I would like to introduce 3 stories: 1) Hyper-Suprime Cam (HSC) SN Survey, 2) Blackbody Stars & 3) Close Binary System. With the LPNHE team, we are conducting a high-redshift supernova survey with the Subaru Hyper-Suprime Cam (HSC). HSC is the fastest camera today before LSST turns on. Hubble Space Telescope is giving us accurate Infrared measurements, and the large telescopes around the world, Gemini, Keck, AAT, and GTC are executing spectroscopic follow-ups. LPNHE plays a major role in getting spectra with VLT and DESI. I report the status of our journey to the most accurate measurement of the dark energy. One of the major systematic errors originates from the fundamental photometric calibration, and I'm proposing to make use of perfect blackbody stars which were discovered serendipitously from SDSS, and we are finding 35 blackbody stars out of 1.8 billion GAIA stars (one in 50 million) and I will discuss the identity of these stars.As of today, we are still debating the progenitor system of the Type Ia supernova (SNIa). We are seeking the potential SNIa progenitor system in the Milky Way galaxy and identified some candidates. An overdue supernova in our Galaxy may be a Type Ia supernova. I conclude with the near future opportunities with Euclid, JWST, and LSST.
