an opening earthstar?

Description:

Spotted on 6/20/10. Thin white wrinkled outer covering was crackling open. Inside was an olive green/grey softish round fungal ball. Is this an earthstar about to open up? Didn't open before I left and it was Sunday on Governors Island and I wouldn't be able to check it again for a while. It was also Punk Island that day so I put an orange cone by it so it wouldn't get moshed on.

Habitat:

grassy lawn at Picnic Point, Governors Island, NY

Notes:

didn't open before I left unfortunately