Walkabout The Galaxy

The Sun is showering us with far more gamma rays than anticipated according to new measurements from a Cerenkov radiation detector in Mexico. The way those gamma rays are produced is very cool. Also cool: data continue to suggest a significant problem with the so-called standard model of particle physics. Muons are misbehaving, and it may suggest a fifth, previously undescribed and unknown, force of nature. Check out all that cool stuff, silly sponsors and trivia, and space news on this episode of Walkabout the Galaxy.

We take a look at two extraordinary astronomical news items in this episode. A deep dive into an astronomical survey has discovered an Earth-sized rogue planet and a Neptune-sized rogue planet. Extrapolating from those discoveries, there may be trillions of Earth-sized rogue planets roaming the galaxy. That's more than the number of stars in the Milky Way! We also explore the question of early galaxies and a model that suggests the universe is older than the standard model. As a bonus, we have some wacky Top quark trivia, space news, and more.

The JWST has spotted water vapor in the hot inner region of a protoplanetary disk, the same region where rocky planets like are own are expected to form. This suggests water can be incorporated into terrestrial planets during formation, without relying on comet impacts. Much, much further away, a new interpretation of JWST results is consistent with dark stars. They are actually quite bright, but are powered by the annihilation of dark matter rather than by nuclear fusion. Catch up on these discoveries, planetary trivia, and much more with your friendly neighborhood astroquarks.

We think of aurora as an atmospheric phenomenon, but what happens when high energy particles from the Sun directly impact a planetary surface? Mercury reveals another cool planetary twist with auroral-like emission from its surface. Meanwhile, Jim and and Josh are gobsmacked by the old news of a big gravitational potential hump in the Indian ocean caused by upwelling of low-density magma far below. Catch up on all the cool space news with the astroquarks.  

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!

That interstellar comet appears to have gotten its odd behavior from the natural rocket effect of hydrogen gas being released near the Sun and not, sadly, alien rocket technology. The universe is still a cool and interesting place, though, and a new clever measurement of stars orbiting black holes shows evidence for a pile-up of dark matter around the black holes, giving us another way to study this mysterious stuff.

Compelling evidence for recent (1990’s!) volcanic activity on Venus has been un-Earthed, or rather un-Venused, by Robert Herrick through analysis of Magellan radar data. A volcanic vent seems to have roughly doubled in size in 1991. We discuss the difficulties of these observations and the implications for future missions. We also take a look at the role of supermassive black holes in controlling star formation in galaxies and have a numerical Top quark trivia. Warning: this episode gets off to a bit of a silly start, so jump ahead to the 24-minute mark if you want to get straight to Venus!

What time is it on the Moon? It turns out the answer to that is not as easy as just lining it up with a time on the Earth. Worse, it's not even that obvious what time it is on the Earth. That's just one of many topics we explore in this episode, including a discovery that the Milky Way is much larger than previously thought, and tracing water molecules from the interstellar medium step by step into that cool glass you have with dinner. Join us for all that, time trivia, and more.

Learn about active asteroids and how the DART mission kind of turned an asteroid into an active asteroid, how impacts into Mercury have given it a dust trail, and we speculate about what might happen if Europa came to Earth. See title for conclusion! It's all about asteroids and dust and impacts on this episode of Walkabout.

Astronomers have sighted a supermassive black hole ejected from its host galaxy and creating a wake of stars from intergalactic gas. And if that wasn't enough to blow your mind, closer to home we've seen organic molecules in the material returned from the surface of a near Earth asteroid. Join us for all this, a weird exoplanet, Apollo program trivia, and some surprising tangents.

Where would you go and what would you bring with you if you could explore any object in the universe? Our cosmologist Jim Cooney wants to look for aliens underneath Europa's icy shell. This shell's complicated fractures may owe something to a new form of ice discovered in a delightfully simple experiment. Further out, a dwarf planet beyond Neptune has a ring unlike any we've seen before, and a delightfully complicated experiment may explain the origin of cosmological magnetic fields.