The couple both have a bland expression (which may have been an attempt to avoid anything that could be interpreted as hostile) and the man is seen raising his right hand with the palm facing the viewer. While this gesture clearly conveys a greeting when viewed by another human, an extraterrestrial may have no way of interpreting this gesture. (Could you interpret a gesture made by an antelope … or a praying mantis?) It does show, however, that humans have opposable thumbs, as well as the general range of motion of the upper limbs.

With regards to the scientific data presented, the top left of the plaque shows the hyperfine transition of neutral hydrogen as a means of conveying to the reader baseline units of time (0.7 nanoseconds, the frequency of the transition) and distance (21 cm, the wavelength of the light released by the transition). If one is able to deduce that the image is that of hydrogen, the time and distance should be understandable.

The plaque also contains a map of our Sun relative to 14 pulsars as well as the center of our galaxy, conveying both the distances to the pulsars and their frequency in binary notation. As this image conveys copious objective data, a spacefaring species might well be able to easily interpret it.