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APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 5:12 am
by APOD Robot
Falcon 9 First Stage Landing
Explanation: The booster has landed
. Spaceflight took a
step toward the less expensive last week when the first stage of a
Falcon 9 rocket set down on a landing pad not far from its
Florida launch. Previously, most rocket stages remained unrecovered -- with the significant exception of the
Space Shuttles landing on a runway and their
solid rocket boosters being
fished back from the sea. The landing occurred while the
Falcon 9 second stage continued up to launch several
communications satellites into low Earth orbit. The controlled landing, produced by
SpaceX, was the first of its kind, but followed a
booster landing last month by
Blue Origin that did not involve launching satellites.
Boeing and
SpaceX were
selected last year by
NASA to launch
future astronauts to the
International Space Station. The
pictured rocket booster will be analyzed for
wear and reusability, but then is
scheduled to be
retired.
[/b]
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 5:39 am
by Guest
I'm likely to be a lot older than most posting here. I've heard many claims to cheaper cost to orbit. Those landing legs weigh a lot. That means that the payload to orbit was lowered. Every pound in orbit still costs more than gold. We need to transition to nuclear rockets.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 9:25 am
by Boomer12k
WOW....just like a "B" Sci-fi movie....land on the tail....So...COOL!!!!
It is a mini-ship in itself...
:---[===] *
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 9:28 am
by Boomer12k
Guest wrote:I'm likely to be a lot older than most posting here. I've heard many claims to cheaper cost to orbit. Those landing legs weigh a lot. That means that the payload to orbit was lowered. Every pound in orbit still costs more than gold. We need to transition to nuclear rockets.
Not only that...it had to have its own FUEL for the landing.
But they did launch 11 satellites....though smaller ones...
:---[===] *
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 12:29 pm
by RedFishBlueFish
But, that is how ALL spaceships landed when I was a lad.
Remarkable! Even if it does not have the iconic fins of a real spaceship.
![Image](http://roymathur.com/blog/wp-content/uploads/2012/08/destination-moon-silver-rocket.jpg)
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 1:30 pm
by heehaw
Guest wrote:I'm likely to be a lot older than most posting here. I've heard many claims to cheaper cost to orbit. Those landing legs weigh a lot. That means that the payload to orbit was lowered. Every pound in orbit still costs more than gold. We need to transition to nuclear rockets.
Correct. There is no free launch.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 2:31 pm
by Steve Dutch
This is one of the concepts depicted years ago in science fiction. Like a reusable lander. And just like the Space Shuttle, I suspect it will be a concept that looks cool on paper but impractical in reality. Remember how the Space Shuttle was going to launch every two weeks? The Space Shuttle was very inspiring (I saw the last launch) but just didn't deliver on its promises. I suspect launchers that land vertically will be the same.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 3:30 pm
by neufer
Guest wrote:
Every pound in orbit still costs more than gold.
Code: Select all
Gold's current value ~ $15,000 per pound
SpaceX's current orbit price ~ $2,500 per pound
Projected orbit prices with reusable rockets ~ $500 per pound
Silver's current value ~ $250 per pound
https://en.wikipedia.org/wiki/Space_launch_market_competition wrote:
<<In early December 2013, SpaceX flew its first launch to a geosynchronous orbit providing additional credibility to its low prices which had been published since at least 2009. The low launch prices offered by SpaceX (less than $2,500 per pound to orbit for Falcon 9 v1.1 and $1,000 for Falcon Heavy), especially for communication satellites flying to geostationary (GTO) orbit, resulted in market pressure on its competitors to lower their own prices.>>
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 3:37 pm
by Chris Peterson
Steve Dutch wrote:This is one of the concepts depicted years ago in science fiction. Like a reusable lander. And just like the Space Shuttle, I suspect it will be a concept that looks cool on paper but impractical in reality. Remember how the Space Shuttle was going to launch every two weeks? The Space Shuttle was very inspiring (I saw the last launch) but just didn't deliver on its promises. I suspect launchers that land vertically will be the same.
I'm inclined to agree. We're not going to see anything but chemical rockets for a very long time yet (for launches from Earth... there are certainly better options on the horizon for operation in space). And systems with significant reusability are likely to be economically poor choices. The Russians probably have it right- cheap launches with mostly disposable rockets.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 6:39 pm
by neufer
Chris Peterson wrote:
systems with significant reusability are likely to be economically poor choices.
Vulnerable systems that put humans at risk (e.g., the Space Shuttle) are likely to be economically poor choices.
Unmanned systems with some re-usability are likely to be economically good choices.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 6:43 pm
by Chris Peterson
neufer wrote:Unmanned systems with some re-usability are likely to be economically good choices.
I agree.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 6:53 pm
by Ron-Astro Pharmacist
Maybe I've been reading too much sci-fi but
other than rocket launch options always seemed like a good alternative. Are we even close to such technology?
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 7:09 pm
by Chris Peterson
Ron-Astro Pharmacist wrote:Maybe I've been reading too much sci-fi but
other than rocket launch options always seemed like a good alternative. Are we even close to such technology?
Probably not (except for the space plane approach, which is currently feasible). Most of these methods require extremely high initial investments, and that's not going to happen until space is much more commercialized than it currently is.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 7:41 pm
by neufer
Chris Peterson wrote:Ron-Astro Pharmacist wrote:
Maybe I've been reading too much sci-fi but
other than rocket launch options always seemed like a good alternative. Are we even close to such technology?
Probably not (except for the space plane approach, which is currently feasible). Most of these methods require extremely high initial investments, and that's not going to happen until space is much more commercialized than it currently is.
Reusable spaceplane/boosters may well become the norm:
https://en.wikipedia.org/wiki/XS-1_%28spacecraft%29 wrote:
<<The DARPA XS-1 will be a reusable spaceplane/booster to deliver small satellites into orbit for the U.S. Military. The XS-1 is to directly replace the "first stage" of a multistage rocket that will be capable of flying at hypersonic speed at suborbital altitude, enabling one or more expendable upper stages to separate and deploy a payload into low Earth orbit. The XS-1 would then return to Earth, where it could be serviced fast enough to repeat the process at least once every 24 hours. The goals of the program as of September 2013 were: The space plane must carry a 3,000–5,000 lb payload to low Earth orbit for less than a cost of US$5 million per flight, at a rate of 10 or more flights per year; currently, launching that type of payload requires using an Orbital Sciences Corporation Minotaur IV expendable booster, priced at $55 million once per year.>>
https://en.wikipedia.org/wiki/LauncherOne wrote:
<<LauncherOne is an orbital two-stage air-launched vehicle under development by Virgin Galactic in the 2010s. It is an air launch to orbit rocket, designed to launch "smallsat" payloads of 440 lb into Sun-synchronous orbit, following air launch from a carrier aircraft at high altitude. Launches are projected to begin in 2017.>>
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 8:09 pm
by heehaw
Here's my published letter to TIME magazine, 1981 May 11, page 5: "I am an astronomer, and I was filled with the glee of a child when I saw the space shuttle return safely. We have entered a new age! Future flights are estimated to cost $30 million each---that is, 15 cents from each of us. A bargain to build a strong American presence in space!" Thirty-four years later, here we are! Someone tell me where we will be 34 years from today.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 8:19 pm
by Chris Peterson
heehaw wrote:Here's my published letter to TIME magazine, 1981 May 11, page 5: "I am an astronomer, and I was filled with the glee of a child when I saw the space shuttle return safely. We have entered a new age! Future flights are estimated to cost $30 million each---that is, 15 cents from each of us. A bargain to build a strong American presence in space!" Thirty-four years later, here we are! Someone tell me where we will be 34 years from today.
The space shuttle was not something arrived at because of real need, but rather, a political toy.
I expect that in 34 years we'll still be throwing away money because of poor political decisions that have nothing to do with our actual capabilities or requirements.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 8:23 pm
by BMAONE23
Chris Peterson wrote:Ron-Astro Pharmacist wrote:Maybe I've been reading too much sci-fi but
other than rocket launch options always seemed like a good alternative. Are we even close to such technology?
Probably not (except for the space plane approach, which is currently feasible). Most of these methods require extremely high initial investments, and that's not going to happen until space is much more commercialized than it currently is.
Probably a better option would be to build a similar Mag Lev/Mag Repulsion drive underground for a straight stretch of about 6 miles then angle the bore up inside of a mountain (like Kilimanjaro 19,000' or Mt Kenya 17,000') on the equator to exit at the top where the atmosphere is already thinner. The launch tube could be depressurized prior to launch to equate to the ambient pressure at the top of the mountain.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 8:31 pm
by BMAONE23
heehaw wrote:Here's my published letter to TIME magazine, 1981 May 11, page 5: "I am an astronomer, and I was filled with the glee of a child when I saw the space shuttle return safely. We have entered a new age! Future flights are estimated to cost $30 million each---that is, 15 cents from each of us. A bargain to build a strong American presence in space!" Thirty-four years later, here we are! Someone tell me where we will be 34 years from today.
Running feasibility studies for the practical application of capturing an asteroid, relocating it into a geostationary but low orbit (600K) and building a tether to it from the ground for a space elevator. Perhaps already having made several disastrous attempts at nudging various small asteroids causing unanticipated side effects in the gravitational status quo of our local neighborhood
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 8:45 pm
by Chris Peterson
BMAONE23 wrote:Chris Peterson wrote:Ron-Astro Pharmacist wrote:Maybe I've been reading too much sci-fi but
other than rocket launch options always seemed like a good alternative. Are we even close to such technology?
Probably not (except for the space plane approach, which is currently feasible). Most of these methods require extremely high initial investments, and that's not going to happen until space is much more commercialized than it currently is.
Probably a better option would be to build a similar Mag Lev/Mag Repulsion drive underground for a straight stretch of about 6 miles then angle the bore up inside of a mountain (like Kilimanjaro 19,000' or Mt Kenya 17,000') on the equator to exit at the top where the atmosphere is already thinner. The launch tube could be depressurized prior to launch to equate to the ambient pressure at the top of the mountain.
Now you just need to find an extra trillion or so dollars for the project...
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 8:47 pm
by Chris Peterson
BMAONE23 wrote:heehaw wrote:Here's my published letter to TIME magazine, 1981 May 11, page 5: "I am an astronomer, and I was filled with the glee of a child when I saw the space shuttle return safely. We have entered a new age! Future flights are estimated to cost $30 million each---that is, 15 cents from each of us. A bargain to build a strong American presence in space!" Thirty-four years later, here we are! Someone tell me where we will be 34 years from today.
Running feasibility studies for the practical application of capturing an asteroid, relocating it into a geostationary but low orbit (600K) and building a tether to it from the ground for a space elevator. Perhaps already having made several disastrous attempts at nudging various small asteroids causing unanticipated side effects in the gravitational status quo of our local neighborhood
We don't even have the physical capability to do this now. Some serious advances in material science will have to occur first.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 9:01 pm
by FLPhotoCatcher
Here is my idea (if Blue Origin or SpaceX would send me a 1% royalty, I would be happy).
Eliminate the landing legs, and land it on a computer-controlled movable metal grate. The computer would move the grate to balance the rocket like a person balances a vertical pole. Then computer-controlled arms would move-in near the top of the rocket and grab on to it to secure it.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Mon Dec 28, 2015 9:26 pm
by Chris Peterson
FLPhotoCatcher wrote:Here is my idea (if Blue Origin or SpaceX would send me a 1% royalty, I would be happy).
Eliminate the landing legs, and land it on a computer-controlled movable metal grate. The computer would move the grate to balance the rocket like a person balances a vertical pole. Then computer-controlled arms would move-in near the top of the rocket and grab on to it to secure it.
I built a pencil balancer like that about 30 years ago...
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Tue Dec 29, 2015 8:10 pm
by DavidLeodis
I'm not very good at understanding the physics of launchings/landings so please don't accuse me of being stupid as I don't understand why the engines are apparently being fired for a landing, as surely that would result in lifting! I'm sure it's not but it does look as if the video could be being shown in reverse!
![Rocketship :rocketship:](./images/smilies/rocketship.gif)
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Tue Dec 29, 2015 8:23 pm
by Chris Peterson
DavidLeodis wrote:I'm not very good at understanding the physics of launchings/landings so please don't accuse me of being stupid as I don't understand why the engines are apparently being fired for a landing, as surely that would result in lifting! I'm sure it's not but it does look as if the video could be being shown in reverse! :? :rocketship:
"Lift" doesn't necessarily mean "rising". It just means a force that operates opposite that of gravity. With no engines, the rocket would fall very fast into the ground and be destroyed. With too much thrust, it would rise. A controlled landing requires providing just enough thrust to almost- but not quite- offset gravity, allowing the rocket to settle gently to the ground.
Airplanes do the same thing, always generating lift with their wings, but controlling it such that the plane rises, stays level, or descends.
Re: APOD: Falcon 9 First Stage Landing (2015 Dec 28)
Posted: Tue Dec 29, 2015 8:36 pm
by neufer
Chris Peterson wrote:DavidLeodis wrote:
I'm not very good at understanding the physics of launchings/landings so please don't accuse me of being stupid as I don't understand why the engines are apparently being fired for a landing, as surely that would result in lifting! I'm sure it's not but it does look as if the video could be being shown in reverse!
![Rocketship :rocketship:](./images/smilies/rocketship.gif)
A controlled landing requires providing just enough thrust to
almost- but not quite- offset gravity, allowing the rocket to settle gently to the ground.
I
almost made the same mistake as Chris... but I caught myself (this time):
A controlled landing requires providing just enough thrust to
almost- but not quite-
offset gravity (
and then some), allowing the rocket to settle gently to the ground.
The engines are firing so as to
slightly exceed gravity in order to transition from:
- 1) a downward moving rocket at the top
2) to a stationary rocket at the bottom
3) with gases exiting the rocket.
Note: If the rocket hadn't been shut down it simply would have taken off.
- ------------------------------------------------------
This video could also be shown in reverse:
------------------------------------------------------
The engines are firing so as to slightly exceed gravity in order to transition from:
- 1) a stationary rocket at the bottom
2) to an upward moving rocket at the top
3) with gases entering the rocket.
This corresponds exactly to a (slow motion) rocket launch
except for the gases.