The astronauts Jim Newman and Mike Massiminowho started an extensive series of upgrades Monday on Hubble, installed a new camera on the telescope on Thursday. Called the Advanced Camera for Surveys, or ACS, the camera is expected to greatly improve Hubble's ability to create images of the cosmos. It was latched into place about 7 a.m. EST and a short while later NASA reported that it had passed its first tests and was checking out well. The last of five planned Hubble spacewalks is to be made early Friday morning. The astronauts Jim Newman and Mike Massiminowho started an extensive series of upgrades Monday on Hubble, installed a new camera on the telescope on Thursday. Called the Advanced Camera for Surveys, or ACS, the camera is expected to greatly improve Hubble's ability to create images of the cosmos. It was latched into place about 7 a.m. EST and a short while later NASA reported that it had passed its first tests and was checking out well. The last of five planned Hubble spacewalks is to be made early Friday morning.