Universe Today Podcast

In this week's questions show I explain how we'll ever study 100 million planets, what's the business case for space exploration, and how I pull the questions together for these shows.

Over the last weekend, astronomy Twitter started noting that the red giant Betelgeuse, the prominent shoulder of Orion was looking visibly dimmer in the sky, and I had a few people reach out to me and ask me if it was really happening and if I knew what was going on.

This is exciting, of course, because Betelgeuse is living on borrowed time, and it could explode as a supernova any day now. Or, it might not detonate for another 100,000 years. We just don’t know.

What’s Betelgeuse up to? Is this a sign that it’s about to explode? And what would it mean if it did?

This week I'm joined by Andrew Rader, a game designer and mission manager at SpaceX. Andrew's new book is called Beyond the Known and it's all about the history and future of space exploration.

As I’m recording this video near the end of 2019, the total number of confirmed exoplanets stands at 4,104. We’ve come a long way since the discovery of the first exoplanet orbiting a sunlike star back in 1995 with 51 Pegasi b.

And the reality is that the race to find new exoplanets is only accelerating. New ground and space-based telescopes are turning up planetary candidates at an increasing rate. New techniques will find planets in entirely new ways. The bottom line is that over the next few decades, this mere 4000ish will multiply by orders of magnitude.

So let’s run the clock forward and try to calculate what the future holds for exoplanets. How many worlds will we know about 3 decades from now, in the year 2050?

How old is the Universe? In order to figure that out, all you have to do is figure out how quickly it’s expanding, and then the clock backward until everything is crunched together.

And astronomers have measured the rate that the Universe is expanding with tremendous precision at various times in its history; at the beginning, and much more recently. The problem is, these expansion rates disagree, but they’ve both been measured so accurately that their error bars don’t overlap.

In other words, there are multiple, highly accurate estimates for the age of the Universe, and they disagree.

In this week's questions show, I explain why I don't think we always need to be realistic, if galaxies in the local group are bound together gravitationally, and what we should call Earth-moving equipment on Mars.

Extending humanity to other worlds in the Solar System is at the very limits of our modern technology. And unless there are dramatic discoveries in new propulsion systems or we learn how to build everything out of carbon nanotubes, the future of space exploration is going to require living off the land.

The technique is known as In-Situ Resource Utilization or ISRU, and it means supplying as much of your mission from local resources as possible.

And many of our future exploration destinations, like Mars, have a lot to work with. Let’s look at the raw materials on Mars that missions can use to live off the land and the techniques and technologies that will need to be developed to make this possible.

In this week's questions show, I explain why you could have a steam-powered rocket, how often spacecraft have crashed into asteroids and comets, and why a red supergiant star actually has a very low surface gravity.

The exploration of Venus has been mainly about getting down to the surface of the planet. The Soviet Union sacrificed lander after lander to discover just how extreme the conditions are down there on the ground.

But higher up, among the clouds, the climate on Venus is surprisingly Earthlike in temperature and pressure, and there have been some fascinating ideas for robotic and human explorers to fly the skies of Venus, to help understand our evil twin planet.

Let’s take a look at them.

This week I'm joined by Jason Derleth from NASA's Innovative Advanced Concepts (or NIAC). This is a special part of NASA that funds innovative ideas for new telescopes, propulsion systems and rovers. Many of the cool, science-fiction ideas I present on this channel come from research done at NASA.

In this week's questions show, I explain why we can see meteor showers every year, why we're not 3D printing telescopes in space, why there aren't any plans to launch telescopes with SpaceX Starship. And a lengthy answer to one of the most common James Webb questions we get: can it be refueled? This was answered by Paul Geithner, a Deputy Project Manager for James Webb during a recent livestream.

In case you're interested, I was the special guest rogue for episode 750 of the Skeptic's Guide to the Universe. This long-running science podcast features all kinds of topics relating to science and skepticism. We talked about recent news in space and astronomy as well as the pseudoscience that I run across in my job. If you haven't already, you should definitely subscribe to their podcast, it's one of my favorites.

https://www.theskepticsguide.org/

We talked about the implications of SpaceX Starship, Starlink, why power beamed from space or asteroid mining will never turn a profit down here on Earth, and why he's not that scared about space radiation.

When it comes to telescopes, bigger is better. That’s true down here on Earth, and it’s especially true out in space. As astronomers and engineers design the next generation of giant space telescopes, they’re running up against the limits of current launch providers. There are only so many ways you can fold a huge telescope to get it to fit inside a 5-meter launch fairing.

The upcoming James Webb Space Telescope is pretty much the very limit of what you can construct on Earth and put into space in a single launch. To go bigger, space agencies will need to consider assembling their next-generation space telescopes… in space.

In this week's questions show, I tackle all the questions about James Webb generated by the videos we did this week. Can it be refueled? How can it see the entire sky? Is the delay a blessing? And more...

Today I'll be joined by Paul Geithner, the Deputy Project Manager for NASA's James Webb Space Telescope. You've had questions about this mission. Well... now's your chance to get them answered directly from the source.

Paul started working with NASA in 1991 on the Hubble Space Telescope, shifting over to James Webb. In 2011, he became the Deputy Project Manager, Technical for James Webb.