The data had hardly started coming through the pipeline when astronomers made the first Frontier Field discovery: a supernova in the galaxy cluster MACSJ0717, one of the first of the Frontier Fields to be imaged.
The Frontier Fields designation for this object is SN HFF13Zar, and its nickame is “SN Zara.”
Supernovae discovery is an offshoot of Frontier Fields science because Hubble will be revisiting many of these fields several times over the next three years, allowing astronomers to compare recent images with older ones, and look for things that are different.
The supernova is located 1.73 arcmin from the center of the MACSJ0171 cluster and is a whopping 23.53 (+- 0.05) magnitude.
I say whopping, but big numbers on the magnitude scale mean an object is very, very dim. This is definitely a faint supernova, but not out of the ordinary in terms of what Hubble can see. Hubble can see things as faint as 31st magnitude, which is slightly fainter than objects that can be viewed by the best ground-based telescopes.
Without getting too crazy into the magnitude scale topic, suffice it to say for our purposes that
One magnitude thus corresponds to a brightness difference of exactly ...