These are descriptions of a selected group of projects being observed this month.
Information is also available for past projects.
Variations in the four images show time delays due to path differences resulting from the gravitational potential of the lens and are dependent on the Hubble constant. This project will attempt to place narrow constraints on the gravitational potential. While the four images have been unresolved by the VLBA in prior observations, this increase in flux may enable the VLBA to resolve the images. The mapping of the position of this new jet component in the images of the background galaxy will provide an important constraint on the lens gravitational potential and hence a more accurate value for the Hubble constant . Back to top.