What could have happened to these eggs??

[Miss Cheep]

Hello, I have a broody muscovy duck and her eggs were due to hatch tomorrow. All of her eggs look like the picture attached below. She is a first time mother and is only sitting on six eggs. What happened to them and why to all of them? Is there any possible chance that they could hatch? Thanks!

 

[sourland]

Given the time of year, I would guess that the eggs got excessively chilled/frozen prior to incubation and were not viable.