Pathway to the Galactic distribution of planets: combined Spitzer and ground-based microlens parallax measurements of 21 single-lens events

S. Calchi Novati, A. Gould, A. Udalski, J. W. Menzies, I. A. Bond, Y. Shvartzvald, R. A. Street, M. Hundertmark, C. A. Beichman, J. C. Yee, S. Carey, R. Poleski, J. Skowron, S. Kozłowski, P. Mróz, P. Pietrukowicz, G. Pietrzyński, M. K. Szymański, I. Soszyński, K. UlaczykŁ. Wyrzykowski, M. Albrow, J. P. Beaulieu, J. A. R. Caldwell, A. Cassan, C. Coutures, C. Danielski, D. Dominis Prester, J. Donatowicz, K. Lončarić, A. McDougall, J. C. Morales, C. Ranc, W. Zhu, F. Abe, R. K. Barry, D. P. Bennett, A. Bhattacharya, D. Fukunaga, K. Inayama, N. Koshimoto, S. Namba, T. Sumi, D. Suzuki, P. J. Tristram, Y. Wakiyama, A. Yonehara, D. Maoz, S. Kaspi, M. Friedmann, E. Bachelet, R. Figuera Jaimes, D. M. Bramich, Y. Tsapras, K. Horne, C. Snodgrass, J. Wambsganss, I. A. Steele, N. Kains, V. Bozza, M. Dominik, U. G. Jørgensen, K. A. Alsubai, S. Ciceri, G. D’Ago, T. Haugbølle, F. V. Hessman, T. C. Hinse, D. Juncher, H. Korhonen, L. Mancini, A. Popovas, M. Rabus, S. Rahvar, G. Scarpetta, R. W. Schmidt, J. Skottfelt, J. Southworth, David Starkey, J. Surdej, O. Wertz, M. Zarucki, B. S. Gaudi, R. W. Pogge, D. L. DePoy

Research output: Contribution to journalArticlepeer-review

56 Citations (Scopus)
4 Downloads (Pure)


We present microlens parallax measurements for 21 (apparently) isolated lenses observed toward the Galactic bulge that were imaged simultaneously from Earth and Spitzer, which was ~1 AU west of Earth in projection. We combine these measurements with a kinematic model of the Galaxy to derive distance estimates for each lens, with error bars that are small compared to the Sun's galactocentric distance. The ensemble therefore yields a well-defined cumulative distribution of lens distances. In principle, it is possible to compare this distribution against a set of planets detected in the same experiment in order to measure the Galactic distribution of planets. Since these Spitzer observations yielded only one planet, this is not yet possible in practice. However, it will become possible as larger samples are accumulated.
Original languageEnglish
JournalAstrophysical Journal
Issue number1
Early online date24 Apr 2015
Publication statusPublished - 1 May 2015


  • Gravitational lensing: micro
  • Planetary systems
  • Planets and satellites: dynamical evolution and stability


Dive into the research topics of 'Pathway to the Galactic distribution of planets: combined Spitzer and ground-based microlens parallax measurements of 21 single-lens events'. Together they form a unique fingerprint.

Cite this