To craft the proton tether, you will need the extracted sample and 150 pieces of silicone. Silicone can be found in abundance on AR-Y26. You can gain it by eliminating certain wildlife (Jellywaft, Skipper) or by searching for large clusters of yellow crystals. Shooting a cluster will grant you 50 silicone while killing wildlife will give you anywhere from 5-10. Once you have the necessary materials, you can return to the Javelin and Craft the Proton Tether.