Security problems running Java apps? In its Update 51 Java 7 raised the security restrictions and does not accept university "self-issued" security certificates. We are working at resolving this problem, but a temporary fix is to add the site to the Java Exception site list in your Java.
To do so bring up the Java Control Panel (found under System Preferences in a Mac, or here in Windows, or by typing 'java -viewer' in Linux and closing the 'Java Cache Viewer' window). Click on the 'Security' tab. Using the 'Edit Site List...' button add '' to the list of sites. The system will complain that it is not a 'secure' https connection, but confirm it anyway. That should fix any problems with security exceptions.

Why is the sky dark at night? Olbers’ Paradox

Light at different wavelengths. Explore the appearance of galaxies

Understanding astronomical redshifts. Velocity and the Doppler effect

Understanding cosmological redshifts. Doppler effect from changes in path

Light responds to gravity. A gravitational lensing explorer

The expansion of the universe. Play with Hubble’s law

The fate of the universe. Play with the cosmological parameters and see their effects

Gravity, orbits, and Black Holes. How do astronomers measure mass?

Developed by Joseph Benik, Sam Knutson, Justin Zelinsky, Paige Junghans, and Rohan Pathare
Supervised by Melissa Hayes-Gehrke and Alberto Bolatto

Sponsored by the National Science Foundation  
and the Research Corporation for Science Advancement