A radiation shield would not generate bursts of electrical arcs and would not have electrical towers to generate it. This is an electrical force field that would shock anything coming between the towers, allowing current to jump the space.
They went to Alpha, how could they have missed that it is not a planet but a moon? The mother planet should have been visible to them all the time, a moon is much smaller and it cannot just hide its mother planet, unless you are very near to it, but they had approached Alpha from faraway point, so, not the moon, but the planet should have come to their notice first. And moons normally orbit their planets at a much faster rate, so they to to chase the moon orbiting around the planet, that would have revealed the planet. And the time Bellamy Clarke awoke, and Jordon was awake even earlier, and rest of the main team awoke, had their daily chores, ate foot, etc. was enough time that the planet could have come to the notice. And when Jordan and Raven eventually notice the planet coming out from behind the moon, it was rising fast, that it could not have had a very long time period between setting and rising. If Monty and/ or Harper had discovered Alpha, they should have noticed its mother planet. Actually, their first target to explore should have been the mother planet, and only after the planet was not found worth survival, one could have thought about moon.