The supernova Ia 2011fe in M101, its tip of the red-giant branch (TRGB)
  distance, and the value of H_0
  The light curve parameters of the normal type Ia SN2011fe are derived from
the rich archive of the AAVSO. This leads, together with the TRGB distance
modulus of (m-M) = 29.39 +/- 0.05 of the parent galaxy M101, to maximum
magnitudes of the unreddened SN of M_B = -19.45 +/- 0.08, M_V = -19.46 +/-
0.08, and M_I = -19.25 +/- 0.06 (for the standard decline rate of Delta m_15 =
1.1). When these values are inserted into the Hubble line defined by 62 SNe Ia
with 3000 < v < 20,000 km/s - and considering also four other SNe Ia with TRGB
distances - one obtains a large-scale value of the Hubble constant of H_0 =
64.3 +/- 1.9 +/- 3.2. This value can be much improved in the future by using
only TRGB distances of SNe Ia.
