Posted on by Fraser Cain

Weekly Space Hangout – June 17, 2016: LIGO Team

Host: Fraser Cain (@fcain)

Special Guest: LIGO Team Members:Kai Staats and Michael Landry
Kai Staats is a filmmaker, lecturer and writer working in science outreach. He is currently completing his MSc thesis for his research in machine learning applied to radio astronomy at the University of Cape Town and the Square Kilometer Array, South Africa. Staats was for ten years CEO of a Linux OS and HPC solutions provider whose systems were used to process images at NASA JPL, conduct sonar imaging on-board Navy submarines, and conduct bioinformatics research at DoE labs. In 2012 Staats engaged his passion for storytelling through film. His work includes sci-fi, human interest, wildlife conservation, and science outreach and education. “LIGO Detection” marks Staats’ 3rd film for the gravitational wave observatory that in February announced detection of merging black holes.

Mike Landry is Detection Lead Scientist at LIGO Hanford Observatory (LHO), Washington State. He began working on LIGO in 2000 as a Caltech postdoc at LHO, and has remained there since. Mike has worked on a variety of aspects of the experiment, including commissioning, calibration, and searches for gravitational waves from spinning neutron stars. From 2010 to 2015, he led the installation of Advanced LIGO at Hanford. Prior to working on LIGO, he received his Ph.D. in particle and nuclear physics from the University of Manitoba, for studies in strange hadronic physics at the Brookhaven National Laboratory’s AGS accelerator.

Guests:
Paul M. Sutter (pmsutter.com / @PaulMattSutter)
Morgan Rehnberg (MorganRehnberg.com / @MorganRehnberg)
Kimberly Cartier (@AstroKimCartier )

Their stories this week:
The discovery of a habitable zone “Tatooine” planet

Experimenting with igniting fires in space

1/3 of the world (and 80% of Americans) can’t see the Milky Way

Eight space telescopes are renewed by NASA

We’ve had an abundance of news stories for the past few months, and not enough time to get to them all. So we are now using a tool called Trello to submit and vote on stories we would like to see covered each week, and then Fraser will be selecting the stories from there. Here is the link to the Trello WSH page (http://bit.ly/WSHVote), which you can see without logging in. If you’d like to vote, just create a login and help us decide what to cover!

We record the Weekly Space Hangout every Friday at 12:00 pm Pacific / 3:00 pm Eastern. You can watch us live on Google+, Universe Today, or the Universe Today YouTube page.

You can also join in the discussion between episodes over at our Weekly Space Hangout Crew group in G+!

Posted on by Fraser Cain

Tenth Planet: The Next World in the Solar System

Tenth planet? Artists concept of the view from Eris with Dysnomia in the background, looking back towards the distant sun. Credit: Robert Hurt (IPAC)
Tenth planet? Artists concept of the view from Eris with Dysnomia in the background, looking back towards the distant sun. Credit: Robert Hurt (IPAC)

Before 1930, there were 8 planets in the Solar System. And then with the discovery of Pluto in 1930, the total number of planets rose to 9. Although astronomers kept searching for more planets, it wasn’t until 2005 that an object larger than Pluto was found orbiting in the distant Solar System. This new object was known as Eris, and many considered it to be a tenth planet; but it actually created a controversy that ended up with Pluto being kicked out of the planet club and becoming a dwarf planet. There really is no 10th planet, in fact, we don’t even have a ninth planet any more.

Discovery of Eris

Eris, originally named 2003 ub 313 was discovered by Palomar observatory researcher Mike Brown; Mike has been behind many of the trans-Neptunian discoveries in the last decade. Mike and his team discovered Eris by systematically scanning the sky for objects moving at the right speed in the right object to be in the outer Solar System.

Further observations of Eris showed that it was actually larger than Pluto by a significant amount; it measured 2,500 km across, compared to Pluto’s 2,300 km diameter. And it orbited at a distance of 67 astronomical units, compared to Pluto’s 39 AU (1 AU is the average distance from the Earth to the Sun).

Tenth Planet, Dwarf Planet

Because there was now a larger object than Pluto found orbiting the Sun, astronomers needed to decide whether this would be come the tenth planet. At a meeting of the International Astronomical Union in 2006, astronomers decided to redefine their classification of a planet. And these new rules excluded Eris. Instead of becoming the tenth planet, Eris became a dwarf planet; the same fate as Pluto.

We’ve written many articles about Eris for Universe Today. Here’s an article about how Eris is changing, and here’s an article about how Xena was renamed to Eris.

If you’d like more info on Eris, check out NASA’s page on Eris.

We’ve also recorded an episode of Astronomy Cast that explains why Pluto isn’t a planet any more. Listen here, Episode 1: Pluto’s Planetary Identity Crisis.