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SpaceX Successfully Launches, Recovers Falcon 9 For CRS-12 (techcrunch.com)
Another SpaceX rocket has been successfully launched from NASA's Kennedy Space Center today, carrying a Dragon capsule loaded with over 6,400 pounds of cargo destined for the International Space Station. This marks an even dozen for ISS resupply missions launched by SpaceX under contract to NASA. TechCrunch reports: The rocket successfully launched from NASA's Kennedy Space Center at 12:31 PM EDT, and Dragon deployed from the second stage as planned. Dragon will rendezvous with the ISS on August 16 for capture by the station's Canadarm 2 robotic appendage, after which it'll be attached to the rocket. After roughly a month, it'll return to Earth after leaving the ISS with around 3,000 pounds of returned cargo on board, and splash down in the Pacific Ocean for recovery. There's another reason this launch was significant, aside from its experimental payload (which included a supercomputer designed to help humans travel to Mars): SpaceX will only use re-used Dragon capsules for all future CRS missions, the company has announced, meaning this is the last time a brand new Dragon will be used to resupply the ISS, if all goes to plan. Today's launch also included an attempt to recover the Falcon 9 first stage for re-use at SpaceX's land-based LZ-1 landing pad. The Falcon 9 first stage returned to Earth as planned, and touched down at Cape Canaveral roughly 9 minutes after launch.
Which is what I always had hoped for the shuttle program
Is there anything that guy CAN'T do?
Kilograms are mass; pounds are weight
Because it's American. Europeans coming to a foreign site insulting the local culture is immature and rude. Why do all of you feel the need to do this? We don't visit your websites and insult you for continuing to pronounce Aluminum wrong. Please kindly go invent your own reusable rocket system and then you can feel free to measure its payload capacity with whatever units you prefer.
Because it's press releases for the unwashed masses. NASA, and the ISS in particular, operate entirely in a pure metric environment. Heck, this is the same for the other and related agencies. You walk into JPL and ask where the washroom is, you're likely to hear something along the lines of 5 meters down the hall, and to your left.
...si hoc legere nimium eruditionis habes...
First the obvious, the Dragon will be berthed to the station, not to the rocket. That was done in Florida prior to launch.
Secondly, this is likely the last new Dragon 1 pressure vessel that will be launched. Given that they splash down in rather corrosive salt water, there's significant effort to re-manufacture the capsules for launch, and the pressure vessel is a portion of that.
...si hoc legere nimium eruditionis habes...
The original source first mentions kilograms
CRS-12 will deliver 2,910 kilograms (6,415 pounds) of cargo to the station
https://www.nasaspaceflight.co...
Pretty sure NASA is American...
Because the journalists at techcrunch.com don't know what a kilogram is.
Thankfully NASA does. https://www.nasaspaceflight.co...
IIRC (it has been a long time since I studied physics), mass was measured in Newton's. The definition of weight as distinct from mass is that all matter has mass all the time, but it only has weight when that mass is experiencing the force of gravity within a gravitational field.
the Kilogram is a measure of mass. However, due to the way that scales and the like are calibrated here on earth, it corresponds to the weight as well. Force is measured in Newtons (F=ma), so if you hold a 1kg object suspended in the air, you need to apply 9.8 newtons of force to prevent it from moving.
...si hoc legere nimium eruditionis habes...
Kilograms are mass; pounds are weight
Pounds can be considered as either mass or weight.
Weight is measured in units of force. By convention, one pound of force is the force created on one pound of mass at Earth's sea level (or something like that.)
On the other hand, kilograms are strictly a measure of mass. However, scales (such as those in a butcher shop or in your bathroom) usually measure the force of gravity on an object (i.e, its weight) but display the equivalent mass (in kilograms or pounds.)
No, but if you land a jet on an aircraft carrier, that's generally referred to as aircraft recovery.
...si hoc legere nimium eruditionis habes...
When you talk about "space things" you don't use pounds, you use the metric system. http://edition.cnn.com/TECH/space/9909/30/mars.metric.02/
Nah. Pounds measures currency.
There's a joke about that.
"There are two kinds of countries: the kind who have sent men to the moon, and the kind who use the metric system."
I got to take a private tour of the SpaceX testing facility in Texas a few weeks back, I was a few feet away from the team installing the flight computers on top of the Stage 1 in the hanger in McGregor a few weeks back.
Amazing stuff to see in person, and really emotional to see the same Stage 1 launch today and land.
(On another note, the people in the hangar were listening to Katy Perry as they were working. Sorry guys, I had to.)
Scientists, especially rocket scientists, need to distinguish between mass and weight (force). In SI, it is very clear: mass is in kilograms, weight is in Newtons. Pounds can be mass or weight, depending on what system you use.
In Imperial, traditional use treats mass and weight as interchangeable, both measured in pounds. Scientific use must make a distinction, hence must choose whether a pound is mass or force. If you choose to treat a pound as mass, then the unit of force in your system is the poundal. If you choose to tread a pound as force, then your unit of mass is the slug. Both systems have been used, but I have little idea as to their current prevalence as I am both a scientist and living in a non-backwards country, so I only know these systems like I know farthings, shillings, crowns and guineas. (There is/has been yet a third option, using pounds-mass and pounds-force. This would require various formulae to have factors of 32 (feet/sec/sec) in them to make them work.)
More details at Wikipedia.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
This post demonstrates that any sufficiently advanced idiocy or ignorance is indistinguishable from trolling.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
No, youâ(TM)re flat out wrong. The kg is the SI standard unit of weight. The N is the SI standard unit of mass and corresponds to 1kg of weight in 1 gravity.
You have it flat out backwards.
Pounds can be considered as either mass or weight.
The imperial unit of mass is the slug.
Kilogrammes are what the world uses to measure weight (and mass).
Pounds are what the US, Liberia and Myanmar use.
Named after his massiveness Jabba the Hut?
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You do know that since the Mendenhall Order of 1893, US customary units such as feet and pounds are actually defined in terms of metric ?
Kilograms are mass; pounds are weight
This and quite a few comments below are wrong. Both kilograms and pounds measure mass. Weight is another name for force, which is measured in different units in both systems. There are force units which have similar names to their mass counter-parts (e.g., kilogram-force or pound-force). Conventionally, we talk about kilograms/pounds and mass/weight almost interchangeably, but this is technically wrong.
COMPLETELY-MOTIVATED SELF-ADVERTISEMENT: I have developed completely from scratch a quite comprehensive unit-parsing library in C# (converted to Java): UnitParser (first part of FlexibleParser). It is open source and the files dealing with basic unit classifications are quite user-friendly. For example, unit names in C# and Java.
Custom Solvers 2.0 = Alvaro Carballo Garcia = varocarbas.
Rather than "Weight is another name for force", I should have written "weight is a force (mass * gravity acceleration)".
Custom Solvers 2.0 = Alvaro Carballo Garcia = varocarbas.
There's a joke about that.
"There are two kinds of countries: the kind who have sent men to the moon, and the kind who use the metric system."
The actual joke is that NASA, the company that landed the men on the moon, now mostly uses the metric system, and was partly using it back then.
In fact, the guidance computers of the Apollo missions were programmed in metric, but displayed/input in English.
There's a joke about that.
"There are two kinds of countries: the kind who have sent men to the moon, and the kind who use the metric system."
The actual joke is that NASA, the company that landed the men on the moon, now mostly uses the metric system, and was partly using it back then. In fact, the guidance computers of the Apollo missions were programmed in metric, but displayed/input in English.
IIRC, the USA was the second nation to switch to the metric system. However, it does not forcefully proscribe its usage. For science, metric notation is used for most everything. Even in standard measurements, they are all officially determined by metric values.