Title: Extremophiles: How do they do it?
Description:
Over the past 4 decades, our knowledge about life that can flourish under extreme conditions has dramatically expanded. Psychrophiles can metabolize down to -25°C, while hyperthermophiles grow at up to 122°C. In the deep ocean, piezophiles have been found living under pressures of >110 Mpa. Life under other marginal conditions such as high salinity, extremes of pH, desiccation, and radiation, as well as combinations of stressors, has now been found.
Information about extremophiles is relevant for biotechnological applications, bioremediation, and in our search for life elsewhere in the universe. Some scientists argue that proteins adapted for high temperature or pressure will be stiffer than those that operate under freezing conditions. Others argue it is not so simple.
To settle this debate, we are planning to examine a set of small proteins called rubredoxins by multiple techniques to compare their dynamics at different temperatures. Rubredoxins (Rds) are the smallest of all Fe-S proteins – with only about 55 amino acids, their simplicity makes them an ideal system for testing theories about protein structure.
This project will involve comparing x-ray diffraction and NMR data on rubredoxins as a function of temperature, to see if the predicted differences in flexibility do in fact exist. For the student with a computational bent, normal mode and molecular dynamics calculations will assist in interpretation of the data. Depending on scheduling, there may be an opportunity to assist in diffraction experiments at the Stanford Synchrotron Radiation Laboratory, and/or in NMR experiments at UC Davis.
Qualifications:
The ideal candidate would have at least one year each of chemistry, physics, and some knowledge of biochemistry. Familiarity with Mathematica and/or bioinformatics software would be a plus but is not essential. This project is suitable for a student interested proteins and life under extreme conditions.
Description:
Planetary rings can exist close to the planet where the tidal forces prevent formation of moons. Over time, rings can spread and think out, with the outer edge giving rise to moons which hen migrate out through interactions with the ring. Over longer timescales, the moons migrate due to tides they raise on the planet. Depending on planet's rotation, it is possible for planets to be caught in a ring-moon cycle (proposed by Hesselbrock and Minton 2017), in which a planet alternates between having moons and rings. This kind of cycle requires a relatively slowly-rotating planet, and may have happened in the past to Mars and Uranus. As many close-in exoplanets are thought to be tidally spun down by their stars, they may be susceptible to ring-moon cycles. Ring-moon cycles may offer a mechanism to produce youthful rings around billion-year-old planets, which may be detectable trough transits.
Qualifications:
Experience with classical mechanics above freshman level is preferred, and some computational experience (any high-level programming language) is a requirement.
Requirements:
Background in physics and interest in theoretical work.
Description:
Dr. Ginny Gulick examines erosional features on Mars, looking for the tell-tale signs of running water in Mars’ geological history. Some of the meandering valley networks that lace the landscape may indicate that Mars was a warmer, wetter world billions of years ago. But other features, including gullies found around many impact craters and valley walls, may be evidence of water that flowed on the martian surface more recently.
Dr. Gulick uses stereo images and Digital Terrain Models (DTMs) from Mars-orbiting cameras including HiRISE, CTX, and HRSC to look for features caused by flowing water (“fluvial” features) or by heated groundwater (“hydrothermal” features). The current project is focused on understanding gully formation in Mars’ more recent geological history, by studying their 3D slope morphology, their spatially-associated landforms, and their topographic and environmental settings. However, we are also interested in understanding the formational environments of channels, valleys, and paleolakes throughout Mars’s geological history. We will use information from terrestrial analog sites, hydrologic models, and DTMs to estimate water discharges, volumes, and erosion rates to better understand the implications for paleoclimatic change.
Qualifications:
Students with a geology, geography, or hydrology background with an emphasis in geomorphology and experience with computer software ArcGIS and/or ENVI are strongly desired. Experience with Python and/or MatLab preferred.
Description:
Caves represent unique micro-environments on Mars in which the conditions lethal to Earth-like life that prevail at the planet’s surface become mitigated: caves offer shielding from stark day-night temperature variations, micro-meteoritic bombardment, and ionizing radiation from deep space and the Sun. Possibly, many caves on Mars may also harbor H2O (liquid water or ice), making them of major interest for astrobiology.
Over 1,000 caves, pits, and other discrete deep depressions have now been inventoried on Mars. Most are found in Mars’ two major volcanic provinces, Tharsis and Elysium. In the years ahead, robotic missions are anticipated to begin exploring Mars’ caves, to be followed eventually by astronauts. But which cave(s) should we explore first? The student will work with Dr Lee to identify and prioritize, using in particular the Mars Quickmap, Mars Trek, and Google Mars data visualization and analysis tools, optimum candidates for future robotic and human cave exploration on Mars.
Description:
Supernovae play a key role in the chemical and cosmic dust budget of galaxies, producing heavy elements and dust in their ejecta and processing dust. These explosions light up regions of stellar birth, trigger the next generation of star formation, return solid material to the gas phase, and create the elements necessary for life. The origin of cosmic dust in the early Universe after the Big Bang has long been the subject of considerable debate. Supernovae from massive stars could be the major source of that dust.
Infrared imaging and spectroscopy provide direct information on the composition, amount, and distribution of molecules and dust in supernovae and their remnants. This project is to study molecule and dust formation in supernova-ejecta and the heating and cooling of gas by using ground-based near-infrared observations of varied samples of supernovae in nearby galaxies. The student will work on optical data from a robotic network of optical telescopes - Las Cumbres Observatory (https://lco.global/) and near-infrared observations using IRTF (https://irtfweb.ifa.hawaii.edu/), 8-meter Gemini (https://www.gemini.edu/), or 10-meter Keck (https://www.keckobservatory.org/) telescopes. A particular emphasis will be data analysis of NIR spectroscopy of IRTF, Gemini, or Keck data. Additional data analysis may be performing photometry of optical imaging data. The student can have opportunities to participate in remote observing runs if the student has a strong motivation.
Qualifications:
The ideal candidate would be an enthusiastic student interested in possibly pursuing a post-graduate career in astronomy, physics, or chemistry by building a research experience through this astrochemistry project. We expect the student to have taken introductory physics and chemistry courses. Experience in Python, IDL, or high-level programming language is preferable but not required.
Title: Searching for radio technosignatures with the Allen Telescope Array
Description:
Radio waves are low-energy, travel at the speed of light, and are not blocked by gas and dust. For these reasons (among many others), it is hypothesized that extraterrestrial intelligences (ETIs) might use radio transmitters to send signals across the galaxy. We might be able to detect these radio “technosignatures” using radio instruments such as the Allen Telescope Array (ATA). In this project, the REU student will select a set of technosignature targets and observe them with the ATA. The student will then use existing software such as bliss or SPANDAK to perform a novel, in-depth technosignature search of those targets, with the goal of setting novel upper limits ever for the chosen targets (or detecting ETI!).
The student will complete a discrete observing project over the course of the summer, including planning an observing campaign, executing observations at HCRO, and analyzing data. They will work primarily at the SETI Institute in Mountain View, but will also have the opportunity to travel to Hat Creek Radio Observatory to get hands-on experience with the ATA.
Description:
This is literally a SETI Institute project to find patterns of lights in the sky! The Geostationary Lightning Mapper (GLM) instruments onboard the GOES 16, 17, 18 and 19 weather satellites are designed to detect lightning, but they can also detect other bright flashes in Earth's atmosphere. We have developed a machine learning based exploding meteor (i.e. bolide) detection pipeline as part of the Asteroid Threat Assessment Project (ATAP) funded by NASA's Planetary Defense Coordination Office (PDCO). With the pipeline running for numerous years now, we have assembled a vast and unique catalog of bright meteors using a consistent and wide field of view. This project will involve studying the statistical distribution of bolides in our data set. Can we find patterns in these bolides? Can we find clusters of bolides, possibly multiple events from a single fragmented object? Are all the bolides evenly distributed across the globe? c