Telescope Reviews: The 1st Lunar daguerrotype plate by John W. Draper

There seems to be some doubt there as to when exactly the first Lunar photograph (or daguerrotype plate) was actually taken.

It is well known that the first daguerrotype of the Moon was taken by John William Draper, the father of Henry Draper. There is some speculation that the first plate taken on the 18th of December in 1839 did not actually succeed, but that the first plate was rather taken on the 23. of March 1840. Also this text on page 65 argues, that the first photo was taken by Draper in 1840. Yet, along the actual pic there is the date 18th December 1839 there.

To settle this confusement, I used Jim Mosher's excellent Lunar Terminator Visualization Tool and loaded the ephemeris data (of the JPL) from 1800 onwards.

The program shows that on the 18th of December 1839 the angular diameter of the Moon (at 19.00 UT) was 2020.4 arc-seconds, colongitude 66.046 and 95.42 per cent of the Moon was illuminated (before the full Moon).

On the 23rd of March 1840 the angular diameter of the Moon (at 19.00 UT) was 1754.2, colongitude 153.848 and 72.46 per cent of the Moon was illuminated (after the full Moon).

In the montage, the uppermost (left) pic shows the first Lunar daguerrotype plate by John William Draper.

In all the LTVT -pics the terminator position is shown with the red line. In the montage, the second pic (downmost left) shows (with LTVT) the Moon on the 18th of December 1839 (at 19.00 UT). This is clearly the one. Just to be sure, the third pic (downmost right) shows the Moon (with LTVT) on the 23rd of March 1840.

Edited by Mare Nectaris (01/03/09 01:58 PM)