No, we are on 30 acre plots out here in the Texas hill country. He lives in San Antonio and has the place next door specifically so he can test his rocket motors.

We run goats on our place because there is a tax break that turns the property tax bill from thousands into hundreds. The goats actually came with the property. They are so much fun:

https://i.imgur.com/WTvcHUo.jpg

It has a tail coming from the ground and is clearly moving upwards.

Unidentified in the literal sense, sure. But as it’s colloquially used… you’d have to be a real smooth brain operator to infer this is anything other than a rocket.

Not to mention 7 launches in December alone.

https://en.m.wikipedia.org/wiki/List_of_Falcon_9_and_Falcon_Heavy_launches

Brilliant. I love when 'regular' folk do stuff like this. I just hope you are in the country and not in row houses..... I wish him tons of luck.

It wasn't unannounced, they told everyone when they lit it off...

Just recently reconciled those two concepts myself. Lots of "the same stuff but with different words" in black hole physics.

I just wanted to find an easy way to die. What is easier than just hanging out at an event horizon?

If you double the mass of a black hole, its gravity doubles. But its radius also doubles. Gravity decreases with the square of the radius, so at double the radius, you have 1/4th the gravity. So double mass of the black hole, and you get 1/4th of double the gravity, or 1/2 the gravity at the event horizon. But the tidal forces that cause spaghettification decrease with the cube of the distance, so you get 1/2 the gravity and 1/4th the spaghettification. Make a black hole 10 times bigger, and you'll get 1/10th the gravity and 1/100th the spaghettification at the event horizon.

The black hole Sagittarius A* is about a million times more massive than a typical (stellar) black hole, so it's gravity at the event horizon is a million times smaller, and the spaghettification will be a trillion times smaller. Not sure if it's enough to survive being spaghettified near the event horizon, but a trillion times less stretching can't hurt. Black holes a thousand times more massive than Sagittarius A* exist in other galaxies, so they'd be even easier (a million times easier) to survive falling into. (Actually, there are a few known black holes about 10,000 times bigger or more than Sagittarius A*.)

More than a launch per week. It's hard not to be in awe of what SpaceX has accomplished.

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Ok. I don't think you're discussing in good faith here.

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>Sure, but Carl Sagan has been listed as an author in a decent pile of papers even before he was very famous.

sure?

you know nothing my friend, until your name appears in the author line. Amirite?

I know the basics of the process! I'm not a researcher, but I've studied in universities and have many researcher friends and colleagues.

haha ha

you know nothing of the process? I have friends?

please

until your name goes on the author line, you know nothing. IMHO

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Depends. Impulse and specific impulse are equally viable to talk about when comparing rocket motors.

I had never seen that expression before. I suppose it would be. Thanks for pointing me to that.

Got you my friend, my message is, make a pleasant impact while enjoying it. Leave UFO-s to those who think this is the pinnacle of their life they can achieve.

Which doesn't make much sense if you start making your payload increasingly expensive just to get the launch mass down.

Better design a heavy lift reusable system with an "oversized" payload capacity but relatively low launch price.

If you have to shave off mass off your payload your inevitable will add billions of costs. But if you can double the mass of your payload while keeping the requirements the same your development costs gets down fourfold.

Using nuclear engines just to make the payload a few hundred kilograms lighter would the the pinnacle of ineffectiveness. Sure, kg by kg your mission might be more "efficient" but your budget has grown exponentially.

We really have to let go of the idea that we nedd to count kilograms in our mission planning. Better just add the masses of everything you need in the end and then just launch enough propellant to get you where you want to go.

By doing this we could massively increase the science per dollar we get out of every mission.

I mean.. it technically was a UFO. It was an unidentified flying object. Doesn’t always mean aliens. They just didn’t know what it was

There's a great episode of Star Talk Radio in its earlier years and they cover all this.

Is that because black holes are a localized end of the universe?

You know UFO doesn’t HAVE to mean aliens right? Could be a foreign device etc

>No one repairs rocket engine especially back then

Right. Not even after a static fire test.

But one idea was to use NTR tech in a reusable space tug. Reusability is very difficult to achieve if you can't even maintain your engine.

With that limitation NTR was confined to single use missions. Like pushing something to Mars and then getting deposited in a solar orbit.

But for such a use case NTR doesn't offer much advantage over LH2/LOX. The tanks need to be enormous, they need heavy insulation against boil-off, the NTR engines need heavy shielding, thrust is low, etc.