Tod Lauer

We don't know what happens at the singularity, indeed that's where general relativity break down. But a black hole is defined by its horizon, which does get bigger with interior mass.

Sure, but I may not be able to answer it.

And your note has just reminded me I something really weird in an image I found last week that I need to run down...

This is a rule I live by. I've seen what happens if you don't do this.

You might enjoy the end of my thread...

Arp wanted world-shattering unknown physics. He had no interest in conventional explanations. At a fantastic conference on mergers in 1989, there was gobs of beautiful work on Arp objects. Arp got up at one point and huffed, "I didn't intend my Atlas to be used this way!" 6/n

But an odd coda. Observers heavily studied the objects. The consensus was that we were seeing mergers, starbursts, tidal interactions of myriad phases/strengths. The Arp galaxies were a treasure trove for understanding the formation and evolution of galaxies. But he was having none of it. 5/n

before CCDs. What were all the weird tailed things? All those plumes, distortions, companions, apparent interactions? Toomre & Toomre was in the future. Arp and Sandage were fellow graduate students at Caltech in the 40s. I think Arp was teasing Sandage,"Hey, Al! Fit this in your sequence!" 4/n

A different picture emerged. The Hubble Atlas over exposed all galaxies in their centers, stuffed them all into the Hubble sequence, and excluded oddballs from the club. Galaxies weren't quite so neat, and were full of goodies poorly glimpsed in Hubble's old prints. But Arp knew this decades... 3/n

The Arp Atlas was a fantastic twitting of Sandage's classic "The Hubble Atlas of Galaxies." The Hubble atlas is a classic and in the time was where I and others learned what they looked like. But it was all too neat and prissy. When in the 80s we started looking at galaxies with then new CCDs. 2/n

The Hubble Arp Galaxy Survey The Hubble Arp Galaxy Survey, Dalcanton, Julianne J., Durbin, Meredith J., Williams, Benjamin F.

This will be an instant classic. I'm wondering what paper I can throw together as an excuse to cite it.

Although the Arp Atlas was published in the ApJ Supplement in the 60s, you really had to get the book atlas itself, comprising bound photographic prints. 1/n
iopscience.iop.org/article/10.3...

What are you talking about? Papers are only for writing and metrics, not reading.

Five moons, sub-surface water ocean, sea of convecting N2 slush, glaciers, hazy atmosphere, volcanic activity.

The density of liquid methane is only 0.42, so I think you would find that rather difficult.

Titan would be in the top three for me. After all the work I did on Pluto, I would love to tool around there. Then there’s Io.

You can fly on it by your own power.

So sorry for your loss...

Comic. [Person 1 talking to a person with shoulder-length hair and a person with a white hat.] PERSON 1: I would never get an electric vehicle. Sure, they sound great, but what do you do if the battery runs out of charge? [caption] I felt pretty silly when someone finally explained tome that EVs are rechargeable.

Electric Vehicles

xkcd.com/3214/

I had guessed “galaxy”

I remember that from the time. It was spectacular and imaginative. And hey!! They discovered that Jupiter had rings by looking back on the night side! That was a real shock!

FOGS!? That’s like packing an umbrella with you when you go up to the mountain…

IIRC that was about the time of the Voyager flyby, so parallel ground observations would have been of value. I didn’t know that you ever did planetary astronomy, though!

Two weeks! That’s always his go to line when he needs an interval to forget about something.

A common solution to the Fermi Paradox is to say, "Hey, ETI is all over the place, but all will destroy themselves after a few 100 yrs. with 100% probability." The only non-depressing answer is that we are largely alone.

Remember a star.

What? Really?

NASA Announces Plan To Bring Wi-Fi To Its Headquarters By 2017 HOUSTON—NASA administrator Michael Griffin announced during a press conference Tuesday that the space agency is launching an ambitious mission to make Houston’s Johnson Space Center wireless-Internet ...

This remains one of my all time favorite Onion articles. theonion.com/nasa-announc...

Sorry - looks like I was flat out wrong about the centaurs...

Ahh... I need to go back to my texts! I had incorrect thought that the centaurs provided the final Delta-V.