Creating a legacy and learning about dark energy. Commentary on: Astier P., Guy J., Regnault N., et al., 2006, A&A, 447, 31 Leibundgut, B. Abstract Publication: Astronomy and Astrophysics Pub Date: June 2009 DOI: 10.1051/0004-6361/200912209 Bibcode: 2009A&A...500..615L