Introducing Christy Caudill

Christy  (@christycraters) is a planetary geologist currently working on her PhD at Western University, Canada, focusing on impact cratering products and processes. With former experience in Mars spacecraft operations as a HiRISE Downlink Specialist, and a former geologist at the Arizona Geological Survey, Christy has a background in terrestrial as well as planetary geology. Her current field site is the Ries Impact Structure (Germany), where she studies the mineralogy and other aspects of the ejecta deposits. Impact craters provide a window into the subsurface of planetary bodies, with the largest structures exhuming tens of kilometers of any available rock, water, and ice. The ejecta deposits are the result of that exhumation, which redistributes this material across the surface and forms new materials under intense heat and pressure. The deposits at the Ries Impact Structure are of particular interest to her research as they represent analogies to similar impact-generated deposits on Mars. Earth-Mars comparative studies allow researchers like Christy an avenue to extrapolate past Mars climate and habitability, soil production, and subsurface volatile availability.

Introducing Sarah Milkovich

Sarah Milkovich is a planetary geologist and system engineer at NASA’s Jet Propulsion Laboratory. Sarah works on spacecraft science operations, at the point where science and engineering meet. Sarah is currently the lead Science System Engineer for the Mars 2020 Rover, which will seek signs of ancient life on Mars. She has previously worked on Mars Science Laboratory (the Curiosity rover), the Mars Phoenix lander, the Cassini-Huygens spacecraft at Saturn, and Mars Reconnaissance Orbiter, where she was the investigation scientist for the HiRISE camera. She has won JPL and NASA team awards for her efforts to return the best possible science within spacecraft engineering constraints.

Sarah grew up in Ithaca, New York. She earned her B.S. in planetary science from Caltech, and her M.S. and Ph.D. from Brown University in planetary geology with studies of mountain glaciers and polar deposits on Mars, and volcanism on Mercury. Sarah currently lives in Los Angeles with her husband, Jason, their son Marko (4), and their Labrador retriever Ginger. She dabbles in knitting, beading, and playing trombone.  Sarah regularly tweets at @milkysa and very occasionally blogs at

Introducing Tyler Nordgren

Tyler Nordgren is a Professor of Physics and Astronomy at the University of Redlands. Prior to arriving at Redlands in 2001 he was an astronomer at both Lowell Observatory and the U.S. Naval Observatory in Flagstaff, Arizona. He earned his PhD in astronomy from Cornell University in 1997 for work on dark matter in interacting spiral galaxies. In addition to publishing roughly two dozen peer reviewed scientific articles he is also the author of “Stars Above, Earth Below: A guide to astronomy in the national parks,” a popular science book dedicated to revealing what visitors to America’s national parks can observe in a dark night sky. Since 2007, Dr. Nordgren has worked closely with the U.S. National Park Service Night Sky Program to promote astronomy outreach and night-sky preservation in national parks. Dr. Nordgren has helped document this vanishing landscape with award-winning artwork and night sky photography that has been on display in galleries from New York City to Flagstaff, Arizona and has been used in a number of national parks. He is a past-member of the Board of Directors for the International Dark-Sky Association. In 2012, NASA’s Curiosity rover joined Spirit and Opportunity on Mars carrying sundials, or “Marsdials” which Dr. Nordgren helped design with a team of seven other scientists and artists. His new book on the Great American solar eclipse of 2017 is coming out next year.

Introducing Tanya Harrison

Tanya Harrison is a Ph.D. candidate in Geology at the University of Western Ontario’s Centre for Planetary Science and Exploration (CPSX) in Canada. Her current research focuses on martian gullies—how they formed and evolved, and what they can tell us about climate change in Mars’ recent past. From 2008–2012, she was on the science operations team for the Context Camera (CTX) and Mars Color Imager (MARCI) aboard NASA’s Mars Reconnaissance Orbiter at Malin Space Science Systems in San Diego. She was also a science team collaborator for the Curiosity rover’s Mast Cameras (Mastcam), Mars Hand Lens Imager (MAHLI), and Mars Descent Imager (MARDI), working in science operations for all three cameras at Malin Space Science Systems.
Tanya holds a B.Sc. in Astronomy and Physics from the University of Washington, and a Master’s in Earth and Environmental Sciences from Wesleyan University. In addition to being a Ph.D. student, she is a Web Editor Intern with The Planetary Society, editor of the Geological Association of Canada’s “Planetary Matters” newsletter and keeper of their Twitter account (@pgg_canadian), and a professional photographer. She has also been very active in education and public outreach for over 15 years with organizations/events such as CPSX, Expanding Your Horizons, Norwescon, The Mars Society, and The National Space Society.
The rest of the 51 weeks of the year,  you can find Tanya tweeting at @tanyaofmars

Introducing Fred Calef III

This week we have Fred Calef III hosting astrotweeps. Fred graduated from the University of Alaska Fairbanks (UAF) in Geological Sciences in 2010. His dissertation was on fresh small rayed impact craters on Mars, looking at ejecta retention rates and what they tell us about the current environment and geomorphic evolution of the surface. He postdoc’d at California Institute of Technology (Caltech) via the Jet Propulsion Laboratory (JPL) doing landing site analysis for the Mars Science Laboratory (MSL, aka Curiosity) as well as trained as an Engineering Camera Payload Uplink Lead (ECAM-PUL) for the Mars Exploration Rover (MER) Opportunity. Towards the end of his postdoc, he was hired at JPL as the Geospatial Information Scientist, aka ‘Keeper of the Maps’, and Co-Localization Scientist for MSL. Besides work on MER and MSL, Fred is on the InSight lander science team as ‘Keeper of the Map’ for placement of a seismometer (SEIS) and heatprobe (HP3) as well as doing landing site analysis for InSight and the Mars2020 rover. You can find Fred on twitter at @cirquelar

Introducing Kristin Block

This week, February 24-March 1, 2014, features Kristin Block. Kristin is a planetary scientist at the University of Arizona Lunar and Planetary Laboratory. Kristin works on spacecraft science operations, at the point where science and engineering meet. She is currently a Senior Targeting Specialist for the HiRISE (High Resolution Imaging Science Experiment) camera on NASA’s Mars Reconnaissance Orbiter, where she designs and commands observations of the surface, other spacecraft and landed assets, and the occasional passing comet. She’s proud to be part of the group that has won a NASA team award for its unprecedented images of Mars and new views into how the planet changes with time.

Kristin was a member of the Phoenix Mars Lander Optical Microscope team and has worked in laboratory-based astrobiology, researching the effects of lightning and meteorites on elements necessary for life. Planetary science is Kristin’s second career; before returning to grad school she performed and taught upright bass.

The other 51 weeks of the year, you can find Kristin at @MarsMaven.

Introducing Meg Schwamb

This week, January 27-February 1, 2014, features Meg Schwamb. Meg is an Academia Sinica Postdoctoral Fellow at the Institute of Astronomy & Astrophysics, Academia Sinica (ASIAA) in Taipei, Taiwan. She is a planetary scientist and astronomer interested in planet formation and the evolution of planetary systems including our own Solar System. She is searching for exoplanets with the Planet Hunters citizen science project, which enlists members of the general public to search for the signatures of transiting exoplanets in data from NASA’s Kepler spacecraft. Meg uses the results from Planet Hunters classifications  to explore the frequencies of planetary systems. In addition, Meg is a science team member of  Planet Four , a citizen science project to study the Martian climate  by utilizing human pattern recognition to map seasonal fans on the South Pole of Mars.  Meg also has studied the small body populations of the outer Solar System in the Kuiper belt and beyond. In her spare time, she can usually be found baking and hanging out with her black cat Stella. The other 51 weeks of the year, you can find Meg at @megschwamb.