What does it mean when astronomers say planets are aligned?

1 Answer
Jun 5, 2017

It means that the planets are lined up in roughly a straight line coming out from the sun.


The planets orbit at different rates around the sun, like the hands of a clock. Sometimes the planets are at the same part of their arc around the sun at the same time. This is what it means to be aligned. If a line was drawn at this time from the sun the line would pass through all the planets that were aligned.