Speaker:
Dr. Leslie J. Deutsch

Session 1

Date and Time: 9:00 – 10:00 AM, Jan 31st

Abstract:
Communications with NASA’s spacecraft visiting other planets is a difficult problem.
For example, it is 100 times harder to communicate with a spacecraft at our Moon
than with one in geosynchronous Earth orbit – and approximately four hundred
million times harder from a spacecraft at Jupiter. NASA’s deep space communication
systems are among the most efficient anywhere. The antennas of the Deep Space
Network (DSN) can detect signals so weak that they would have to be integrated for
ten trillion years to power a refrigerator light bulb for one second. These efficiencies
are the product of decades of research into antennas, detectors, modulations, and
coding. We will consider two real-word examples of how NASA engineers and
mathematicians solve difficult communications problems in this context: the failure
of the high gain antenna on NASA’s Galileo mission to Jupiter, and the anomalous
relay radio design that almost led to a failure of the Cassini Huygens probe of
Saturn’s moon Titan. Both of these problems had to be solved on Earth while the
respective spacecraft were already well on their way to their destinations. We will
then consider some challenges for the future where further research will enable
new kinds of space missions.