text-only page produced automatically by LIFT Text Transcoder Skip all navigation and go to page contentSkip top navigation and go to directorate navigationSkip top navigation and go to page navigation
National Science Foundation Home National Science Foundation - Mathematical & Physical Sciences (MPS)
Astronomical Sciences (AST)
design element
AST Home
About AST
Funding Opportunities
Career Opportunities
AST Presentations
Astronomy & Astrophysics Advisory Committee (AAAC)
AST Portfolio Review
See Additional AST Resources
View AST Staff
MPS Organizations
Astronomical Sciences (AST)
Chemistry (CHE)
Materials Research (DMR)
Mathematical Sciences (DMS)
Physics (PHY)
Office of Multidisciplinary Activities (OMA)
Proposals and Awards
Proposal and Award Policies and Procedures Guide
Proposal Preparation and Submission
bullet Grant Proposal Guide
  bullet Grants.gov Application Guide
Award and Administration
bullet Award and Administration Guide
Award Conditions
Merit Review
NSF Outreach
Policy Office
Additional AST Resources
Career Opportunities
Other Site Features
Special Reports
Research Overviews
Multimedia Gallery
Classroom Resources
NSF-Wide Investments

Email this pagePrint this page

Press Release 08-021 - Video
Microlens Animation

This animation explains gravitational microlensing.
View Video

This animation explains gravitational microlensing.

Credit: Trent Schindler, National Science Foundation

Back to article

Video Transcript:

When a star shines light into space, the light rays will generally travel along perfectly straight lines. But not always. If some of the rays pass close to a massive object, like another star, they will be bent inward by the object's gravitational field. In effect, the field will concentrate the light like a cosmic magnifying glass. So astronomers call this phenomenon a gravitational lens. Astronomers call it a microlens when the effect is created by a very dim object that wanders in front of a distant star and focuses the light just enough to make the star seem a bit brighter. This makes microlensing a powerful tool for detecting objects that would otherwise be lost in the vastness of space. Sometimes astronomers can even tell if from the changes in brightness if the small, dim object has a smaller, dimmer companion -- a planet.

Related media icon
This video requires the free Windows Media Player plug-in


Email this pagePrint this page
Back to Top of page