Gravitational microlensing of MACHOs in the Large Magellanic Cloud
Microlente gravitacional de objetos MACHO en la Gran Nube de Magallanes
- Date
- 1993 · confidence high
- Place
- Mount Stromlo Observatory, Canberra, Australia
- Credited to
- MACHO Collaboration (Charles Alcock and colleagues)
- Field
- Cosmos & Earth
⚠️ Disputed: the sources disagree.
What was discovered
The MACHO project, with a telescope at Mount Stromlo, detected the temporary brightening of stars in the Large Magellanic Cloud caused by a compact object passing in front. It searched for dark matter in the galactic halo and established microlensing as a technique for stellar populations.
The EROS (France) and OGLE (Poland) teams published near-simultaneous detections in 1993; MACHO's is the first of the series. The final result showed that compact objects cannot account for the halo's dark matter.
What it led to
- searches for exoplanets by microlensing (OGLE, MOA)
- limits on the fraction of dark matter in compact objects
- maps of Milky Way structure using microlensing