Starts With A Bang #50: The Hunt For Planet Nine And Beyond
What lies out there, in the outer Solar System, beyond the orbit of the last known planet? Up until 1992, you would have said Pluto and its moon (maybe “moons” if you were willing to speculate), but even the existence of the Kuiper belt was doubted by many. Of course, all of that changed with the discovery of many different objects, including the more-massive-than-Pluto world discovered in 2003: Eris. We quickly realized that Pluto was not unique, but one member of a distinct class of objects thoroughly different than the planets. In 2006, we created the “dwarf planet” classification for non-planetary objects that still were Pluto-like.
But more recently, a compelling but controversial idea has emerged: the idea of a Planet Nine that is more massive than even Earth, but lies hundreds of times farther away that we are from the Sun. Both of these achievements, the theorizing of Planet Nine and the Pluto-killing discovery of Eris, come courtesy of the same planetary astronomer: Mike Brown. Dive into a fascinating conversation with him and me right here on the 50th edition of the Starts With A Bang podcast!
(Image credit: Caltech/R. Hurt (IPAC))
Starts With A Bang #48 – The Event Horizon Telescope
Earlier this year, 2019, the Event Horizon Telescope collaboration revealed the first image that directly showed the existence of an event horizon around a black hole. This image, constructed from many petabytes of data from telescopes observing the same target, simultaneously, from all across the Earth, provided a breathtaking confirmation of Einstein’s relativity in a realm where it had never been tested before. But that’s just one image of one black hole at one particular moment in time, and there’s so much more to come from the Event Horizon Telescope.
This month, we’re so fortunate to sit down with EHT scientist Sara Issaoun, who takes us through the past, present, and future hopes for the Event Horizon Telescope and how it hopes to answer humanity’s biggest questions about black holes.
(Image credit: APEX, IRAM, G. Narayanan, J. McMahon, JCMT/JAC, S. Hostler, D. Harvey, ESO/C. Malin)
New Podcast: Humanity’s 3 Hopes For Alien Life
There are three very different ways humanity is searching for alien life beyond Earth. We can directly search the various planets and moons in our Solar System for past or present biological signatures simply by sending decontaminated probes, and looking for the evidence in situ. We can indirectly look at distant worlds around other stars, searching for the characteristic changes to the atmosphere and surface that life would bring. And, most optimistically, we can search for intelligent signatures created, perhaps willfully, by a technologically advanced alien species. These are our three hopes for finding alien life, and we’re actively pursuing all three.
Here’s how the different searches work, along with some speculation about what we’re likely to find, and what motivates us to look!
Experiencing A Total Solar Eclipse For The First Time
On August 21, 2017, a total solar eclipse occurred over the continental United States for the first time in nearly 39 years, when half the current US population wasn’t even born. For many of us, it was our first opportunity to ever experience a sight like this for ourselves, and not only lived up to the hype, it was something that even a scientist couldn’t fully anticipate. Here’s a first-person account of what the experience was like, and how to enjoy it to the fullest, yourself, the next time one comes around!
New Podcast: Is Time Travel Possible?
Is time travel possible? Of course it’s inevitable in some sense, as we always move through the Universe at the “boring” rate of one second per second. But what about traveling into the future? If we go, can we ever come back? And what about back in time? Would it be possible to alter the past, or revisit a historical event as an observer?
The mathematics of relativity opens the door to a lot of possibilities, but the physical Universe has a lot to say about it, too. Find out on the latest edition of the Starts With A Bang podcast!