You Can Request Observing Time On the Hubble Telescope

Unlike on many previous NASA space science missions, anyone can apply for observing time on the Hubble Space Telescope. The process of observing with Hubble begins with the annual Call for Proposals issued by the Space Telescope Science Institute to the astronomical community. Astronomers worldwide are given approximately two months to submit a Phase I proposal that makes a scientific case for using the telescope. It takes 96 minutes for the telescope to make one trip around the Earth, but because the Earth usually blocks the target for part of the orbit, typical observing time is only about 55 minutes per orbit. Proposals are further identified as general observer (GO), which range in size from a single orbit to several hundred, or snapshot, which requires only 45 minutes or less of telescope time. After observing time is awarded, the Institute creates a long-range plan. The journey from proposal through selection and scheduling takes at least a year, sometimes longer.