marsokod

You need to push them in a correct and somewhat precise way so you need to grab the debris somehow before applying the push.

As of 2018, the US GDP is 7.34x the one of France, not 10x. And in 2019, the US population is 4.91x bigger that France population, leading to a GDP per capita being 1.50x higher, not 2x.

You cannot round numbers at 1 significant digit and use them for further computations, that's butchering math.

You would still need a delta-V to agglomerate multiple debris. Depending on the context, it may be cheaper to just de-orbit them.

We're a long way from recycling stuff in orbit. We've not even started manufacturing anything worthy in orbit.

This harpoon is designed to catch big debris. The target used for this demonstration is a honeycomb panel typical of bigger satellites.

That's what is being assessed with this mission. If creating a few debris with he harpoon allows you to de-orbit the whole debris, which would have generated a certain amount of small debris over time, then it can be a win if the former is smaller than the potential latter.

Also, depending on the orbit considered, the debris generated by the harpoon may be less harmful: they have typically a high surface area/weight ratio so they will deorbit fast if the altitude is low enough, like for this mission.

I can see plenty of issues for the users if they just change http to https.

All the installs in a professional network where the use of a proxy changes the certificate would have trouble updating. So now it is changing changing http to https and be able to recover the company certificates in some way, in many different environments.

So yeah, the change is not trivial and will likely break the setup of millions of users. Downloading over http with a proper signature mechanism can be safe and is much easier for the users. If people have concerns over the way VLC is doing it, they are free to show how this can be broken and offer a fix.

It does not affect the ESA membership, and does not prevent UK companies to launch from French Guyana. However, shipping may become a bit more complex and costly, and procurement will be thougher, especially in the first months.

It is even simpler than that: you've got a computer for the platform, and another one for the payload. You send commands to the platform computer over the TT&C frequency at a few kbps.

You can also update the platform OBC as well, with its bootloader then selecting which SW image to use.

That is not what he said though. He said there would be demand for gas well into the 2040s, and since most (all?) these bans only concern new sales, it will take ~20 years after the bans to get rid of a majority of the ICEs.

The oil industry already knows they will be done in the 40s. Their EUR (well estimated already 50 years ago) shows that growth will be extremely difficult past the 30s. They won't fight a ban on new sales except for the few who cannot diversify in other domains.

USB-C has been designed so that the male part is less resistant than the female part. This way, the connector on the device will see less stress and should last longer.

Obviously they won't be last indefinitely, especially for a connector used as much as a power input. And I have no idea if all the connectors follow properly the standard regarding materials.

But given the built quality of Apple cables, I doubt we will see the device connector wear before the cable is ripped apart by natural degradation, after 1 or 2 years.

You can use a lot of missiles to destroy any spacecraft easily, while creating a big mess. But this is not really true for the deorbiting part: satellites are not planned for high velocity impact. So either you have a low velocity impact but you delta-v is not high enough to change significantly the orbit of the debris, or you go full speed into it, and explode everything into thousands of small debris, with very random orbit.

The net is just a technique to catch a debris. After it is caught, you have many different ways of deorbiting: either the net has a solar sail and deploy it, or it has a small propulsion system and uses it, or if you hook the net to your de-orbiter, you can use the tether as a sling to release the debris in a shorter life orbit while your de-orbiter is raised to another orbit where it can find its next debris (the most promising system, but the sling part will be quite difficult to master)

EU membership played a key role in this project though. The consortium would not have had the same funding from the European Commission if the UK was outside EU.

In the early plans the harpoon was launched at a moving target. But in addition to the complexity and the risk associated with that, this prevented having a close-up look at the target after the operation. A harpoon for debris removal is only useful if it does not create too many debris and you cannot really assess how many were generated if the harpoon and it's target are floating away.

I concur with you in the drag sail. So many LEO projects are planning on using propulsion for deorbiting, which requires having a fairly working spacecraft. Drag sails or other deployables do not require a lot of power, are completely passive once deployed, and make the object even more trackable.

I thought that the ISP were providing that service as part of the package. Given they do a lot of IP traffic alteration (acknowledging TCP packets at the gateway level instead of letting the client doing it), this is not much.

Yes, and to add to that a vast majority of this 11% is grown at quite a distance from the continent:

Of the total banana volume marketed in Europe, which amounted to 6,122,898 tonnes, 11.3% is of EU origin, with the Canary Islands accounting for more than 60%, followed by the French Martinique and Guadeloupe (36%) and by the Portuguese Madeira (3%).

Water is the space fuel of the future. Well, at least the space oil of the future - if you start mining asteroid and comets, water is one of the best component you can get: good for any life around, quite a good solvent if you need one, and more importantly can be a fuel like this or be transformed into oxygen and hydrogen, which is rocket fuel as well.

Also, good luck depleting the water on Earth with space travel. There would be other issues way before this happens.

Windows does not seem to be aimed at power users anymore, unless they are in a big company environment. You can manage which updates are sent, and when, if you have a Windows server distributing the updates. But that is overkill for small companies.

The worst part is that there is a setting for it (at least on the pro version). However, even with it selected I see an automatic reboot every three or four months. And that is by applying updates when I happen to work on it.

And there is nothing to disable the shortcuts or installation of silly program like candy crush.

I remember reading something about a Windows 10 edition without all this crap, but it was only for very big accounts and with a specific contract with Microsoft.

In government contracts in the aerospace and defence, the semantic distinction blurs a little bit.

Government contracts are often inflated on purpose so that the work can leak towards other projects. Every country does that.

Hopefully false, and you need to increase that number to at least 20, more likely 30 to pay for the investment. That is very the problem lies - the risk.

Looking at the spaceflight calendar for the rest of the year, there are 6 flights where Ariane 5 could used, if you exclude all the national missions from non-EU countries. Let's round that to 10 as this does not cover all the remaining launches. So we are at a possible market of ~20 launches a year, with the current cheap prices of SpaceX. In order to justify reusability, Arianespace/Airbus would need to plan on having a 90/100% marketshare of the very competitive market, while their US competitors could benefit from quite lucrative military missions.

Oh yes there are enough of them. But to compete you need fair rules and open access to your competitors market, and that is not the case currently. What they are asking for is only the same protections as the US companies currently enjoy.

Yup, a mistake done in the 80s with Ariane 5 architecture, that we are still paying. Smaller scale means slower changes and this is being partially addressed with Ariane 6 and Vega C.

Similar issue with the use of solid propulsion, mainly used to also keep it in line with military needs.

Yes, Europe wants their own launchers anyway as the access to US launches is still a hazardous endeavour for critical payloads. And the recent moves of the US international politics are not going in the right direction.

As long as there is no reciprocity in the full access to the markets, we will live a semi-closed gardens. If the markets open, it won't take long for the European companies to develop a reusable launcher capability. The technology and the knowledge exists already, but there is no political or financial incentive to do that right now.

The Gripen is not Swedish?

Competition works when the market is open. But the space market is far from being open. Even building a satellite without including an ITAR or EAR part was politically impossible a few years ago for an EU company.

I believe the people behind peertube know about that. That is why Peertube is so much on federation with ActivityPub. If done properly this would allow anyone with an account on a website using ActivityPub (like Mastodon) to interact with the author of a Peertube video.

Granted this a both a technical problem (that I believe solvable) and a financing problem. It is hard to compete with the GAFAM and their advertising departments.

Agreed, if one could take into account all the subsidies, I am sure we would be at similar levels. The commercial cargo contract was on par with the ATV program, but the prospect is much bigger, with better financial stability.

And where should we stop counting subsidies? Are the government funded studies made by research institutes counted? They benefit a lot to the companies.

ESA has much less money than NASA and the DoD, and is free to chose a launcher from another country as well.

Are the European space companies subsidized by ESA and the other European space agencies? Yes. Is it much different from the subsidies in the US? Not really. Is the US space market bigger than the European market? Definitely!

To me this is a major reason why the reusable launchers were not developed in Europe. The concept was being studied but never gained traction.

One of the reason might have been vanity but if you look at it with the view point of a CEO from a European firm, reusability was a risky gamble:

1) In order to keep your manufacturing quality, one needs to produce a new rocket every two or three months. Beyond that, the people manufacturing it losses knowledge and unless quality assurance is increased a lot, you will losses quality.

2) EU was doing around 12 launches a year, and that was by being very cheap. You could plan on increasing the market share but that starts being difficult as a lot of what remains cannot use a European launcher for political reasons.

3) For the sake of the argument, let say cheaper price double the market share, that leaves 24 launches a year. Based on a manufacturing of 6 launchers a year, this leaves 4 launches per rocket. And that is with very optimistic numbers (doubling of marketshare, no issue with reusability).

4) If you look at the numbers from SpaceX, 4 launches per rocket is where the reusability starts making sense. But ideally, you want more. 5) The Airbus people have shareholders to account to, not a CEO who does not care risking going banqueroute while pursuing a dream to go on Mars.

So yeah, doable but much more difficult than in a market with better access to investment and to huge cash cows named NASA and DoD

The goal of the experiment is to test the harpoon itself. You could have a moving target but then it creates a constraint on tracking a non cooperative target and orientating your harpoon accordingly, which is quite a feat in itself. Also, by having it on the spacecraft, it allows observing the impact point later on with the in board cameras.

Yes, though depending on the part we are talking about it can take up to a couple of years. The mission has been designed to avoid creating small untrackable debris and everything is below the ISS.

Fun fact, as all the missions deployed from the ISS, the RemoveDebris satellite is already classified as a debris in the NORAD satellite catalogue.