The Arthur Ross Terrace will be closed this morning, Tuesday, October 21, for a private cultural observance. You many observe smoke and/or fire coming from the Terrace at that time. The FDNY has been notified in advance, and all safety precautions are in place. The Terrace will reopen at 1 pm.
If the Hayden Sphere is the size of the Local Group of galaxies, then this model is the relative size of Messier 101.
Messier 101 is a spiral galaxy about 25 percent larger than our Milky Way Galaxy.