Earlier this week, after years of trying, Iran told the world that it finally achieved one of its major goals and launched a monkey into orbit, paving the way for a manned flight.

The monkey was even returned to Earth successfully, according to reports. Iranian TV showed the monkey — unhappy looking but alive — back on Earth after its trip.

However, Internet users have gone over the photos released by Iran's FARs news agency, and many believe that the monkey shown in photographs back on Earth is not the same monkey that went up to space.

As the Independent points out in this photo, the monkey that went to space (right) appears to have a large birthmark over its eye. The monkey that returned to Earth (left) has no birthmark in this place.

France24 also points out that images of the launch have been shown widely in Iranian state media, but images of the rockets return to Earth are conspicuously absent.

The U.S. government had expressed doubts about the monkey's voyage at the time.