Astra

Astra (アストラ, Asutora?) is the younger brother of Ultraman Leo. He came to earth after learning that Leo had survived the destruction of their home planet Nebula L-77 and appeared several times in the series, assisting him several times when the odds were stacked against Leo.

Ultraman Leo
The younger brother of Ultraman Leo, Astra came from the desert Nebula L77 of the Leo constellation. After the destruction of L77 by the Alien Magma, Leo, Astra, and Leo's pet monster Ron were the last survivors, but Leo thought he was the last of his kind. As Leo and Ron landed on Earth, Astra was captured and held prisoner by the Alien Magma until he was eventually rescued by Ultraman King. After King told him of Leo's survival, Astra headed for Earth and rescued his brother during a battle against Garon and Littre. Ever since Astra has saved Leo against several different aliens over the months that were too powerful for Leo to defeat himself. At one point Alien Babalou froze Astra in a special type of ice in space and took his identity as he stole the Ultra Key. After Ultraman King revealed Babalou for what he was Leo saved Astra from his icy imprisonment, defeated Babalou, gave back the Ultra Key, and the two brothers became the first Ultra Brothers that were born outside of Nebula M78. Astra continued to help Leo after helping him destroy the Saucer Monster, Hangler.