Ep. 200: The Mariner Program
The first interplanetary series of missions was the American Mariner program. These successful spacecraft visited Mercury, Venus, and Mars, and laid the groundwork for the US missions to the outer planets. Let’s take a look at the program and their incredible accomplishments.
Ep. 199: The Voyager Program
Launched in 1977, the twin Voyager spacecraft were sent to explore the outer planets: Jupiter, Saturn, Uranus and Neptune. Because of a unique alignment of the planets, Voyager 2 was the first spacecraft to ever make a close approach to Uranus and Neptune. Let’s take a look back at this amazing program, and see where the spacecraft are today.
Ep 198: How is a Space Mission Chosen?
Space missions are expensive to build and launch, so there’s a lot of planning that goes into choosing exactly what’s going to be shot into space. Space scientists and engineers recently went through the process of deciding on their science goals, so we thought we’d spend an episode explaining how this works, and how the next generation of spacecraft and telescopes will be selected.
Ep. 197: Astronomy Cast Live from Dragon*Con 2010
In this special live Dragon*Con 2010 episode of Astronomy Cast we welcomed special guest Les Johnson, Deputy Manager for NASA’s Advanced Concepts Office to talk about the state of human space exploration. And then we opened up the show to some amazing questions from the audience. Listen to the first live show ever done with both Fraser and Pamela in the same room.
Ep. 196: Luminosity and Magnitude
Astronomers measure the brightness of stars as magnitude. But this brightness depends on the distance to the star as well as the total amount of energy it’s pumping out into space. And from our vantage point here on Earth, appearances can be deceiving.
Ep. 195: Planetary Rings
Saturn is best known for its rings. This huge and beautiful ring system is easy to spot in even the smallest backyard telescope, so you can imagine they were a surprise when Galileo first noticed them. But astronomers have gone on to find rings around the other gas giant worlds in the Solar System – the differences are surprising.
Ep. 194: Dwarf Planets
In 2006, the International Astronomical Union demoted Pluto out of the planet club. But they also started up a whole new dwarf planet club, with Pluto, Eris and the asteroid Ceres as charter members. Let’s find out what it takes to be a dwarf planet, and discuss the current membership.
Ep. 193: Astronomy with the Unaided Eye
We talk a lot about telescopes here on Astronomy Cast, but you really don’t need any special equipment to appreciate what the night sky has to offer. Just head outside with some sky charts, maybe a planisphere, some friends and hot chocolate, and you’re good to go. Let’s talk about what kinds of things you can see with just your eyes.
Ep. 192: Chandra X-Ray Observatory
The Chandra X-Ray Observatory is the third of NASA’s Great Observatories, sent into space aboard the space shuttle to view the Universe in high energy X-ray radiation. This is the territory of supernovae, supermassive black holes and neutron stars; some of the most extreme places in the Universe.
Ep. 191: Chandrasekhar
The first half of the 20th Century was a productive time for astronomy, with theorists working out much of the science that we take for granted today. One of these astronomy stars was Subrahmanyan Chandrasekhar, who determined the maximum mass of a white dwarf star.