Meet the solar system's dwarf planet's tiniest moon, Kerberos. Recent photos received by NASA last Oct. 20 from the New Horizons spacecraft showed the astonishing images taken from the Pluto family during a flyby three months ago.
Completing the already discovered Pluto's Charon, Nyx, Hydra and Styx, Kerberos seems to appear not as what experts have been expecting. The recently found moon was thought to be bigger compared with Styx and darker, but the images appear it may have the same size or even smaller and brighter.
"Once again, the Pluto system has surprised us," Hal Weaver of John Hopkins University Applied Physics Laboratory's New Horizons project scientist said. The moon appears to have two lobes where the larger one is estimated to be 5 miles (8 km) in size, while the smaller one around 3 miles (5 km). Just like the other moons in Pluto's satellite system that appeared to be shiny or reflective, Kerberos is also enclosed with a water icy surface.
Researchers "theorized that Kerberos was relatively large and massive, appearing faint only because its surface was covered in dark material," New Horizons team members said. "But the small, bright-surfaced Kerberos now revealed by these new images show[s] that that idea was incorrect, for reasons that are not yet understood."
Before the flyby, scientists were already trying to study the moon's characteristics using the Hubble Space Telescope. By calculating surrounding objects' impacts to its gravity, they tried to "weigh" the moon. "Our predictions were nearly spot-on for the other small moons, but not for Kerberos," Mark Showalter, co-investigator of New Horizon stated.
New Horizon's flyby dataset is reportedly still being sent. And all the photos, dimensions, and other relevant information last July are expected to arrive August and September next year. Although Kerberos is a two-lobed satellite, its name came from the guardian of the underworld, the three-headed dog Cerberus.
