Now Ye're Talking - to the team for Ireland's first satellite, EIRSAT-1

DeVore wrote: »

How can the general public / interested bystanders get involved or follow the launch etc?

We are very keen for the public to follow our journey! There are some exciting plans for our public engagement and outreach events, so stay tuned for more once we get our documents finished.

In the meantime you can have a look at our website www.eirsat1.wordpress.com. We have an active blog detailing the weekly activities of the team and information on our payloads and team members.

Follow us on Twitter for daily updates and any events! @EIRSAT1

DeVore wrote: »

So many questions about this... its just so insanely complicated to tackle this I'm in awe!

Ask as many as you like! That's what we're here for - no question too simple or complicated!

diomed wrote: »

On Friday, 4 October 1957, the Soviets had orbited the world's first artificial satellite. Anyone who doubted its existence could walk into the backyard just after sunset and see it. — Mike Gray, Angle of Attack

I saw Sputnik, or my father or uncle told me that was what we saw.

How many satellites have been launched since then?

That's an interesting question! What counts as a satellite? Does the Space Shuttle count even though it's the same object that's been put into orbit multiple times? That's probably open for debate!

The best answer I could probably give you is the number of International Designators that have been assigned by COSPAR, the Committee on Space Research. COSPAR do count each Shuttle launch as a separate satellite. To date, they've assigned 7821 designators to spacecraft. And the first one is 1957-001B for Sputnik.

In case you're wondering, 1957-001A would be the rocket that put Sputnik into orbit, but rockets aren't included in the 7821 spacecraft, so we're just counting the satellites themselves (even though rockets can spend a long time orbiting the Earth after their job is done and by some definitions would count as a satellite).

diomed wrote: »

How many circuits will the Irish satellite do, how many days/years will it be orbiting?

EIRSAT-1 will be launched from the ISS and so it will have very similar orbital properties as the ISS. That means we'll get 16 orbits per day. Assuming we stay in orbit for a year, that's 5840 orbits, or over 250 million kilometres! But hopefully we'll manage to stay in orbit a bit longer than that.

diomed wrote: »

Is there a central record of the research by all the satellites that were put up?

There's not really any central record. For a start, not every satellite is doing research, communications satellites are a good example. Even then, some communication satellites would be funded by nations but a lot of them are commercial endeavours and companies might consider anything that they learn from operating a satellite to be commercially sensitive and not want to share it.

But of the satellites that were intended to do scientific research, that would work exactly the same way that science in general works. There's no central record, but different disciplines of science would have a small number of scientific journals that are well respected within that discipline. And the scientists that work on the satellites will want to publish their research in the most well respected journals that get the most subscribers so that their work has the most influence.

diomed wrote: »

Could we be researching something already researched?

Possibly, but it's incredibly unlikely. Again, this works the same way that science works. When you have an idea, or you decide you want to research a certain topic, the first port of call is the library (or the internet). You do a literature review and you try to learn as much as possible about that topic from other people's research. Once you've done your literature review, you might identify a gap in the collective knowledge of science and decide you want to answer some of the questions that no one knows the answers to. Could some one have researched it before and kept the answers to themselves? Maybe. I think it's unlikely because scientists will want to publish to make sure that their name is associated with this knowledge and they get the proper credit for discovering it first. But even if it had already been researched, if that knowledge was kept private then it could be worth researching it again so the knowledge can be made public.

Philosophically speaking aside, we've got a lot of new technology on board that take advantage of new advances in in materials science so it's very unlikely anyone has ever put together anything quite like this before. And we're going to use the data it collects to do astrophysics and study exploding stars in other galaxies. I can say with absolute certainty that if we see a new gamma-ray burst from another galaxy, no one has ever seen that before!

Thanks for the questions!

Tom Dunne wrote: »

I love this line. I have visions of a postgrad shaking the device like a cocktail shaker.

While postgrads are a lot cheaper than a proper vibration test table, they just can't reach the frequencies we need! We'll be testing in facilities at Resonate Ltd in Newry as well as at the European Space Research and Technology Centre (ESTEC) in the Netherlands.

We'll also be doing thermal environment tests and these tests are often collectively called "Shake & Bake".

Tom Dunne wrote: »

I was coming in here to ask you about how what are doing might compare to CubeSat, something I have great interest in and then I see you are using CubeSat. Do you have to assemble it in a cleanroom-type environment?

Yes, but not to a very high standard of clean. We'll need a class 100,000 cleanroom for the flight hardware. We're hoping to kit out a room on the bottom floor of the UCD Science Centre which already has a large glass wall. That way the public will be able to watch us work and see what we're building.

GMOD, the gamma-ray module, has some optical components and for that it's usually recommended to assemble in a class 10,000 cleanroom. But that assembly shouldn't take too long so we'll perform it in another borrowed cleanroom and once all the optical interfaces are safely on the inside of the GMOD enclosure, we can transfer it to our own one and integrate it into EIRSAT-1 there.

Tom Dunne wrote: »

One of the things the space race in the US has had an effect on is the spin-off industries, with those that work on such programmes having very transferrable skills, plus the potential for spin-off companies. While I acknowledge we are very much at the embryonic stage here in Ireland, do you see potential to develop a "space industry" here?

Now if I could only convince my educational institution to get interested...

The space industry already exists in Ireland, primarily due to our membership of ESA. As you might know, ESA have a policy called geo-return. Money that Ireland spends on ESA is money spent in Ireland by ESA. But the industry is nowhere near as big as it could be and one of the stated goals of the EIRSAT-1 mission is to change that.

We need more graduates with the knowledge and skills necessary to compete in the space industry and make Irish universities and companies more competitive in the global space industry. We think that the best way to achieve that is by to get first hand experience of actually building and operating a spacecraft.

Thanks for the great questions!

Rubecula wrote: »

What is the orbital period? and will it be visible from the ground using mark one eyeballs?

The orbital period will be approx 92 minutes. I'd say it's probably not going to be visible to the naked eye. If you get really lucky you might catch a reflection of the Sun off one of the solar panels or something, but it's not something that would be predictable or that you could rely on happening.

Rubecula wrote: »

No chance of retrieving it at end of mission I suppose only it would be great in a big display in the Uni. (Or anywhere suitable)

Sadly no. It's launched with some (small) velocity from the ISS so that means that the distance between the two will just continue to grow. As well as that, EIRSAT-1 will be in a decaying orbit due to atmospheric drag while the ISS is re-boosted periodically to maintain its altitude. Also, EIRSAT-1 isn't designed with the correct grapple (or any grapple for that matter, it just has the rails it needs to smoothly exit the deployer) to allow it to be picked up the robotic arms on the ISS.

It would be amazing to have the real thing on display after having been in space. But realistically, there's not a lot of stuff that goes up there that comes back in one piece. We'll just have to make do with maybe the engineering model or some other mock-up.

Thanks!

Rubecula wrote: »

In the planning stage, what consideration did you give to space junk? With so much up there a safe orbit must take a lot of maths and study?

Space is big. Really big. You just won’t believe how vastly hugely mindbogglingly big it is. I mean you may think it’s a long way down the road to the chemist’s, but that’s just peanuts to space.

Sorry, I couldn't resist. You're right that there's a lot of stuff up there, but for now, there's also a lot of empty space. And that empty space is really necessary to ensure that the probability of collision remains as low as it is.

There's basically no way to find a 'safe' orbit during the planning phase. It would be crazy to try and accurately propagate EIRSAT-1's orbit for the lifetime of the mission. And that's before we've even get to launch, so to know it now, we'd have to figure out exactly where the ISS will be in 2 or 3 years when we'll launch from it. We'd also need to know the masses and forces of all the separation springs of the other CubeSats that we're sharing a deployer with to calculate our initial launch trajectory. And that's just for EIRSAT-1, we'd have to do the same thing for everything that could potentially hit it! Essentially what I'm trying to get at is that predicting a collision so far out is not a problem that can be solved.

Since a lot of satellites like EIRSAT-1 have no means to alter their orbit to avoid a collision, it's very important to keep space as empty as it currently is. So that means we have a responsibility to other space users to make sure that we don't end up as space junk. Any mission launched into space must have a plan for how to they intend to deal with the disposal of the spacecraft after the end of the mission. The rules are that you have 25 years after the end of the mission to de-orbit the spacecraft or boost it into a parking orbit where it doesn't pose a risk to active spacecraft.

With EIRSAT-1 we're expecting a 1 year (2 years at most) lifetime before the spacecraft de-orbits due to atmospheric drag, so we're in no danger of violating the rules. But we didn't get off the hook that easily, we still had to prepare a full 'Space Debris Mitigation Report' for ESA.

Ger Roe wrote: »

This isn't a scientific question, more of a self confirmed space geek one...

I have a small collection of NASA mission patches that I have collected over the years, do you have a patch for your mission logo design and can it be purchased anywhere?

We hope to have some mission patches soon! I'm getting ready to sew it onto my denim jacket.

Ger Roe wrote: »

Best of luck, by the way.... I look forward to also collecting the inevitable commemorative postage stamp when it is issued.

(I'll get my coat now)

Thanks so much! The stamp may be a few decades away, if we still use stamps...

Edit: Send us a PM with your details and we'll make sure to pop a mission patch in the post to you as soon as we get them! Sorry it won't have an EIRSAT-1 stamp on the envelope.

DeVore wrote: »

If you dont launch it on March 17 and call it Sat Paddy Day then I will never speak to you again

Well it's been nice talking to you.