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Updated: May 4, 2026
10:01
Demonstration of a Hyperlens-integrated Microscope and Super-resolution Imaging
Published on: September 8, 2017
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One or more bound planets per Milky Way star from microlensing observations
A Cassan1, D Kubas, J-P Beaulieu
1Probing Lensing Anomalies Network (PLANET) Collaboration, Institut d'Astrophysique de Paris, Université Pierre & Marie Curie, UMR7095 UPMC-CNRS, 98 bis boulevard Arago, 75014 Paris, France. cassan@iap.fr
Nature
|January 13, 2012
Summary
Planets are common around stars, with most stars hosting planets. Gravitational microlensing reveals that Jupiter-mass planets orbit 17% of stars, while cool Neptunes and super-Earths are even more abundant.
Area of Science:
- Astronomy and Astrophysics
- Exoplanetary Science
Background:
- Most known exoplanets are detected via radial velocity or transit methods, biased towards planets close to their stars.
- Current estimates suggest 17-30% of solar-like stars host a planet.
- Gravitational microlensing offers a complementary method to detect planets farther from their stars or unbound ones.
Purpose of the Study:
- To statistically analyze gravitational microlensing data from 2002-2007.
- To determine the abundance of bound planets within 0.5-10 AU of their host stars.
Main Methods:
- Statistical analysis of gravitational microlensing data.
- Detection of exoplanets using the gravitational microlensing technique.
Main Results:
- 17% of stars host Jupiter-mass planets (0.3-10 M(J)).
- 52% of stars host cool Neptunes (10-30 M(⊕)).
- 62% of stars host super-Earths (5-10 M(⊕)).
Conclusions:
- Planetary systems are a common occurrence around stars.
- The prevalence of planets suggests planet formation is a general process.
- Gravitational microlensing significantly expands our understanding of planet populations.
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