Foundation Award for Research

Michael Reed

Dr. Michael Reed

College of Natural and Applied Sciences
Physics, Astronomy and Materials Science

I. Focus of Research

My research can be classified as observational astronomy. I am largely concerned with obtaining and/or interpreting astronomical data, mostly imaging. The science I do is concentrated into two specializations: seismology of vibrating, evolved, compact stars and extrasolar planets.

My seismology work is the more established of the two areas. In order to understand what is occurring within stars, we have to be able to probe their insides. However, starlight leaves their exteriors, and so getting to their interiors requires alternate methods. One such method is to use their vibrations as probes. The insides of stars are fairly turbulent environments and often that turbulence can drive the star to rhythmically vibrate. How long it takes those vibrations to occur provide information about what is occurring inside. The challenge then becomes twofold: interpret the vibrations and generate models which describe the interior conditions and match the vibrations. By and large my work is to interpret the vibrations themselves into what we term as 'modes' which are subsequently compared to models. The stars I work on are about four times hotter than our Sun, but 20% the size and about twice as old. As such, they represent conditions our Sun will have in the distant future. Over the last four years, NASA's Kepler Spacecraft, which does not orbit the Earth, but orbits the Sun directly, has been observing one region of space, taking images every minute. The vibrations in stars produce small brightness changes in the stars, which the Kepler Spacecraft measured, over, and over, and over again. The timescale of the vibrations I study are a couple of hours, down to a few minutes, so over the course of four years, Kepler has observed tens of thousands of them. It has provided us accurate measurements to a few parts in a million, which is about a factor of 100 better than anything we can get from Earth, and virtually without interruption over the four year period.

More recently, I have begun working on planets around other stars- extrasolar planets, or exoplanets for short. Several thousand planets have now been detected, but a particular class caught my attention. These are rocky planets which orbit their Suns in less than a few days. As such, the surfaces of these planets are extremely hot, possibly even molten. However, the planets themselves could not have formed so close to their stars, and so must have formed further out, possibly even at distances where they would have been Earth-like. Over some quantity of time, they moved inwards. Those planets would likely have formed with roughly the same constituent chemistry as the Earth, or Mars, or Venus, and that original chemistry would determine what atmospheres they would have when heated. So along with a theorist at Washington University, and lab scientists at NASA's Glenn Research Center, and our own Dr. David Cornelison, we initiated a project to attempt to determine what atmospheres these exoplanets have. The project is now just entering its second year and all collaborators are hard at work to generate each portion of the puzzle.

II. Major Projects

“RUI: Asteroseismology of subdwarf B stars as representatitives of high-temperature physics and horizontal branch stellar cores” funded by the National Science Foundation. 2013-2016

“Understanding the Atmospheres of Hot Earths and the Impact on Solar System Formation” funded by NASA 2013-2016

“RUI: Asteroseismology of pulsating Subdwarf B stars via observational mode identification and modeling.” funded by the National Science Foundation. 2010-2013

“RUI: The Baker Observatory Sub-minute Survey: Exploring the galaxy at high temporal resolution.” funded by the National Science Foundation. 2009-2011

III. Future Directions of Research

My research will continue to mostly use space-based observations and large surveys which cover long durations of time. These sorts of data have proven to be most useful for understanding the vibrations within stars. In addition, I intend to continue pursuing exoplanet studies. This is such an exciting new realm of astronomy that it's too good to pass up. My goal is to determine how many solar systems like ours are out there and how many Earth-like planets may exist (termed eta Earth). Currently, it looks like the fraction of Earth-like planets where water could exist is enormous- so enormous that alien life should be a near certainty. The only issue then would be, where is it? Our planet is 1/3 the age of the Universe, so there is no reason to believe we should be the first. These questions are really fundamental to understanding the human experience and our place within the Universe. What could be more interesting than that?

IV. Topics related to your research and of interest to the broad University Community, for which you are available for presentations and/or consultations.

Stars- virtually anything about them. Their sizes, distances, evolution.

Exoplanets- planets around other stars. This field is growing so quickly that I would not claim complete expertise on the topic, but I am marginally well-versed in the latest developments.