Data from several HST proposals were used for this science. These include: 9352, 9728, 10189, 10339, and 10802, PI: A. Riess (STScI/JHU). Data specific to observations of NGC 3021 are from HST proposals 10802 and 10497 PI: A. Riess (STScI/JHU).
The science team includes: A. Riess (STScI/JHU), L. Macri (Texas A&M University), S. Casertano and M. Sosey (STScI), H. Lampeitl (STScI/University of Portsmouth, UK), H. Ferguson (STScI), A. Filippenko (University of California, Berkeley), S. Jha (Rutgers University), W. Li and R. Chornock (University of California, Berkeley), and D. Sarkar (University of California, Irvine).
ACS: F555W (V) and F814W (I)
NICMOS: F160W (H-band)