2. Bessel Smart Van Der Kamp YTPC

3. HIP

4. YTPC HIP SIM

5. YTPC HIP SIM GAIA

6. SIM HIP/YTPC YTPC HIP SIM GAIA

7. NEARBY NEIGHBOURS GAIA/SIM WON’T SEE Ricky Smart, Beatrice Bucciarelli, Mario Lattanzi, Hugh Jones. OATo – U.Herts

8. Richard SmartIAU 248 2007-10-18 L + T Dwarfs Complex Mass-Luminosty-Metalicity-Age relation Same spectral type different luminosity or mass e.g. 0.05M start life as M, 0.1-1GYR L, finishes as a T Distances: luminosity, large numbers  LF assume a radius -> effective tempreature large velocities or low luminosity => sub-dwarfs over luminous => binary

9. Richard SmartIAU 248 2007-10-18 608 from www.dwarfarchives.org 5/10/2007www.dwarfarchives.org Known L+T Dwarfs

10. Richard SmartIAU 248 2007-10-18 DISTANCES + MAGNITUDES Literature z,i or spt+J -> z,i (Hawley et al 2002) Transform z,i to GAIA-G (internal OATo) Calculate a spectro-photometric distance SIM fainter but works bluer…

11. Richard SmartIAU 248 2007-10-18 All L+T dwarfs within 50pcs.

12. Richard SmartIAU 248 2007-10-18 Those seen by GAIA.