Embargoed until 2:00 pm (EST), November 3, 1999

Gravitational Microlensing Evidence for a Planet Orbiting a Binary Star System

The Microlensing Planet Search Collaboration and 
the Wise Observatory - GMAN Team

The Microlensing Planet Search (MPS) Collaboration aims to detect planets that orbit distant stars by detecting the influence of the planets on gravitational microlensing event light curves. Gravitational microlensing events are observed via the time-varying magnification of the sum of all the gravitationally lensed images as the lens system passes in front of a background source star.
Observations and light curve modeling of gravitational microlensing event MACHO-97-BLG-41 indicate that the lens system consists of a Jovian planet orbiting a binary star system.
If our interpretation of this light curve is correct, it represents the first discovery of a planet orbiting a binary star system and the first detection of a Jovian planet via the gravitational microlensing technique.

The best fit light curve of the MACHO-97-BLG-41 microlensing event.
The data consists of 356 MPS R-band observations from the Mt. Stromlo 1.9m telescope, 197 MACHO-R and 194 MACHO-V band observations from the Mt. Stromlo 1.3m telescope, 35 R-band observations from the CTIO 0.9m telescope, and 17 R-band observations from the Wise 1.0m telescope. The MACHO-R, MACHO-V, Wise-R, CTIO-R, and MPS data are plotted in red, blue, green, cyan, and magenta respectively.
The tick interval for the inset figures is 1 day. 


Simulates a 3D view of the triple system, illustrates the microlensing concept, and shows the lensing event as it would have appeared at micro-arcsecond resolution -- and in reality.

2 MB
Low resolution , small frame

0.5 MB
Low resolution , small frame,
1st half: binary stars & planet

0.5 MB
Low resolution , small frame,
2nd half: lens animation

17 MB gzipped
(98 MB uncompressed)
Full resolution,large frame
README Explanation of the video
In Unix, you can view the animation with xanim.

Credits for Animations:
Created by  Orit Bergman and Guy Friedman
Zapa Digital Arts, Tel-Aviv, Israel 
Directed by Dr. Dan Maoz,
Wise Observatory , Tel-Aviv University, Israel
Based on calculations by Dr. David Bennett and Dr. Sun Hong Rhie
Department of Physics,University of Notre Dame