Salle Michel Hénon (a.k.a. salle du conseil), Institut d'Astrophysique de Paris, France.
There is a partnership agreement with Hotel du Lion which is just next to IAP. To give an example: instead of 120 euros / night we can get 96 euros / night (+ 8 euros / night for breakfast + 0.99 euros / night Paris fee) for a room with a large bed . The website is the following: http://paris-hotel-lion.com/
To see the rates go in "Corporate access" (just below the logo on the left), and enter "astrlion" (ASTRLION in minuscule) in the Corporate code. The other possibility is to write directly to them:
firstname.lastname@example.org, +33 1 40 47 04 00
The full indicative schedule of the meeting is available in the following PDF: BLSS_2017.pdf.