The grim task of searching for the scores of people missing from the devastating flood that struck Texas Hill Country nearly a week ago is taking an agonizing toll on searchers.

NASA’s high-altitude WB-57 aircraft took off from Ellington Field Joint Reserve Base in Houston on Tuesday, and will conduct aerial surveys using its DyNAMITE (Day/Night Airborne Motion Imager for Terrestrial Environments) sensor.

Fire crews and trained search dogs from the Bay Area have been deployed to Texas to assist in ongoing rescue efforts as catastrophic flooding continues across the state. As of Wednesday, more than 160 people were missing and at least 100 have died, according to the Associated Press.

Austin nonprofit pet shelter Austin Pets Alive! is leading the efforts to find animals in the wake of the deadly flooding. Here's how you can help.

Various actors make celebrity-centered posts like these, which are common after a disaster, said Cliff Lampe, University of Michigan professor of information. These go viral because fans of celebrities want them to be seen doing good things, "which by extension means they are good people, too," he said.