New answers tagged

2

It is the first one, i.e. as soon as the heavenly body can be first seen. Here a definition from http://www.ga.gov.au/scientific-topics/astronomical/astronomical-definitions Sunrise is defined as the instant in the morning under ideal meteorological conditions, with standard refraction of the Sun's rays, when the upper edge of the sun's disk is coincident ...


4

a) What is the definition of completeness? Completeness is the number of objects in a data set that are detected over the number that exist. In astronomy, completeness is often estimated for a particular apparent magnitude or flux density. As an example, for sources that are as bright as the Sun (-27 magnitude), we have a completeness of 1. That is, we’...


2

In the linked article by A. Bouchard and another by J. Daley, the words "in the journal Lunar and Planetary Science" link not to a journal article but to a poster in a K-12 education session at the 2017 Lunar and Planetary Science Conference. First author Kirby Runyon told Universe Today in 2017 that he would not submit this geophysical definition ...


Top 50 recent answers are included