@PearsonArtPhoto ah, that's the answer...

lol

nature.com/news/…

Software error made Hitomi spacecraft fire thrusters in the wrong direction; spin out of control and breakup

zzzZZzz

@kimholder I do a lot of things with the boy scouts. Sometimes I get to do something really cool as a result of helping out. This is by far the coolest thing I'll have gotten to do (But I've had a few other cool things too)

@called2voyage The problem with no detailed research effort is, that I don't know what exactly he wants to know. Does he need an explanation of what ISP is? Does he want to know about (as you suggested) maintenance problems? These are very different questions. If you want to go out on a limb and guess at what he might have meant and spend your time answering with something that maybe he either already knows, or can't yet understand, by all means. I won't vote to close.

@called2voyage Sorry, I over-read the word "Maintainance". It wasn't in the question title at first. So that makes the question a lot more sensible.

@called2voyage Still, does he mean maintenance as in "upkeep" or "maintenance" as in "durability".

i'm not sure what to make of the question, actually. i would have thought that it is in a prototype stage and maintenance benefits could not yet be known.

Well, there is the point that the compressor would be exposed to a hard vacuum. Since it's probably oil-lubricated, this certainly spells trouble.

Anyway, I think the question needs work

@Rikki-Tikki-Tavi You make a good point about spelling out what he has in mind with "maintenance"

Maybe we need a comment honing in on that

If this becomes a useful question with a useful answer, it's all I'm hoping for.

@Rikki-Tikki-Tavi thanks for working with me on this

I didn't say I was, but ok :/

That's not what I meant. I just mean thanks for talking through it here

i'm very curious about that engine, it would be nice if we had more questions about it. I don't even know how to ask though.

:)

i did a quick search, there were several new stories last November because BAE invested $30 million

Just saw the same thing.

I'd say they are still around, but lurking for funding...

Ok I take it back, but 30$ isn't anywhere near buying you a rocket engine, let alone a new cycle

30M$

Every launch of the Ariane 5 costs 100-200M€

Development cost not included

yeah, it does look like a long shot at this stage.

i was excited about it initially, when i read about the sub-scale test of the precooler

They have had about $100M total in funding.

That's probably close enough for them to at least get the funding they need to do a ground test.

I'll wait and see, but I won't hope

I'll still hope. Some day it will be a reality.

I am not sure, a lot of money has already been wasted on SSTO. But then again, building an orbital rocket was originally considered pure sci-fi too.

'o

@Hohmannfan Debatable. If panspermia is fact, then we are the contaminants

Is there a gravity map of Sol ?

Hello, everyone! It's been a while

'o @c2v It has indeed )+: Pure carelessness I'm sorry to say

@Everyone I can find mass distribution graphs for portions of the solar system, but not the whole

Hello everyone! (pun maybe intended).

That's for the asteroid belt

This one says it is for the universe:

I take that back. ..I skimmed. It's actually for a galaxy cluster

Anyway, it may not be exactly accurate.

@Hohmannfan right

I wonder if we had the raw data how easy it would be to make the visualization in Matlab

If you have data, it can be visualized in Mathlab. Period.

@Hohmannfan that's why I said "how easy"

As opposed to "could it be done"

hey @Everyone, nice to see you :)

interesting. there are 13 people in this room right now, of which 7 are moderators.

back. 'o@kimholder @Hohmannfan

@kimholder Best to keep a low profile then, in the presense of the overlords.

To quote Churchill, or Hitler, or Napoleon ... or someone about that time

Never have so few been moderated by so many

@Hohmannfan Thou shalt not cower before thine overlords!

@c2v Then there isn't a gravmap for Sol himself?

What's the source for that gravmap of the cluster?

@Everyone just for the sun?

Just for the Sun

@Everyone large synoptic survey telescope website

@Everyone can't imagine it'd be very interesting

@c2v ;) Be nice to have confirmation that it isn't interesting

Physics has a couple answers about mass distribution of the sun

Basically it is the roundest spherical thing nearby, but it's not a perfect sphere

Somewhat oblate like Gaia herself, as I recollect

But not as much

Yep; I'm just wondering how uneven it does get. Do we have instruments capable of measuring the difference?

Google "shape of the sun"

gah; I didn't think of that. My search was for "gravity map sun"

sheesh

"Too hot to touch" is a good summary, though I am not sure I found it at Physics...

Ah. Perfect. Just what I wondered

So they are, or were trying to look for oscillations in the core

Keep in mind: it's still the roundest thing around ;)

Would a larger star be more round due to gravity, or less round due to increased activity?

Sure t is; at 28x of Earth gravity though - even a minor fluctuation should be large though

@Hohmannfan Dunno; "depends"?

"Depends" indeed. I can not tell what is more important. I am posting it on Astronomy.

Yey!

space.com/32748-weird-tailless-comet-oort-cloud-discovery.html

More 'dark' discoveries. This seems to have been the month for dark discoveries ... a hidden satellite, and now this.

"A new dark age for astronomy" had been perfect clickbait.

:D

Say that before Master Yoda, I dare you

me sleep. 'nini

@Everyone bye

Oh, and it's confirmed, Red Dragon, while it is getting some support from NASA, is being completely paid for by SpaceX.

At least, it is not being paid for by NASA.

I've wondered for the last 4 years if SpaceX was going to come up with a mission concept to send humans to Mars and bid it to NASA. I'm really beginning to suspect that is true.