Is Allah in the lowest heaven all the time?

One question always bothers me about tahajjud . I hope some one can help me with it. A hadith says: > “Our Lord Descends to the lowest heaven during the last third of the night,” And I am in this part of the earth third part of the night. But on the other side of the earth is afternoon. (SeekingOfTruth.com ) But Allah swt is all above the universe. So is Allah swt in the lowest heaven all the time? Hope my question is not so stupid. :)