2017 Topps Allen & Ginter Constellations mini inserts
Ginter is known for off-kilter insert sets, occasionally going outside the box with something wonderfully weird, and in 2017 they included a 10-card set of constellation minis. These cards appear to be blank on the front at first glance, though if you take a closer look, you can see the faint constellation. When you get them in the dark, a constellation is illuminated. Kinda neat.
Here's a "night sky" of all 10 cards together. The glowing is fine, but could be brighter. I had to edit the levels on photo(s) a bit to make the glowing stand out more.
Here's a closer look at the 10 cards.
#1 Orion & #2 Ursa Major:
#3 Ursa Minor & #4 Scorpius:
#5 Cygnus & #6 Leo:
#7 Perseus & #8 Hercules:
And finally, #9 Aquarius & #10 Libra:
I've always enjoyed stargazing, though I never really studied up much on different stars and constellations. I took a beginner astronomy class as an elective back in junior college, and seem to recall earning an A, but haven't retained any of that knowledge, unfortunately. But hey, these cards make for a nice primer for anyone interested in that stuff, so kudos to Topps for working constellations into Allen & Ginter in a unique way.