Marylanders can look upward this weekend and spot the International Space Station flying past a blue moon.
The space station will pass over the Baltimore region both Friday and Saturday nights.
On Friday, look for it to appear over the southwest horizon at about 10:17 p.m., passing through the Big Dipper about 10:21 p.m., and setting in the northwest by 10:25 p.m.
Saturday night, it will follow a similar path from 9:27 to 9:34, passing by the bright star Vega just before disappearing.
That is also the night of the full flower moon, which also happens to fit the traditional definition of a blue moon.
The moon becomes full at 5:11 p.m., about three hours before it will rise large and bright in the east.
It will still be low in the southwestern sky when the space station zips across the middle of the sky a little over an hour after that.
Traditionally, a blue moon is the third full moon in a season with four full moons (though the term has come to also be applied to the second full moon in a single calendar month).
Saturday’s full moon is indeed the third one since the vernal equinox occurred March 20 — the full worm moon came just hours after the equinox marked the official start of spring, and the full pink moon came April 19.