-A heliocentric model. That's right.

-A heliocentric model. That's right.

Movement of the planets, elliptical orbits, heliocentricity...

In other cases, the fact that the object is orbiting the Sun (heliocentric orbit) or is orbiting another planet is stated without any numerical values being provided.

We have gone from alchemy to chemistry, from a geocentric universe to a heliocentric, from believing that demons were the cause of illness to modern medicine.

For objects that are in heliocentric orbit, values in astronomical units (149,597,870 km: the approximate mean distance between the Earth and the Sun) are sometimes provided for the apogee and perigee.

The concept proposed was a space survey from a heliocentric orbit interior to that of Venus that would discover the most dangerous NEOs, the so-called Potentially Hazardous Objects, which are often the most difficult to detect from ground-based observatories due to the need to observe close to the horizon at small solar elongations;

With the use of multiple linear regression methods and on the basis of some 850 optical observations of comet C/1983 H1 (IRAS-Araki-Alcock), comet 55P (1995) Honda-Mrkos-Pajdusakova and comet 55P (1998) Tempel-Tuttle, as recorded in the International Comet Quarterly, the expressions characterizing the comets' heliocentric light curves and optimal adjustments at different phases of their trajectories were determined at IGA and it was established that the Delta effect could be seen during periods when the comets were at a distance of less than 0.3 astronomical unit from the Earth, thus making it possible to improve brightness predictions during those trajectory phases.