Walkabout the Galaxy

Nature has provided us with exquisitely accurate clocks in the form of pulsars, those rapidly rotating neutron stars whose beams of radiation act like high-powered lighthouses across the galaxy. We discuss the amazing discovery of a deep, low, rumble of gravitational waves across the universe by analyzing the periods of 79 of those pulsar lighthouses. Closer to home, there's evidence for a major climate shift on Mars 400,000 years ago that lines up with changes in Mars's spin. Check it all out on this episode of WtG, with wave trivia and space news too.

Top quark has a field day in this episode with a model for fuzzy dark matter, new data that could shed light on dark energy, and a cool x-ray echo from the supermassive black hole at the heart of our galaxy. Closer to home, we take a look at how JWST is helping us determine if exoplanets have comfortable greenhouse effect atmospheres. Plus, we have a surprising spaceship trivia question and a space travel stumper.

New analysis of radioisotopes of meteorites and the Earth suggest the Earth formed in only a few million years via a process called pebble accretion. This may mean the Earth's water was incorporated early and gradually rather than through late impacts. Recent determinations of the historical length of the Earth's day suggest it stalled out at 19 hours for a cool billion years, and we still have a ways to go to get to 25 hours when we can all sleep in. Find out about the Earth's history, supermassive black hole mergers, and syzygy trivia.

There's a bright supernova in a nearby galaxy, and a very distant supernova made brighter by the beauty of gravitational lensing. In another galaxy, a gargantuan black hole is revealed to be orbited by another supermassive black hole, resulting in a gamma ray flares as it rips through the main black hole's accretion disk. Closer to home, we learn about new asteroid missions and a rapidly warming planet (hint: it's ours). Plus: Harrison Ford and Leonard Nimoy trivia!

Lefty astroquark Jim Cooney leads us on an exploration of what it means for the universe to have chirality. In other words, is there a break in parity in the way galaxies are distributed, or would the universe look the same if we saw its mirror image? The answer and its possible explanation are fascinating. And Josh gets to once again talk about one of his favorite topics, Saturn's rings, and new results on their age.

We take a deep dive into the origin of Mars's moons and whether they are chips off the old block. There's no research to explain the mystery of why Mars and the rest of the planets are even here after billions of years, when the solar system seems to be inherently unstable. And astronomers may have caught a star in the act of gobbling up a planet in the first stages of the star's death throes. Catch up on these scary things that can happen to a planet, space news, and Top quark trivia.

We explore the strange ring system of dwarf planet Quaoar, and discuss a new study that suggests that Uranus's four largest moons (which aren't really very large!) may have subsurface salty oceans. In the astrophysical realm, black holes may have emerged from the chaotic soup of energy during the inflation era when the universe was not even minutes old. Add to that some nerdy computer trivia and you've got yourself another episode of Walkabout the Galaxy!

New calculations show how large impacts onto Mars may have boosted its greenhouse effect, helping explain how it was warm enough for all those rivers and lakes billions of years ago. If that explains Mars' early warm climate, it could be bad news for potential for life there. Futher from home, dust has been observed star forming regions in the Small Magellanic Cloud where the abundance of planet-building raw materials is low. Check out these stories, space news, and special top quark trivia.

We return to Orlando Nerd Nite for a live recording where we take a look at the exciting upcoming missions to the Moon and the ESA mission to Jupiter's moons, JUICE, now on its 8 year journey to its destination. We revisit the amazing image of the supermassive black hole in the galaxy M87, now even amazing-er thanks to the clever implementation of artificial intelligence by some good old fashioned human intelligence.

Space reporter Brendan Byrne becomes an honorary astroquark at MEGACON 2023 where we take a look at some of the recent and landmark discoveries of JWST, including the earliest supermassive black hole and a new era of studying exoplanets. Plus: Anime trivia!