Full Idea
Hempel said every scientific explanation is potentially a prediction - it would have predicted the phenomenon in question, had it not already been known. But also the information used to make a prediction is potentially an explanation.
Gist of Idea
Explanatory facts also predict, and predictive facts also explain
Source
report of Carl Hempel (Aspects of Scientific Explanation [1965]) by Samir Okasha - Philosophy of Science: Very Short Intro (2nd ed) 3
Book Reference
Okasha,Samir: 'Philosophy of Science: very short intro (2nd ed)' [OUP 2016], p.40
A Reaction
Sounds too neatly glib to be quite true. If you explain a single event there is nothing to predict. You might predict accurately from a repetitive pattern, with no understanding at all of the pattern.