Tuesday, December 29, 2015

A Lander for NASA’s Europa Mission



- Final budget law for Fiscal Year 2016 regarding NASA’s Europa mission





























  1. I wonder if they have ever consider a relay communication spacecraft on jupiter's L1. If they'll have Juno in the following months, plus this, plus ESA's mission. A relay on L1 would increase science time while increasing data return. It could be in theory a 'basic' dish with some solar panels. Still have many doubts such as, is jupiter's L1 point inside of the planet magnetosphere? how much radiation harsh would it received at that point? how much fuel would it be needed to first put that probe in orbit and later on in L1?

  2. Jupiter's L1 is very far away from Jupiter. I don't see a reason for entering Jupiter's orbit to get to L1. It should take less fuel to reach it than to reach Jupiter's orbit, I'm not sure how much less. I don't think it would be that good though becouse at L1 relay would only be around 10x closer than Earth and visible at the same time as Earth. Perhapse if they found something else usefull to do at L1.

  3. I'd 'propose' a relay probe at L1, because it would give more space for science instruments in the main orbiters/landers and it will be always visible from earth (except obviously while solar conjuntion). An orbiter or lander would need a smaller antenna to transfer science data way faster and using way less power to something on jupiter's L1 than straight to earth. I think a jupiter's orbit insertion first o at least a fly by might be necessary because you need to decrease the speed of the probe in such a way to enter L1's orbit.

  4. You only need to circularize your orbit once you get to L1 by Hohmann transfer. I doubt you will get much benefits by talking to a small relay at L1 instead of 70m dishes on Earth.

  5. I think the L1 relay would be a good idea because of the inverse square law, the closer you are, the higher data rates and less power consuming you'll get. The author states that they might only could keep alive the lander for 10 days and if they add a seismometer they'll gather a lot of data, plus, the orbiter (1st scenario) could potentially only download that data every 10 days, which means it's a one limited time to get the data; if you have that relay at 1/3 AU (which is where I found jupiter's L1 is located from jupiter) you could transfer all that science data at higher transfer rates than sending those back to earth (2nd scenario) which is 4.2 AU farther in the best scenario, since europe's orbital period is 3 days and a half, you are going to be able to gather 3 sets of data instead of just a limited one.

  6. But you have a sqare law for dish sizes. You have 70m dishes on Earth, you would need a dish at least the size of spektr R 12x closer. That would cost hundreds of millions at least and be more usefull for VLBI anyway.
    And L1 and Earth would be very close on sky from Jupiter.

  7. The lander could be provided by ESA, the cost should be compatible with an M-class mission.

  8. As I understand NASA must build a lander. There is money for it. I would like to see ESA make an outer moons probe. It's the only place in the solar sistem where you can easily flyby large number of objects. There should be something interesting there.

  9. Unknown - The Europeans will be launching their JUICE mission to Jupiter in the early 2020s. It will study Jupiter, make two flybys of Europa, multiple flybys of Callisto, and will orbit Jupiter.

  10. Yep, orbit Ganymede. Thanks for the catch. I was thinking that while JUICE is usually presented as a Galilean moon mission, it will also do extensive studies of Jupiter from Jovian orbit prior to orbiting Ganymede.

  11. Could this Europa lander affect the space offered to ESA?
    If it does that would be very embarasing for NASA considering the past. It wouldn't be good if ESA starts to consider NASA as unreliable partner.


    Except for Huygens, which returned data directly from the surface of a different ocean world that may harbor independent life, of course.

  13. so, does this definitely mean that the ESA small spacecraft for the study of IO no longer has chances to be given green light? Too bad, it was a more efficent concept in all senses. Wanting to do everything at once is never wise.

  14. Re powering the lander -- has anyone ever looked into magnetic induction? If the magnetic field is large and fluctuating, it would seem a simple coil and diodes might produce useful charging current. After all we now recharge cellphones with induction. Why not a lander?

  15. Anon - You are right, Titan might also host life.

    Esther - It's not clear whether there will still be mass for a European contribution with the addition of a NASA lander. NASA may not yet know.

    David - I've seen several studies looking at magnetic induction to power Jovian orbiters, but never for a Galilean satellite lander. Since no orbiter mission has gone this route, the concept may either be considered immature or there may be technical issues.