Like with some other days and months we call 'celebrations', it's more of a marking than a celebration imo. People don't take to the streets en masse to chant "stop killing us!" or somberly paint the names of the dead on walls, during genuine celebrations. On the Months and days where a lot of this occurs, I think we're supposed to be reflecting on more than Marie Curie's career or the fact that someone gave birth to us.