No, seriously it is a telescope...
It's SOFIA mounted inside a 747 in order to do observations from higher up, in the stratosphere.
SOFIA stands for Stratospheric Observatory for Infrared Astronomy.
The lower atmosphere distorts infrared radiation levels reaching the surface of the earth, so this plane mounted one gets into the stratosphere for virtually undistorted observations.
That is why we put some telescopes in space, but that has some drawbacks.
Unlike space-based telescopes, SOFIA’s instruments can be exchanged, serviced or upgraded to harness new technologies. Its newest instrument, called the High-resolution Airborne Wideband Camera-Plus, or HAWC+, enables studies of celestial magnetic fields with ground-breaking precision.
And then images like the one below can be created that show what is going on magnetically and not just what we can see visually.
