Monday, February 24, 2014 - Geophysicist Kaustubh Thirumalai explains how the Earth has changed temperature over the last 11,000 years. Climate change is real.


Geophysicist Kaustubh Thirumalai (@holy_kau) explained so much about the world we live in, and how it has been changing in time.  Over the last century, physical chemists like Harold Urey figured out that the relative abundances of isotopes were sensitive to the local temperature.  Kaustubh has applied these so-called 'proxies' as ways to indirectly measure the temperature and salinity of the ocean.  These measurements go back to the last 10,000 years (aka. the 'Holocene' - in between glacial worlds). Why was it hotter or colder in the past?  What will the climate be like in the next 100 years?  About 56 million years ago the world had a period of enhanced warming, which gives us an imperfect analog to the modern climate. Kaustubh breaks down the fact that the vast majority of scientists are in accord about anthropogenic climate change.


Monday, February 17, 2014 - Astronomer Klaus Pontoppidan educates us about planet formation.


Astronomer Klaus Pontoppidan visited us in the studio this week from the Space Telescope Science Institute (STScI), in Baltimore, MD.  Klaus is attacking questions about the origins of life, and how planets form around stars.  He is one of the foremost experts in infrared astronomical spectroscopy and the detailed chemistry of the birth sites of planets.  Specifically, he has detected water in the form of either gas (water vapor), or ice (frozen water).  Back on Earth, there are still remnants of the 4.6 billion year old solar protoplanetary disk.  These shards of pristine and processed rock (rarely) rain onto our homes in the form of meteorites.  Klaus gives us advice on where to look for these meteorites so we can sell them on eBay.  We wrap up with a discussion of the James Webb Space Telescope (JWST), and how this and other technologies will dramatically improve the detail with which we can examine distant planets.


Monday, February 3, 2014 - Dr. Joel Green observes outbursting young stars.


Dr. Joel Green's vivid descriptions of the observations of young stars bring to life the details of the star formation process.  Joel answers questions about how long it takes planets to form, and how to look for disks around stars.  The disks around stars are hotter closer into the star, and colder farther away from the star.  Using infrared-sensitive detectors connected to telescopes, astronomers like Joel and cohost DJ Gigayear discover properties of disks surrounding young stars.  We break down the different classes and types of protostars.  Joel describes his work with the Spitzer Space Telescope and the Herschel Space Telescope.  One of the things Joel is trying to figure out is the effect of chaotic sudden burst events seen in stars like FU Orionis.