# Recommendation

The availability of precise brightness models for planets makes the original implementation in ASTRO obsolete.

We propose to update ASTRO using recent models for giant planets and Mars, the most commonly used planets in the framework of flux calibration of IRAM observatories.

We will use state-of-the-art models developped by experts of planetary science and radio astronomy and already used for the calibration of world-class facilities like Herschel, ALMA, or the EHT.

After the update, the planet fluxes as computed by ASTRO will be significantly different than the ones used before, especially at low frequencies.

To avoid confusion and make sure the most precise models are used, the 2024 scheme will replace the original one. If some users want to make a comparison of the Legacy vs 2024 results, they will have to use different gildas releases.

The update will be done in two steps: 1st the giant planets, then Mars, once the integration of the full physical model in ASTRO will be ready.