Many independent dating methods agree, and a young earth requires all of them to be wrong at once
The objection
This is the strongest objection on the page and it should be felt at full weight. The methods that give an old earth do not depend on each other. Radiometric dating rests on nuclear physics, and isochron methods are built specifically to detect the contamination and initial-daughter problems that critics raise. Greenland and Antarctic ice cores are counted like tree rings — visible annual layers, cross-checked against volcanic ash horizons of independently known date. Varves are annual sediment couplets in lake beds; the sequence in Lake Suigetsu in Japan runs tens of thousands of layers deep and cross-calibrates radiocarbon. Corals band annually. Dendrochronology chains overlapping tree rings back many thousands of years continuously. Astronomy is the plainest of all: light from objects far outside our galaxy has been travelling for far more time than a young earth allows, and the physics of that transit is the same physics that makes GPS work. These come from separate disciplines, with separate assumptions, done by people with no coordination and often no interest in the question. For the earth to be young, every one of them must fail — and fail in the same direction, by roughly the same factor. Coincidences of that scale do not happen.
The response
This is the objection a young-earth reader most needs to sit with, and it will not be waved off here. The convergence is real, it is the reason the overwhelming majority of working scientists hold deep time, and any believer who imagines the case is thin has not looked at it. Three things can honestly be said. First, the convergence is not as fully independent as it appears at every point — calibration curves are cross-tied, and radiocarbon in particular is calibrated against the tree-ring and varve sequences rather than confirming them from scratch — but this qualification applies to some links and not to the whole chain, and it does nothing to the astronomical argument. Second, young-earth proposals exist for the starlight problem: Humphreys offered a relativistic cosmology in which time runs differently in different frames, and Jason Lisle has argued that the one-way speed of light is a convention rather than a measurement. These are proposals, not results, and this page will not present them as though the field had accepted them. Third, and most honestly: MannaFest holds this position because of what it believes the text says, and it does not claim the scientific case is currently in its favor. That is the actual shape of the disagreement, and calling it something else would be a lie. What a young-earth reader owes the objection is not a clever answer but the admission that this is where the weight sits — and what the objector owes in return is the recognition that the argument from the text is an argument, not an evasion.