Collecting ASTONISHING THOR #1-5.
The God of Thunder faces the fury of living planets! When terrible storms threaten to tear our world apart, Thor traces the cause to Ego, the Living Planet - out of his orbit and rocketing across the solar system on an unstoppable quest to rescue his long-lost brother, held captive by the cosmic entity the Collector. But there will be no happy reunion at the end of his journey - for when Ego and Alter-Ego meet, only one can survive...and Earth surely will be destroyed. Only Thor has power enough to avert the pending apocalypse - but to do so, he'll have to rely on the help of a wind goddess with questionable motives...and a stormy history with the God of Thunder.