2022-01-19, 04:39 PM
Hi BMD,
Aren't all of the programs that use the 6 parameters that describe the shape & orientation of the elliptical orbit using osculating elements to approximate the motion? The question is which elements are they using? When ST4v downloads the MPC's 'NEAs at Today's Epoch' elements, there are ~27,000 element sets in the file. As of today, ST4v is using the epoch 2022 Jan 19 0000 UTC as 'Today's Epoch' for the NEAs & the OI displays the epoch as 2022 Jan 18 because it's the evening of Jan 18.
Currently MPC's 'standard' epoch is 2022 Jan 21 0000 UTC & that's the epoch ST4v uses when it downloads MPCORB since mid-October 2021. At least that's the way it seems to work, Technoking can confirm this. If I understood what Greg was saying, ST4v will use the elements with the epoch from the MPC that are the farthest into the future, either 'Today's' or the 'Standard' & keep those & ignore the other.
Perhaps I've misunderstood something,
Phil S.
Aren't all of the programs that use the 6 parameters that describe the shape & orientation of the elliptical orbit using osculating elements to approximate the motion? The question is which elements are they using? When ST4v downloads the MPC's 'NEAs at Today's Epoch' elements, there are ~27,000 element sets in the file. As of today, ST4v is using the epoch 2022 Jan 19 0000 UTC as 'Today's Epoch' for the NEAs & the OI displays the epoch as 2022 Jan 18 because it's the evening of Jan 18.
Currently MPC's 'standard' epoch is 2022 Jan 21 0000 UTC & that's the epoch ST4v uses when it downloads MPCORB since mid-October 2021. At least that's the way it seems to work, Technoking can confirm this. If I understood what Greg was saying, ST4v will use the elements with the epoch from the MPC that are the farthest into the future, either 'Today's' or the 'Standard' & keep those & ignore the other.
Perhaps I've misunderstood something,
Phil S.