back to article Like Uber, but for satellite launches: European Space Agency’s ride-sharing rocket slings 53 birds with one bang

The European Space Agency (ESA) has successfully demonstrated its Small Spacecraft Mission Service dispenser by slinging 53 satellites from a single rocket. Thursday’s launch was the first time the ESA has used its Vega launcher since 2019’s effort - which dunked satellites in the Atlantic Ocean. This time around no problems …

  1. iron Silver badge
    Boffin

    > With the likes of SpaceX, Virgin Orbit, Jeff Bezos’ Blue Origin and Rocket Lab all offering launch services...

    ROFL! Come back to me when BO actually have a working rocket and Branson stops redefining orbit so his poxy plane can reach it. That sentence should read:

    With SpaceX and Rocket Lab offering launch services...

    1. John Brown (no body) Silver badge

      Virgin also have a converted 747 Jumbo for space launches. That's Virgin Orbit, not Virgin Galactic. Virgin orbit has successfully launched one orbital rocket. The rocket flight itself was less successful.

  2. Locomotion69

    Great!

    More crap in space to increase chances for satellite collisions.

    1. My-Handle Silver badge

      Re: Great!

      At around 500km high, nothing without it's own propulsion is going to stay up there long. Atmospheric drag is still a factor and will pull most things down out of orbit.

      Hell, even the ISS (at an orbit of around 400km) needs a periodic boost so as not to fall out of the sky.

      1. JCitizen Bronze badge
        Trollface

        Re: Great!

        Holy crap! So you are saying that these cube sats are above the ISS orbital path and could end up crashing into it on the way down? I shudders the thought!

  3. Roger Kynaston Bronze badge

    ESAIL I'm confused

    As a mere yottie rather than commercial skipper of supertankers I am happy to be wrong but ...

    My understanding is that AIS works on VHF radio - hence being strictly line of sight. I uses a GPS receiver to work out position, speed and course which it then blats out to anyone who can receive it. It therefore works a bit like aircraft transponders. My confusion then is how a satellite fits in.

    1. Cuddles Silver badge

      Re: ESAIL I'm confused

      As the article notes, it's line of sight and so limited to around 70km because of the Earth's curvature. If you can bounce the signal off a low-orbit satellite, you can pick it up from a lot further away than that. The satellite effectively extends your line of sight.

      1. Spherical Cow Bronze badge

        Re: ESAIL I'm confused

        The article states a range of 74km, and if you think it's an oddly specific range that's because it has been converted from 40 nautical miles.

    2. Cynic_999 Silver badge

      Re: ESAIL I'm confused

      "

      My understanding is that AIS works on VHF radio - hence being strictly line of sight.

      "

      Yes, you are correct - hence the advantage of using satellites. AIS uses two frequencies, 161.975 MHz and 162.025 MHz (marine channels 87 and 88), using short burst data transmissions at essentially random intervals so there is an acceptably low percentage of radio collisions even when a lot of ships are in radio range.

      A satellite has line of sight to a very large area of ocean, and so a constellation of satellites can receive the AIS transmissions from ships over a vast area (almost the whole World), and relay the data back to ships or ground stations on the surface. Similar to how an EPIRB is VHF (and so line of sight), but is picked up by satellites and relayed to rescue services even though the EPIRB signal is out of range of any surface receiver.

      The average port cannot receive AIS signals (or radar returns) from ships further away than 50 miles or so (line of sight), but satellite relays would provide ports with a similar tool that air traffic controllers enjoy with aircraft transponders (SSR), and so have greater advance warning and be able to plan how to handle the traffic better.

    3. JohnG Silver badge

      Re: ESAIL I'm confused

      As I understand it, ESAIL is aimed at monitoring of ship positions for environmental/fisheries management, fleet management, security, etc., collecting AIS data from areas that are beyond the range of terrestrial monitoring stations.

  4. John Jennings Bronze badge

    AIS

    AIS comes in 2 classes - A and B (and B+)- A is commercial, B is recreational. A is 5 watts, B is 2 watts, with the + outputting at 5.

    proper installation of Class A specifies 15M above sea level - hence the 74KM range

    The range of B (and B+) is highly dependent upon the areal and its placement. As AIS uses 2 channels (either side of the DSC radio channels), a standard marine radio areal may not transmit at ideal frequencies - and placement can also be problematic (getting it high enough, where it doesnt interfere with the DSC areal, lines, etc.). I have seen AIS B which doesnt pick up a target more than 10KM away!

    The satellite will be great for the system - its generally ships that recreational boats need to watch/avoid.

    1. JanMeijer

      Re: AIS

      VHF and 5 watts sounds remarkably similar to what I remember of the specs of personal locator beacons, the signals of which also are picked up by (receivers on) orbiting satellites.

      I'm guessing that's not a coincidence, you wouldn't have any knowledge of (pointers about) that, would you? Curious!

  5. John Brown (no body) Silver badge

    Like Uber, but for satellite launches

    Just wait. Give it a few years and there'll be minimum wage rocket jockeys clogging up the space lanes touting for work

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