Dr. Jacob Izraelevitz describes how engineers might design a balloon to explore Venus. This work is in the early stages, what NASA refers to as a "Mission Concept." He also explains the challenges of Venusian exploration.
Image: Venusian clouds, as imaged by Pioneer Venus Orbiter. Source.
When taking a sample of the Moon's surface, the Apollo astronauts discovered a sharp transition from powdery soil to harder rock. This transition was entirely unexpected, and remained unexplained for decades. Dr. Ivy Curren talks about an experiment she designed to explain this phenomena. She also tells us about a type of lunar dust formation that scientists call "fairy castle structures."
Dr. Seager explains how she and other astronomers are looking for extraterrestrial life. We discuss the Drake and Seager equations. We also talk about how astronomers might be able to detect life by measuring chemicals in distant planet atmospheres.
Using a model, MIT astrophysicist Sara Seager demonstrates Starshade, under development at NASA’s Jet Propulsion Lab in Pasadena, California. Deployed in space, the device, more than 100 feet in diameter, would block the light from a star. A space telescope would capture an image of a planet when it’s between Starshade’s petals, seeking evidence that life may exist on the planet.
(PHOTOGRAPH BY SPENCER LOWELL / NATIONAL GEOGRAPHIC)
Dr. Alicia Lanz talks about the history of astronomical instrumentation, starting with the first telescope. She describes some bizarre historical telescopes and shares a surprisingly inspirational story about bubbles in glass.
Professor Katelyn Allers talks about how you can discover small cold stars! She is a member of the Backyard Worlds project, which is a collaboration between astronomers and citizen scientists. This project searches for brown dwarfs, which are some of the closest objects to our solar system.
Brent Barbee returns to the show to talk about deflecting asteroids. He explains how an asteroid might react to an impact, and also talks about the proposed DART mission, which would change the orbit of a small asteroid moon.
Dr. Solange Ramirez returns to the show to talk about her new position as Project Manager of the Sloan Digital Sky Survey V. Amount other things, the project will study over six million stars and how black holes change over time. These millions of measurements will be made using a robotic telescope system that is currently being built.
Above: Dr. Ramirez, holding one of the telescope robots described in the episode.
Rob Seaman of the Catalina Sky Survey talks about time, and why you need to know the time to discover asteroids and comets. He explains how he installed a highly accurate clock, and makes the case that "natural time" is better than "cold, heartless atomic time."
Above: Self-portrait of Rob Seaman, taken during the commissioning of a spectrograph for calibration purposes.
Dr. Dave Tholen talks about near-Earth asteroids. He explains why they can be difficult to observe, and how he manages to spot them anyway. He also tells the story of a particularly famous asteroid that he discovered, and sets the record straight about its name.
Hear the performance of "Pirates of the Caribbean" here.
Image: Graphic showing the path of asteorid 99942 Apophis changing after a close pass with Earth.
The James Webb Space Telescope hasn't launched yet, but scientists already have plans to use it. Dr. Kartaltepe talks about how she'll use it to study galaxies. She's interested in the first galaxies that ever formed, as well as galaxies at a wide range of distances from Earth.
Urey Prize winner Dr. Francesca DeMeo stops by the show to talk about her asteroid research. She explains what a differentiated asteroid is, and tells us about her asteroid classification system. She also shares a new result, and explains how it may change the way we think about solar system formation.
Dr. Matthew Payne talks about his exoplanet research, which involves looking for periodic dimming in stars. We discuss the Kepler and TESS space telescopes, and he explains why he's so interested in measuring the masses of exoplanets.
Dr. Joanna Carey talks about her research on our home planet, Earth. She explains how the climate change we're experiencing is ten times faster than any in geologic history. We also discuss why small changes in carbon emissions today will make a huge difference to the future climate, and things everyday people can do to mitigate the damage.
Lear more about Dr. Carey’s research here, and follow her on twitter!
Dr. Alejandro Soto returns to the show to talk about how lakes on Titan and on Earth influence the nearby atmosphere. He talks about how lakes create breezes that allow for sailing on Earth, and how the situation changes on Titan.
Dr. Matt Holman, head of the Minor Planet Center in Cambridge, Massachusetts, stops by to talk asteroids. The Minor Planet Center handles about a hundred thousand asteroid observations a night, from observatories all around the world. He talks about the difficulties in linking asteroid observations, and the discovery of the first interstellar asteroid, 'Oumuamua.
Image: A collage of images of the asteroid Gaspra, taken by the Galileo spacecraft. Credit: NASA/JPL.
Dr. Luisa Rebull returns to the show to describe new research with the Kepler space telescope. Her ingenious study takes advantage of Kepler's strengths, and has produced results that stump theorists. Dr. Rebull explains why this data has given her "a whole new appreciation for post office workers."
Dr. Sebastiano Padovan talks about the planet closest to the sun, Mercury. He compares the evolution of planets to movies, and says that understanding a planet's history from its current state is like trying to figure out the plot of an entire movie from a single snapshot. He also explains why Mercury is "a favorite" of scientists who do computational modeling.
Tim Thompson, former JPL scientist and member of the Mt. Wilson Institute Board of Trustees, talks about the Mt. Wilson Observatory. He explains why he doesn't operate the Mt. Wilson telescopes himself, and tells us why astronomers hate the twinkling of the stars. This episode was recorded on location, and Tim talks about the many public events offered at Mt. Wilson.
Dr. Ingrid Daubar returns to the show to tell us about the InSight mission to Mars. InSight carries a seismometer and a self-hammering heat probe, and will explore the interior of the planet. She tells us what it was like to be at InSight's launch, and explains how the mission's landing site was selected.
Dr. Shohini Ghose talks about quantum entanglement, which she describes as an "amazing, weird handshake across space and time." She tells us about quantum information science, which finds useful applications for the weird quantum qualities of particles.