No. 26: Mar-Apr 1983
The distances between terrestrial radio telescopes can be measured with incredible accuracy by pointing the telescopes at the same celestial targets and operating them as interferometers. The distances between telescopes a continent apart can then be pegged to within 5 centimeters. For example, the distance between radio telescopes at Fort Davis, TX, and Onsala, Sweden, is 7,940,732.17 ± 0.10 meters. If North America and Europe are drifting apart several centimeters per year, this change should have been noticed since 1979, when adequate geodetic precision became available. Actually, no drift has been noted.
(Thomsen, D.E.; "Mark III Interferometer Measures Earth, Sky, and Gravity's Lens," Science News, 123:20, 1983.)
Comment. Of course, continental drift could be episodic, with the continents now static.
Reference. Objections to continental drift are legion. Refer to ETL6 and ETL7 in our Catalog: Carolina Bays, Mima Mounds. Details here.