Astronomy Career Paths

The American Astronomical Society (AAS) and the American Institute of Physics (AIP) recently sent out the first survey of a planned 10 year “longitudinal study” that will follow astronomy and astrophysics graduate students registered in 2006-2007 throughout their early careers. The idea is to better understand not only the wide variety of career outcomes, but also the motivations underlying the decisions that lead to each path. This will hopefully allow the study to identify any factors in the culture of astronomy that might discourage some sectors of the initial student population from pursuing long-term careers in the field. Although certainly not as scientific as a formal survey, individual graduate programs could get a sort of “sneak preview” of this longitudinal study by finding everyone from their incoming class of 1996-1997 and asking what they are doing now. I performed an informal survey for one such class, which began with eleven incoming students in a large astronomy graduate program at a major public university. The sample consisted of seven males and four females, including seven domestic and four international students (one of them female).

At the end of the first year of graduate study, one female domestic student was asked to leave the program for academic reasons, and one male international student left the program to pursue a graduate degree in computer science at another university. The current status of these two students is not known, although the absence of recent scientific publications suggests that neither of them are presently doing astronomy research. After finishing coursework in the second year, four students ultimately decided to leave the program with a Master's degree, including three males (one of them international) and one female. The male international student transferred into the computer science graduate program at the same university and went on to work as a software developer for a local company. One male domestic student immediately obtained a software engineering and management job at a local startup, and eventually took a similar position out of state, closer to his family. Another male domestic student began teaching astronomy at a nearby community college, where he continued working on the tenure track for 6 years while also earning a Master's degree in a related science. He was recently given tenure and became chair of the department. The female domestic student stayed in the program for 2 more years before becoming a high school teacher. She took some graduate courses in mathematics prior to leaving, allowing her to obtain certification in math and physics through an alternative program that ran concurrently with her first year of teaching. She taught math in nearby public high schools for 4 years, and is now teaching physics at a private high school where she eventually expects to teach an astronomy course as well.

Only five of the eleven incoming students ultimately earned a Ph.D. through the program: three males and two females with one international student of each gender. One male domestic student took a series of postdoctoral fellowships over nearly 5 years before obtaining a tenure-track research position at a national laboratory. The female international student was awarded prestigious back-to-back postdoctoral fellowships, providing a total of 7 years of support, and is currently beginning her sixth year as a postdoc. The female domestic student worked as an associate editor for a popular astronomy magazine and in an instructional support position for an undergraduate program at a private university before recently accepting a non-tenure-track position at a small teaching college. Another male domestic student worked for several years through a postdoctoral fellowship at an international observatory before being hired as a tenure-track instrument scientist with both research and support responsibilities. The male international student worked in a postdoctoral position at a public university for almost 3 years before becoming a faculty member at a university in his home country, with a continuing adjunct appointment at his postdoctoral institution.

This “anecdotal” longitudinal study suggests that it might be difficult to define a “standard career path” in astronomy, if such a thing even exists. The wide variety of outcomes for this one small sample of students certainly did not reveal any systemic problems in the culture of the field, since both male and female as well as domestic and international students were proportionally represented along each major career path. More than a decade after entering a graduate program in astronomy, the experience appears to have led most of these students to interesting and fulfilling careers that they each shaped through their personal choices. Future students can take comfort in knowing that graduate study in astronomy only seems to multiply their possible career options.

Extreme Exoplanet

About 5 billion years from now, the Sun will begin to exhaust its primary source of energy -- the hydrogen near the center that fuels nuclear fusion. The remnant helium core will begin to contract, and the surrounding shell of hydrogen will start to burn hotter. Our star will slowly bloat to 100 times its former size, becoming a "red giant" and possibly destroying some of the inner planets of our solar system. An unsettled question among astronomers is: could the Earth make it through such a catastrophic event?

New evidence in this longstanding debate surfaced this week, when an Italian-led group of scientists announced the discovery of the first planet around a distant star that appears to have survived this phase of stellar evolution. "The future of the Earth is to die with the Sun boiling up the oceans, but the hot rock will survive", said Don Kurtz, one of the coauthors of the investigation. The study focused on a star called V391 Pegasi, which is estimated to be about 10 billion years old and appears to have already gone through the red giant phase. This particular star is special: the light coming from its surface exhibits very regular pulsations, a kind of continuous "star-quake" that provides a window into its interior structure. The astronomers have been monitoring these pulsations for more than 6 years, and they noticed something interesting.

As expected, the period of the pulsations are increasing slightly over time -- a consequence of the continuing evolution of the star, which slowly modifies the interior conditions that determine the regularity of the pulsations. But in addition to the expected changes, the pulsations sometimes arrived a few seconds sooner or a few seconds later than predicted, in a pattern that suggests the star is wobbling around in space from the gravitational pull of an orbiting planet. This is the same technique that led to the discovery of the very first planets detected outside of our solar system in 1992, which were orbiting a distant pulsar. As it turns out, the planet around V391 Pegasi is close enough to the star right now that its orbit was probably the same size as the Earth's orbit around the Sun at the time the star became a red giant. The fact that the planet is still there suggests that close planets can, at least in some circumstances, survive this phase of stellar evolution.

Of course, more research is needed to determine whether or not V391 Pegasi represents a typical outcome for close planets. But, as Kurtz succinctly stated, "It is psychologically interesting to think that the Earth will survive." Even if all that's left is a hot rock.