step closer to becoming a reality.
Read article
[ TRUTHS ]
Setting the gold standard for climate measurements
ARCHIVE CONTENT: 03 NOV. 2021

TRUTHS shapes up

ESA’s new TRUTHS mission is taking shape. Highlighted today at COP26, this new mission is moving from its feasibility phase into its preliminary design phase. TRUTHS is set to provide measurements of incoming solar radiation and of radiation reflected from Earth back out into space as traceable International System of Units. These measurements will allow changes in Earth’s climate to be detected faster, and they will be used to calibrate data from other satellites. In effect, TRUTHS will be a ‘standards laboratory in space’, setting the ‘gold standard’ for climate measurements.
Read article

Latest images

Explore
[ Earth Observation Programmes ]

TRUTHS

Play

Discover TRUTHS

[ TRUTHS ]
Setting the gold standard for climate measurements
29 OCT. 2021

A benchmark for climate data

The Traceable Radiometry Underpinning Terrestrial- and Helio-Studies mission, or TRUTHS for short, would have laid any such doubts to rest. The satellite, which ESA was building under the umbrella of ...
Read article
[ TRUTHS ]
TRUTHS: a standards laboratory in space
29 OCT. 2021

Facts and figures

UpdateThe UK Space Agency led the mission, along with participation from other countries. However, at the end of 2025, the UK withdrew its funding, resulting in the suspension of development. ...
Read article

Recommended

[ Directorates ]
Europe from space

Earth Observation Programmes

Only space provides the perspective to understand, monitor and act on our changing world.
Explore

We use cookies which are essential for you to access our website and/or to provide you with our services, enable you to share our website content via your social media accounts and allow us to measure and improve the performance of our website.

See our cookie notice