Astronomy Behind the Headlines: A Podcast for Informal Science Educators

"What does the Moon mean to you?" is the theme for this year's International Observe the Moon Night on October 8, 2011. Our neighbor in space has always fascinated us, both culturally and scientifically. Starting with the first human steps in 1969, six of 11 Apollo missions landed astronauts on the Moon to do a variety of science experiments, which continue today. For example, the Apollo lunar laser ranging experiment still exists, with scientists aiming lasers at reflectors on the Moon to measure its distance from Earth. The Lunar Reconnaissance Orbiter, LRO, has sent back highly detailed images showing the locations of those first missions and the science lab equipment that was so much a part of humanity's first steps off our home planet. Scientists continue to explore the Moon, to understand its physical structure, and they plan to use it for future research in astrophysics and cosmology. In this episode of Astronomy Behind the Headlines, Dr. Jack Burns, of the University of Colorado's Lunar University Network for Astrophysics Research (LUNAR), joins us to talk about lunar exploration and some exciting work his team is planning to do from the surface of the Moon.

This summer, several monster outbursts have erupted from the Sun. They released clouds of plasma that occupy a volume of space hundreds of times bigger than Earth. These blasts -- called coronal mass ejections -- emanate from active sunspot regions. If Earth were in their path, these huge eruptions could have had devastating effects on our power and communications systems, and on our satellites. Our planet dodged the danger, but the outbursts are a reminder we live with a variable star that can get pretty active from time to time. We are now headed into a time of increased solar activity. Scientists now have more capability to study and monitor activity on the Sun, including satellites such as STEREO and the Solar Dynamics Observatory. These space-based solar observatories are helping to revolutionize our understanding of our nearest star, and hopefully anticipate and mitigate the influence it has on our planet -- and our technology. With guest Dr. Phillip J. Erickson, MIT Haystack Observatory.

The first stars and galaxies began forming several hundred million years after the Big Bang. Astronomers are now able to probe back almost that far – to study the light from these distant objects. Among their major tools of exploration are the images and data in large surveys taken using the Hubble Space Telescope. The upcoming James Webb Space Telescope will be able to look back even farther in time to see the births of those first stars and the creation of the earliest galaxies. In this episode, we explore the galaxies in the early universe and find out how astronomers know what they know about these very distant objects. With guest Dr. Rogier Windhorst, Arizona State University.

Astrobiology concerns itself with life in the universe. Astrobiologists and planetary scientists want to know if other planets could support life -- and what the evidence for such life might be. By delving back into cosmic time they can understand how the elements for life originated and how they are distributed throughout the cosmos, creating the chemical origins for life. With guest Dr. David Grinspoon, Denver Museum of Nature and Science.

From time to time "guest stars" have appeared in the sky, at times shining bright enough to see during the daytime. We now know the "guest stars" are gigantic stellar explosions called supernovae. A supernova is the final explosion of a giant star coming to the end of its life. In a desire to understand supernovae, astronomers seek them out, hoping to learn more about how the universe is seeded with the raw materials needed for new stars, planets, and ultimately life. In the second part of this special two-part edition of Astronomy Behind the Headlines we talk with Dr. Alex Filippenko about some current research and findings about supernovae.

From time to time "guest stars" have appeared in the sky, at times shining bright enough to see during the daytime. We now know the "guest stars" are gigantic stellar explosions called supernovae. A supernova is the final explosion of a giant star coming to the end of its life. In a desire to understand supernovae, astronomers seek them out, hoping to learn more about how the universe is seeded with the raw materials needed for new stars, planets, and ultimately life. In the first part of this special two-part edition of Astronomy Behind the Headlines we talk with Dr. Alex Filippenko about some current research and findings about supernovae.

First detected in 1967 by satellites searching for the signatures of nuclear weapon detonations in space, gamma ray bursts, or GRBs, are extraordinarily luminous events visible in only the highest energy end of the electromagnetic spectrum. Since then, scientists have speculated about the origin of these distant and highly energetic events. Recent observations have provided enough information for astronomers to figure out what some of the GRBs are. With guest Dr. Dale Frail from National Radio Astronomy Observatory.

Over the past decade and a half, astronomers have used both ground-based and space-based telescopes to discover more than 400 "extrasolar" planets. The Kepler space-based mission uses a technique called transit photometry to search for these planets. In January 2010 the Kepler mission team announced the discovery of five new planets. Four of them are massive worlds similar in size to Jupiter; the fifth is smaller, more like Neptune or Uranus. The ultimate goal of the Kepler mission is to search out the existence of Earth-like planets. With guest Dr. Natalie Batalha from San Jose State University.

The Milky Way Galaxy has a black hole at its heart -- an object called Sagittarius A* (pronounced A-star). We can’t see it visually, but radio astronomers can easily spot it. A group led by Dr. Shep Doeleman at MIT’s Haystack Observatory made a startling measurement of the accretion disk around Sagittarius A*. In this edition of Astronomy Behind the Headlines we talked with Dr. Doeleman about his team’s discovery.

On July 19, 2009, Australian amateur astronomer Anthony Wesley spotted a dark-colored scar high in the clouds over Jupiter’s southern polar region. It looked like the scars left behind by Comet Shoemaker-Levy 9 when its shattered fragments crashed into Jupiter in the summer of 1994. Dr. Heidi B. Hammel is one of the astronomers who have studied the aftermath of this latest collision to learn about how Jupiter’s atmosphere responds to such collisions. In this episode, Dr. Hammel discusses what her team learned from their observations of the collision site using Hubble, Gemini, and Keck cameras.

When humans return to the Moon to explore and live on its surface, those future lunar inhabitants will need safe habitats and plenty of water. As it turns out, the Moon may have all the water we need, locked away in ice deposits at its poles. Today, NASA’s Lunar Reconnaissance Orbiter (LRO) and the Lunar Crater Observation and Sensing Satellite (LCROSS) are allowing scientists to search for water at the lunar south pole. In this episode, we hear about this water-hunting expedition from Brian Day, the education and public outreach lead for the LCROSS mission.

In this episode with guest Dr. Peter Jenniskens of the SETI Institute, we explore those things that go "flash" in the night sky -- and often are romantically called "shooting stars". In reality, of course, they're not stars but "meteors". Now, meteors are not part of our weather, as people used to think, but are usually caused by pieces of rock that arrive from space at incredibly high speeds and collide violently with the air. These meteoroids can be as small as a grain of sand all the way up to a good-sized boulder and often come from streams of dust particles created by comets as they travel around the Sun. We'll also discuss other forms of cosmic debris, such as asteroids.

This episode with guest Dr. Chris McKay from the NASA Ames Research Center talks about astrobiology and the search for life in the universe. Living things have been found in very extreme environments on Earth, like hot springs, or near underwater volcanoes, or hidden beneath the Antarctic ice pack, or even inside rocks. Could life exist in those same kinds of places on other planets? When we look for signs of life on other worlds, what would we look for? How do we search it out? And, how would we know if what we find is caused by living things -- or some other physical process?