Professor Ochanomizu

Doctor Elefun from the NOW Comics version of Astro Boy

Professor Ochanomizu is generally portrayed as the head of the Ministry of Science in the Astro Boy series. He is relatively portly, and has a large elongated nose which is his most sensitive area. Sometimes he is involved in nose fights it tends to falls off. His other notable features are the white fluffy tufts of hair that wrap around his head in a male-pattern baldness style.

Ochanomizu is portrayed as a caring father figure to Astro. After Doctor Tenma abandoned him, Ochanomizu has always gone to great lengths to retrieve him. The character is a supporter of robot rights, and believes that humans and robots can co-exist peacefully, as opposed to Tenma. He is the only major human character to support this view, with the majority opposed to it (such as Acetylene Lamp). Ochanomizu also has the belief that robots can think for themselves and can behave like humans, extending Astro's robot family to include his parents, younger sister Uran and also older brother Cobalt. Although the fact is that Astro is indeed a robot hero, he also wants Astro to be a regular human boy. Due to this, he often sends Astro on missions and repairs him when needed.

In Astro Boy, Ochanomizu (known as "Dr. Elefun") is a colleague to Doctor Tenma. He implants the mysterious, extraterrestrial life, "blue core" in the body of Astro Boy to power him. When Tenma decides to abandon Astro for not being human-like, Ochanomizu tends to be more caring but does not share his view. He pleads on behalf of Astro every time he appears such as when he tells that even though he can't see the future, he tells Astro that he just has to find his place in the world. He also seems to not like President Stone trying to use the Red Core due to its power. He is voiced by English actor Bill Nighy who also voices Robotsky of the Robot Revolutionary Front in the film.

While the usual English version of the name Pakadermus J. Elefun is a pun related to the character's nose and appearance, in the Japanese version, the name Ochanomizu stands for "Tea Water", which is also a neighborhood in Tokyo. It is unknown if his family members (which are never mentioned) have the same nose, however in the manga Pluto he is shown to be a widower with a granddaughter, who appeared briefly. Much of the character's background is also left unexplored, although in the 1979 movie Undersea Super Train: Marine Express, he reveals that he was from Polynesia. In Atom: The Beginning, Hiroshi Ochanomizu has a sister called Ran.