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>that shit cost a lot of money to develop, which most countries don't have especially nowadays with the current crisis.

The entire development of Falcon9 including getting the boosters to land has cost far less than $2B.

The development cost of Ariane6 (completely disposable) has cost almost $4B so far with more costs to come.

So the idea that the money is not available is completely wrong.

"Playing" is the word here.

When in 2015-2017 SpaceX succeeded in landing their Falcon9 ArianeSpace and ESA acknowledged that this rocket would endanger the market position of their Ariane5. So they started to develop Ariane6.

But with the expressed goal of not designing it in a way reusability could be implemented later on, if need arose.

And they designed it as a rival to the Falcon9 of 2017, a rocket vastly less capable compared to the Falcon9 of today.

ArianeSpace and ESA now struggle to fill the books.

Soooo do they do the responsible thing and design a new rocket (ArianeNext) that will match SpaceX's capabilities in the future when ArianeNext will come online?

Ha, no. They have set up ArianeNext as a competitor to the Falcon9 of today, while betting that SpaceX can't get Starship to fly.

They are "playing" and they are playing badly.

Yes, but launching a nuke on top of a satellite would be way more complex and expensive, plus you'd be violating a few treaties.

Not to mention you dont want to screw around the kind of asteroid that wouldnt just get obliterated by the nuke. The point was analyzing how much of an effect a kinetic impactor would have on an asteroid.

It's a matter of time, mostly. The big issue is that you have to design for it up front. Which doesn't necessarily mean you have to commit to it with the first launch, although that might be changing as SpaceX redefines what is market competitive. But you have to design the vehicle so that landings are feasible and sensible.

Most of the traditional optimizations for expendable launches de-optimize for reuse. The first stage is where there's the least sensitivity to mass, so first stages end up being the cheapest parts of the rocket with the upper stages being the most costly. They also tend to be optimized to have a small number of engines. The Atlas V has one engine on the first stage, for example. These things make reuse harder (can't throttle deep enough to make landing easy) and less worthwhile (you're reusing the cheapest part).

RocketLab and Blue Origin are designing their next gen rockets with reuse in mind, hopefully they can achieve success and get some market diversification in the reusable rockets field.

Delta Clipper was working but NASA killed it because of their fetish for space-planes.

Falcon 9 second stage isn’t reusable, though there were some early plans to do so. The problem is that the second stage travels to orbit, so it’s an order of magnitude faster and therefore will hit the atmosphere an order of magnitude harder.

So now second stages are typically burnt up in the atmosphere, or stay in orbit depending on launch trajectories.

Dragon is reused, the veteran Endeavour has flown four crews.

Interesting. My PhD certificate (UK) says Doctor of Philosophy yet my title is PhD

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Hello u/ytness2, your submission "Does the solar system have an elliptical orbit around SagA*? If so, how do we know this?" has been removed from r/space because:

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Falcon 9 “made its first successful landing back on Earth” with “SpaceX’s 20th launch” of the rocket:

>A little more than seven years have passed since the Falcon 9 rocket made its first successful landing back on Earth. That was just SpaceX's 20th launch of the Falcon 9 rocket.

I've been out of the loop. Are the second stage rocket (if there is one) or the Dragon reusable? If not, are they planning to make second stage and Dragon reusable?

Also, if second stage isn't reusable, what happens to it?

>Monday morning's launch was the 207th overall flight of the rocket.

>That was just SpaceX's 20th launch of the Falcon 9 rocket.

Is this a typo or am I missing something, I see a clear contradiction but perhaps the article is just poorly written? Could this mean that totally they've launched all Falcon versions 207 times; 20 times with Falcon 9 and 207-20=187 with Falcon 1?

There's a few UK institutions that call it a DPhil instead of PhD (including where I went), and I don't know why. Knowing Oxford, I wouldn't discount the possibility that someone was making a point about latin word order or being different for the sake of being different.

Quite a few things, really. I had a lot of options, but I currently work as a data engineer/scientist.

I wish biological and environmental sciences would follow the same process. Also making reviewer comments public, it can be such a toxic and murky process to publish.

The Orbcomm-2 webcast still gives me goosebumps. And I strongly believe the image from the Falcon Heavy test flight, of those twin boosters landing together, will come to be immortalised and remembered as the moment in which reusability became a fixture of the general public's perception of spaceflight and rocketry.

Theoretically, you are right. We haven't proven that we aren't currently flying off into space right now, but based off of what we can observe and know, it's very likely that we are orbiting our galaxy (not necessarily SagA, but, rather, a sort of galactic barycenter). It's not a fact in the scientific/mathematical sense of the word, but the probability of any other explanation is so low that we can treat it as such and form our assumptions around it. That's how most high-level science and mathematics work though. Many things that we treat as facts or proofs are actually just theories and very educated guesses, but they work very well for us and help us innovate and learn about the world around us; sometimes we don't have to prove something for it to be useful to us.

Wait, are you suggesting that what would amount to a trillion dollar industry capable of getting multiple asteroids into orbit around the moon, will be accomplished by a terrorist organization?

I'm done talking to you. You are just being ridiculous now.

Musk is still the boss, he sets the agenda for everyone under him. To disregard that is silly regardless of what you think of him.

You didn't prove anything. So there's that. You just want to lie and you offered no proof for your position that the governments of the world don't automatically seek to weaponize any new technology.

There's actually plenty of evidence on your side at least in the short term, but you chose to shit on my rock solid proof that nuclear energy production also wasn't proposed to the public as a weapon first. You chose to ignore actual fact, produce no evidence all the while I took every one of your examples and proved you don't know what you're talking about, or specifically lying.

I don't know which one it is, nor does it matter because either way you clearly enjoy funding war.

I'm done with you.

Good afternoon.

Is there any personal/keepsake item you'd like to take to the moon?