Astronomers have photographed a new moon in our solar system using the Hubble Space Telescope. Mark Showalter, from the Search for ExtraTerrestrial Intelligence Institute (SETI), is intrigued that this planet “can have such a complex collection of satellites”.
Showalter and the rest of Team Pluto think that these moons are the result of big collisions between Pluto and another large object from the Kuiper Belt, the cloud of objects in the outer rim of the solar system.
According to Showalter, “the moons form a series of neatly nested orbits, a bit like Russian dolls”. The team believes that this new moon — the fifth after Charon, Hydra, Nix and P4 — indicates that there are more smaller objects that we can’t see from here.
Harold Weaver, from Johns Hopkins University Applied Physics Laboratory, says that “the discovery of so many small moons indirectly tells us that there must be lots of small particles lurking unseen in the Pluto system.”
This increases the danger for New Horizons, the spaceship now en route to the frozen dwarf planet and the Kuiper Belt at 48,000km/hr. That’s precisely why this team is looking into the planet, according to Alan Stern of the Southwest Research Institute, the mission’s principal investigator. “The inventory of the Pluto system we’re taking now with Hubble will help the New Horizons team design a safer trajectory for the spacecraft.”
New Horizons will give us the first close-up look of the dwarf planet, which used to be the ninth planet of our solar system before being demoted in 2008.
Perhaps the discovery of this new moon — between 10km and 25km across, and orbiting 93,000km around Pluto — will make fans of the ex-planet happier. Pluto was considered to be a solitary planet until 1978, when the United States Naval Observatory in Washington DC discovered Charon. In 2006, Hubble discovered Nix and Hydra. P4 was discovered in 2011. [NASA]