What do this data mean please?


enter image description here

  • 3
    $\begingroup$ You should explain what it is that you do understand about the paper first, and demonstrate that you've put some effort into understanding it. This looks like a tiny crop from a random page from a 42 page paper, written in French, possibly a century ago. $\endgroup$ – uhoh Sep 14 at 5:46

The Niesten 1904 double star catalog explains its tables on page 2:

Catalogue explanation in French

The entry in question is for δ Orionis.

"A = 2" means the primary component was estimated at apparent magnitude 2.

"1879,12" is an observation date in fractional years, using a comma as a decimal point.

"163,0" and "161,7" are position angles from the primary component to the secondary, in degrees counterclockwise from celestial north. The * indicates an observation by Stuyvaert instead of Niesten. "162,35" is an average of the two observations.

"en contact" means the separation between the two was smaller than the telescope's angular resolution. Otherwise their separation would be given in arcseconds.

  • $\begingroup$ Thank you very much $\endgroup$ – Arrara Sep 16 at 4:15

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.