Geocentricism is NOT a Church teaching and Catholics do NOT have to believe it.
thistle, let me give you a fair answer to this profound question. In essence, geocentricism IS a defined and declared papal decision. This was confirmed by the Church twice, in 1633 and 1820. It was declared as formal heresy.
But this heresy was different. It was chosen by the Devil because it was different. The heresy came under the following principle:
‘. Nor may it be answered that this is not a matter of faith, for if it is not a matter of faith from the point of view of the subject matter (ex parte objecti), it is a matter of faith on the part of the ones who have spoken (ex parte dicentis). It would be just as heretical to deny that Abraham had two sons and Jacob twelve, as it would be to deny the virgin birth of Christ, for both are declared by the Holy Ghost through the mouths of the prophets and apostles.’
Because of these double edged conditions, probably the only one of its kind in the history of the Church, it was not contradictable on faith, but open to contradiction in its subject matter. It was this that led to the crisis from 1741 to 1835. Alas, Churchmen fell for the fraud that Heliocentricism was proven so the crisis became very serious indeed.
Now there are two way such legislation can be interferred with, it can be abrogated or derogated.
(A) Abrogate it; that is, abolish it completely. But for a law to be abrogated, new legislation must accompany it, stating this clearly, and in justice should state why this is being done.
(B) A judgment of a previous pope can be derogated. This means that the legislation still remains in force but it has been modified in some way.
Now this presented the Church of 1741 and 1820 with an impossible decision. Because it was a papal definition and declaration it was immutable, but this one was perceived to be a false one. But even in its chaos the Holy Ghost was still protecting the Church with its divine guidance. In the end that Churchmen involved derogated the decree out of sight. This they had the divine power to do. But they had no power to abrogate the decree without admitting to an original error. The crisis was avoided when:
Finoccchiaro records the outcome of it all.
‘On December first, 1820, the Inquisition consultant discussed Olivieri’s answers and decided to request the opinion of two other experts, B. Garofalo and Bartolomeo Capellari (who would later be elected Pope Gregory XVI). At this point the documentary trail is lost. But not the historical connection. For on 20 May 1833, while deliberating on a new proposed edition of the Index, Pope Gregory XVI decided that it would omit the five books by Galileo, Copernicus, Kepler, Foscarini and Zúñiga, but that this omission would be made without explicit comment. Thus the 1835 edition of the Index for the first time omitted from the list Galileo’s Dialogue, as well as the other books.’ — Retrying Galileo, p.198.
‘Without explicit comment’! Again we see the Holy Ghost at work, there being no attempt to deny an ‘irreversible’ papal decree. ‘Hell’ Christ promised, ‘would not prevail against the Church’, and here is evidence to prove that divine protection. While His elect were insisting Copernicanism was orthodox and fit for an imprimatur in order that the church would not appear to be contradicting ‘science’ - the consequences of which Pope Urban VIII said ‘would put the Catholic faith in danger’ - the solemn pontifical decree of Pope Paul V remained safe from ‘official’ denial.
Copernicanism then was in effect demoted from formal heresy to material heresy by virtue of the derogation. Material heresy is where the person intends no contradiction to Church teaching in his or her belief. Under the impression science has proven H, the Copernican feels he or her has no choice but to reject the 1616 decree.
But the principle remains. The Church is perceived as having made an error while defining and declaring on a matter of faith. there are those of us who now - against huge odds - try to reassure Catholics that no such error exists. Alas, faith in science has now surpassed faith in faith. This forum and various threads prove this.
So, we must admit, in a way Catholics are not obliged to accept the decree as it stands derogated. However, should a future pope reverse this error, - which I doubt before the final judgement - it could once again become an obligation.