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ESA advances its plan for satellites around the Moon
- _Microft 5y agoMaybe something like this could be created comparatively easily and inexpensively. NASA tested optical communication to Moon in 2013 already [0], so the technological readiness level of some highspeed transmission technology should be quite high already. If such an optical communications module were installed on a sat that could also talk to off-the-shelf Starlink sats, this satellite could serve as relay that connects Earth to a (very?) small constellation of Starlink satellites. Beside the bespoke relay satellite, this might be a rather inexpensive solution (Starlink satellites are cheaper than $500k per piece already, as far as I know). A counterargument I can think of is that Starlink satellites might not be hardened enough to work outside of Earth's protective magnetic field. [0] https://en.wikipedia.org/wiki/LADEE#Lunar_Laser_Communication_Demonstration https://en.wikipedia.org/wiki/LADEE#Lunar_Laser_Communicatio...
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- BuyMyBitcoins 5y agoI know that most orbits around the moon are unstable because of uneven mass distribution. So I don’t know how the shape of constellation will affect things.
- _Microft 5y agoLunar mascons (mass concentrations) are only an issue for low lunar orbits ("LLO") which we are not talking about here. In fact you would want to maximize distance, not minimize it, so each satellite can cover a larger area on ground.
- geertj 5y agoInteresting tidbit about lunar orbits: due to mass concentrations in the lunar subsurface, there are only 4 stable low lunar orbits.
- valuearb 5y agoThere are many lunar orbits low enough and stable enough to be useful for crewed exploration. The HLS will be in one. That Gateway won’t be. It’s only the super low orbits that the masscons screw up.
- valuearb 5y ago“ a commercially viable constellation of lunar satellites”???? “ Commercial bodies could use innovative technologies developed for the Moon to create new services and products on Earth, which would create new jobs and boost prosperity.” You know what the engineers working on this project could have been doing instead? Work on projects that directly benefit earth even more. Instead of this pork barrel project without a direct use. The biggest factor by far in making lunar exploration and development cheaper is mastering in-orbit refueling. That enables hundreds of tons of cargo to be cheaply delivered to the lunar surface. That means easily building lunar satellite constellations when needed. It also means we won’t need the bloody sores of the Gateway to Nowhere and SLS bleeding exploration programs dry.
- edgyquant 5y agoI will never understand this attitude. Large nation states are able to work on more than one thing and expanding capabilities on and around the moon will directly benefit the Earth one day.
- mturmon 5y agoYes. Facilitating communications is just a general good thing. The improvised relay system we have around Mars has been important to fast relay of data from the rovers. It has also allowed us to more closely observe EDL sequences so that if something goes wrong, we will learn what it was so we can fix it.
- IshKebab 5y agoThat's not guaranteed by any measure. Projects can just be a complete waste of time.
- wolverine876 5y agoI don't understand the parent response: I'm sure you know that money, time, and talent are all constrained, and everyone, from a child with an allowance to the CEO of Google to the President of the U.S. has to choose priorities. All of economics is about allocating those resources. Even within NASA, they have to choose some project and reject many more.
- nickserv 5y agoInteresting that they mention observation stations on the far side of the Moon, when these satellites would presumably disrupt certain observations. Obviously the level of interference will be much much less than on Earth or even Earth orbit. But for really pristine observation it seems the Lagrange points are better candidates. In any case pretty excited about this. Having it run by the EU will hopefully make it more of an equal access than if it was run by the US or China.
- throwaway894345 5y agoHas the US been very stingy about its space science? I always thought NASA in particular was pretty internationally collaborative (or at least no less so than ESA)? In whichever case, I’m excited for other countries (or unions of countries) to join in on space science.
- nickserv 5y agoThe US specifically bans most cooperation with China.
- themgt 5y agoSeems heavily over-hyped. Video I found was: https://www.youtube.com/watch?v=8kUI4YtG0xY https://www.youtube.com/watch?v=8kUI4YtG0xY Which links back to: https://www.sstl.co.uk/what-we-do/lunar-mission-services https://www.sstl.co.uk/what-we-do/lunar-mission-services Looks like this is a better article: https://spacenews.com/esa-awards-study-contracts-for-lunar-communications-and-navigation-systems/ https://spacenews.com/esa-awards-study-contracts-for-lunar-c... The European Space Agency has issued contracts to two European industry groups to begin concept studies of lunar satellite systems that would provide communications and navigation services. "to begin concept studies" ... afaict they have no satellite hardware built and no rocket launches booked. The NASA HLS Starship selection really has thrown the entire Artemis program and associated space pork into limbo. If you're landing 100 tons of payload on the Moon on a reusable/rapid launch rocket stack this entire sort of proposal "let's put together a working consortium to study launching one pathfinder lunar comms sat in 2023 and then study perhaps launching up to a handful more undefined years later [at a cost of $100 million per launch]" is just going to become "SpaceX dumped 100 spare Starlinks into lunar orbit as a rideshare on this week's mission, so now we have Moon internet"
- dougmwne 5y agoAnd Starlink Moon edition will have a paltry 2.6 seconds of roundtrip latency to Earth. Mars colonization gets all the hype, but who in their right mind would want to be a 40 minute roundtrip ping from the nearest AWS location?
- oceanswave 5y agoI guess it’s going to be Microsoft landing a datacenter-in-a-shipping-container on Mars before AWS does something similar at the rate that Blue Origin is going.
- dougmwne 5y agoI am legitimately jealous of the engineer that gets to design how that CDN cache operates.
- jasonwatkinspdx 5y agoI don't know why people are automatically assuming you could just do this with off the shelf starlink sats instead. There's a huge difference between an optical link in LEO that goes a couple 100 km, and the moon which is nearly 400,000 km away. The link has to be bidirectional and I don't see how existing starlink sats would have anything close to the optics or antennas required for that. Let's not turn enthusiasm for starlink into poo poo-ing all over any other plan for something in space. The ESA just wants concept studies on what might work. That's perfectly reasonable.
- _Microft 5y agoThere are only two comments mentioning Starlink, one of which is mine. As the other one does not go into details, your comment seems to be talking about mine and seems to be based on a misunderstanding of what I wrote. Feel free to ask if there is still something unclear after reading it more closely.
- jasonwatkinspdx 5y agoIf I wanted to reply to you directly I would have. I did not precisely because I was hoping to avoid defensiveness from any particular poster. That said the logical place to put your relay would be L1, which is still some 60,000 km from the moon. It's not at all clear that off the shelf Starlink sats would be capable of communicating that distance from their orbit over the moon. You'd also need the earth side of the relay, which also clearly cannot be the existing Starlink cluster. They'd be foolish to not consider a Starlink derived design or SpaceX as a vender, but I don't think this can be done as inexpensively and quickly as your comment suggests.
- labster 5y agoMaybe Starlink with a single ground station? I know landing makes it so much more complicated, but those Starlinks can communicate back to the station on the lunar surface easily, and the station stays pointing towards Earth on the near side. SPOF though.
- Havoc 5y agoNot quite clear on how this will be "commercial"? Not much demand for netflix on the moon I suspect
- helgee 5y agoDisclaimer: I am one of the (many) engineers working on the project. Before COVID I worked for a European lunar exploration startup and access to a constellation like this would have changed everything. The plan was to provide an end-to-end payload transportation service to the lunar surface and we wanted to fly our own two rovers as a demo mission. While you can accomplish all communications (TM/TC, HD video) and navigation (orbit determination, surface nav) tasks with terrestrial ground stations, it is hellishly expensive. Just as an example, the good thing about the Moon (in contrast to Mars) is that it is very close and you can drive a rover almost in real time due to the comparatively low latency (that's what the Russians did with the Lunokhods: https://en.wikipedia.org/wiki/Lunokhod_programme https://en.wikipedia.org/wiki/Lunokhod_programme). That means you can cover more ground than on Mars which was also very important to us because the plan was to drive to one of the Apollo landing sites (where you must land outside the exclusion zone) and we would have had only 10-12 days of daylight for our operations until the lunar night would have killed our electronics. For that you need good video feeds from the rover's cameras which again required downlink via X band antennas due to the Moon's distance from Earth. There are not that many X band ground stations and all the interplanetary missions are constantly fighting for the limited capacity. We would have then needed even more ground station time for ranging operations, i.e. performing orbit determination during the transfer and prior to landing and determining the rovers' exact positions on the surface. In the end, we would have needed to pay several million EUR for ground station time alone. A reasonably priced Project Moonlight constellation would have been a godsend and significantly reduced the complexity of our operations. Cash-strapped startups are not the best customers, though... I can only assume that all the companies in the NASA CLPS program are facing the same issues. The problem is that they are planning their missions and are designing their spacecraft now. If this constellation becomes a reality, it will certainly be too late for the first batch. As for the ideas about Starlink, satellites are designed around their payloads, i.e. all subsystems (power, thermal, comms, on-board computer, propulsion) are designed to fulfil the requirements of a specific payload and its mission with some margins. Very rarely can you swap or add additional payloads without redesigning the whole system especially if your starting point is as streamlined a design as Starlink's is. I am a huge fan of all things SpaceX but they are not miracle workers. Also Starship has not reached orbit (yet) and Super Heavy has not flown (yet). Finally, the costs. As some others have commented, this is a paper study right now which is comparatively cheap (no idea how much exactly but my educated guess would be single digit millions). Whether this will be funded for real and becomes an actual program will be decided at ESA's next ministerial. In the grand scheme of things this is not a lot. Compared to of ESA's annual budget of ~6 billion EUR it is almost negligible. That again is a joke compared to NASA's annual budget of ~22 billion USD. Which still pales in comparison to the up to 1.3 trillion EUR that the German federal and state governments alone spent on the mitigation of the pandemic (https://www.zdf.de/nachrichten/politik/corona-novemberhilfen-dezemberhilfen-kosten-bartsch-102.html https://www.zdf.de/nachrichten/politik/corona-novemberhilfen...) or the economic cost of climate change which is also in the trillions. Yes, space hardware is too expensive, there is too much red tape, and frankly too much nepotism in OldSpace. But taking the few billions spend on space every year away and spending them on the "big problems of our time" would accomplish very little. TL;DR: The technical benefits are real whether it becomes a reality and is commercially viable remains to be seen. SpaceX is great, Starship is great, Starlink is great, but it is also not magic. Space sounds expensive but really isn't when you do the math.