SpaceX And/Or Rocketry In General

archae86
archae86
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RE: So you are saying that

Quote:
So you are saying that to launch something from the ISS, for example, towards the Sun, and have it actually get there, would take a HUGE rocket motor?


Earth goes around the sun at about 30 km/sec.

If you fire your small rocket forward, the new orbit will have as its highest point earth's orbit, but the lowest point will be just a little closer to the sun. If you actually want to get to the sun itself in one burn, you are responsible for providing a delta-V of 30 km/sec. For reference, earth escape velocity is only 11.2 km/sec. So a sun dump trip from ISS orbit would require not just a huge rocket, but a multi-stage one.

So the mass ratio between total vehicle and payload required for a "sun dump" by direct path is exceedingly high, though you could trim it down by using a very high specific impulse engine (most likely ion propulsion in the current catalog), or by detouring past some convenient masses (more commonly known as Venus and Mercury) to get some gravity assist. It would still, however, be a big, expensive, (and with those trims very long) undertaking, not resembling the simple very small booster first mentioned at all.

Mike Hewson
Mike Hewson
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So what I did was get this

So what I did was get this shot :

and turn it into a 2000 piece jigsaw, 68 cm x 96 cm, for my son's birthday. There's a number of mobs that will do this for you, I chose puzzlesprint.com and had it delivered ( from Latvia via DHL ) for ~ $120 AUD all up.

Peter is right. To fall into the Sun you have to clip a 30 km/sec tangential 'gift' that you get automatically by launching off Earth. You can knock 1 km/sec off that by launching at midday in the direction of due East ( at the equator ) but there is plenty to do afterwards.

This reminds me a space picture book I had when I was about six years old ( so that's 1966 folks ). It had alot of gee-whiz rubbish in it that I swallowed whole at the time. I clearly remember it stating that the space between the planets was filled with poisonous air, so you can gauge the editing quality by that. Anyways - and this is the point of my diversion - if that was truly so then you could have used the resistance of that air to retard your forward flight, lose energy and then still drift into the Sun. I was left with the impression that spacesuits were sealed mainly to prevent the poison air getting in. A reasonable hypothesis, I might add, from data obtained. When Apollo came along I had to get used to the idea that spacecraft could be different shapes. I was a quiet-in-the-corner dreamer type*.

SpaceX is certainly ramping up their schedule nicely. While we would like a low orbit delivery to see a 1st stage recovery enacted, they do need to collect real money to return on investment.

Cheers, Mike.

* [up on lectern]
Our current Child Labeling & Medicating Industry would probably have nailed me as Autism Spectrum Disorder, Dyslexic, Stupid, or Oppositional Defiant Disorder ( if I said no ) : all presently ridiculously broad categories that have shifted & separated the goal posts from the ends of the field to be placed at the wings. Thus any kick along the long axis of the field will achieve a goal. So no tested child will escape an implicitly negative label, requiring of course further inspections, testing, typically pharmacological intervention, and now low self-esteem because they obviously have a problem, right ? There is a small fraction of children who actually need this. The vast majority don't. It is a modern day tragedy that worldwide so many children have suffered subverted childhoods because the professional adults that care for them can't cope with natural variance .... bizarre.
[step down from lectern]

I have made this letter longer than usual because I lack the time to make it shorter. Blaise Pascal

mikey
mikey
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RE: So what I did was get

Quote:

So what I did was get this shot :

and turn it into a 2000 piece jigsaw, 68 cm x 96 cm, for my son's birthday. There's a number of mobs that will do this for you, I chose puzzlesprint.com and had it delivered ( from Latvia via DHL ) for ~ $120 AUD all up.

That's cool!

Quote:
Peter is right. To fall into the Sun you have to clip a 30 km/sec tangential 'gift' that you get automatically by launching off Earth. You can knock 1 km/sec off that by launching at midday in the direction of due East ( at the equator ) but there is plenty to do afterwards.

That's case closed on that idea then!

Quote:
This reminds me a space picture book I had when I was about six years old ( so that's 1966 folks ). It had alot of gee-whiz rubbish in it that I swallowed whole at the time. I clearly remember it stating that the space between the planets was filled with poisonous air, so you can gauge the editing quality by that. Anyways - and this is the point of my diversion - if that was truly so then you could have used the resistance of that air to retard your forward flight, lose energy and then still drift into the Sun. I was left with the impression that spacesuits were sealed mainly to prevent the poison air getting in. A reasonable hypothesis, I might add, from data obtained. When Apollo came along I had to get used to the idea that spacecraft could be different shapes. I was a quiet-in-the-corner dreamer type*.

This is similar to the training I had to do as a 6 year old, in 1958, of hiding under our desks to prevent being killed by a nuclear bomb exploding near our Air Force Base. I'm glad we have advanced our teachings since then!!

Quote:


Cheers, Mike.

* [up on lectern]
Our current Child Labeling & Medicating Industry would probably have nailed me as Autism Spectrum Disorder, Dyslexic, Stupid, or Oppositional Defiant Disorder ( if I said no ) : all presently ridiculously broad categories that have shifted & separated the goal posts from the ends of the field to be placed at the wings. Thus any kick along the long axis of the field will achieve a goal. So no tested child will escape an implicitly negative label, requiring of course further inspections, testing, typically pharmacological intervention, and now low self-esteem because they obviously have a problem, right ? There is a small fraction of children who actually need this. The vast majority don't. It is a modern day tragedy that worldwide so many children have suffered subverted childhoods because the professional adults that care for them can't cope with natural variance .... bizarre.
[step down from lectern]

I'm not sure alot of this wasn't an attempt to say 'my child isn't normal and that's why they aren't as good as all the other kids' by parents who didn't really understand that each kid is different. Remember there were few books, before Dr. Spock, on how to raise a kid, and they do NOT come with instruction books, as I told mine more than once when I made bad decisions. Having 'something wrong' with their kid gives the parents an excuse for why their kid isn't doing as well as everyone else. I think the kids just took the easy way out and said 'see I can't do it and YOU said so by giving me all these pills'.

David S
David S
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RE: RE: This reminds me a

Quote:
Quote:
This reminds me a space picture book I had when I was about six years old ( so that's 1966 folks ).


I was a wee bitty infant for the last four weeks of 1966. (Okay, not that wee bitty, I was 9 lbs. 3 oz. at birth.)

Quote:
Quote:
It had alot of gee-whiz rubbish in it that I swallowed whole at the time. I clearly remember it stating that the space between the planets was filled with poisonous air, so you can gauge the editing quality by that. Anyways - and this is the point of my diversion - if that was truly so then you could have used the resistance of that air to retard your forward flight, lose energy and then still drift into the Sun. I was left with the impression that spacesuits were sealed mainly to prevent the poison air getting in. A reasonable hypothesis, I might add, from data obtained. When Apollo came along I had to get used to the idea that spacecraft could be different shapes. I was a quiet-in-the-corner dreamer type*.

This is similar to the training I had to do as a 6 year old, in 1958, of hiding under our desks to prevent being killed by a nuclear bomb exploding near our Air Force Base. I'm glad we have advanced our teachings since then!!


https://youtu.be/IKqXu-5jw60

David

Miserable old git
Patiently waiting for the asteroid with my name on it.

mikey
mikey
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RE: RE: This reminds me a

Quote:
Quote:
This reminds me a space picture book I had when I was about six years old ( so that's 1966 folks ).

I was a wee bitty infant for the last four weeks of 1966. (Okay, not that wee bitty, I was 9 lbs. 3 oz. at birth.)

I am surrounded by "kids"!!

Yup exactly!!

robl
robl
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NASA tests its largest rocket

NASA tests its largest rocket engine to date. See it here

archae86
archae86
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RE: NASA tests its largest

Quote:
NASA tests its largest rocket engine to date.


That one is a big solid. Basically a space shuttle SRB with one additional segment.

TimeLord04
TimeLord04
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RE: RE: RE: This

Quote:
Quote:
Quote:
This reminds me a space picture book I had when I was about six years old ( so that's 1966 folks ).

I was a wee bitty infant for the last four weeks of 1966. (Okay, not that wee bitty, I was 9 lbs. 3 oz. at birth.)

I am surrounded by "kids"!!

Yup exactly!!


I was only two when Neil and Buzz landed on the moon. (Well, two years and 20 days...) :-O ;-)

TimeLord04
Have TARDIS, will travel...
Come along K-9!
Join SETI Refugees

robl
robl
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RE: RE: NASA tests its

Quote:
Quote:
NASA tests its largest rocket engine to date.

That one is a big solid. Basically a space shuttle SRB with one additional segment.

Yes, but how would you like your steak?

David S
David S
Joined: 6 Dec 05
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RE: RE: RE: RE: This

Quote:
Quote:
Quote:
Quote:
This reminds me a space picture book I had when I was about six years old ( so that's 1966 folks ).

I was a wee bitty infant for the last four weeks of 1966. (Okay, not that wee bitty, I was 9 lbs. 3 oz. at birth.)

I am surrounded by "kids"!!

Yup exactly!!


I was only two when Neil and Buzz landed on the moon. (Well, two years and 20 days...) :-O ;-)


So I've got you beat by about 7 months.

David

Miserable old git
Patiently waiting for the asteroid with my name on it.

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