Hitomi, which launched this February, has been silent since Saturday.
Scott and Mark Kelly attended Pleasantdale Elementary School in their New Jersey hometown.
The astronaut is about to come back to Earth after spending 340 consecutive days in space along with Russian cosmonaut Mikhail Kornienko.
The astronaut is scheduled to host a two-hour program Thursday at 5 p.m. ET.
"It's just a hypothetical planet, we haven't found it yet."
NASA are again proving why being an astronaut is amazing
A new crew is en route to the ISS. NASA TV has coverage of the docking and hatch opening.
It is nearly 40 times more difficult to get into NASA's Astronaut program than it is to get into Stanford.
A NASA mission reveals what happened to the water on Mars's atmosphere.
The agency is set to announce details on Thursday at 2 p.m. ET.
The next class of astronauts could head to the ISS, fly on NASA’s Orion or embark on a commercial crew spacecraft.
"Orion is being designed for missions far beyond low Earth orbit."
Just three months after the historic flyby, the New Horizons team has a paper coming out in the journal "Science."