Every object in the Pluto system now has a picture to their name. The tiny moon Kerberos was the last as New Horizons beamed the images back to Earth this week. And the blurry image came with a surprise.
Kerberos is smaller than NASA scientists were expecting. It’s surface is also highly reflective.
The above image was received by the New Horizons team on October 20th. It reminds me of Comet 67p with its double-lobed shape. The larger lobe is 5 miles across while the smaller lobe is 3 miles across. New Horizons’ science team believes the double-lobed shape could be the result of two objects merging.
The reflective surface comes as a big surprise. Kerberos is believed to be coated with relatively clean water ice.
Before New Horizons July’s close encounter, Kerberos was believed to be a pretty decent sized moon. Using the Hubble Space Telescope, researchers tried to judge how large Kerberos was based on its gravitational influence on nearby moons. This influence was a lot stronger than expected given how faint Kerberos was through the Hubble. The leading theory on Kerberos was that it was large with a surface covered with a dark material.
It turns out they were way off. Kerberos is smaller than expected and has a highly reflective surface.
“Our predictions were nearly spot-on for the other small moons, but not for Kerberos,” said New Horizons co-investigator Mark Showalter.
Now, researchers want to understand why their initial prediction was so far off.
Next mission begins (hopefully)
A mission extension hasn’t been formally granted, but that’s not stopping New Horizons from conducting a series of initial targeting maneuvers. The first of four maneuvers designed to send the spacecraft to Kuiper Belt Object 2014 MU69 was completed yesterday. New Horizons fired two of its hydrazine-fueled thrusters for 16 minutes. This changed the spacecraft’s trajectory by about 10 meters per second.
Artist impression of KBO and New Horizons. Credit: NASA
The four maneuvers will change the spacecraft’s trajectory by 57 meters per second and put it toward a possible close encounter with MU69 on January 1, 2019.
Right now, New Horizons is 74 million miles past Pluto and 3.16 billion miles from our little blue marble. The spacecraft is in great shape and continues to downlink data from its Pluto encounter back to Earth.
“Even as the New Horizon’s spacecraft speeds away from Pluto out into the Kuiper Belt, and the data from the exciting encounter with this new world is being streamed back to Earth, we are looking outward to the next destination for this intrepid explorer.”
Grunsfeld added, “while discussions whether to approve this extended mission will take place in the larger context of the planetary science portfolio, we expect it to be much less expensive than the prime mission while still providing new and exciting science.”
Last summer, the Hubble Space Telescope began looking for another target for New Horizons. Five objects were discovered, and 2014 MU69 was selected. Scientists estimate MU69 is just under 30 miles across. That’s about 10 times larger than the comet the Rosetta mission is orbiting.
Scientists are itching for the opportunity to better study a Kuiper Belt Object (KBO). Objects like MU69 are believed to be the building blocks of Pluto. And they could provide scientists with a snapshot of what the outer solar system was like after our solar system formed more than 4 billion years ago.
“There’s so much that we can learn from close-up spacecraft observations that we’ll never learn from Earth, as the Pluto flyby demonstrated so spectacularly,” said New Horizons science team member John Spencer. “The detailed images and other data that New Horizons could obtain from a KBO flyby will revolutionize our understanding of the Kuiper Belt and KBOs.”
The New Horizons team will submit a proposal that will be evaluated by an independent team of experts. After that, NASA will make a decision on whether to approve an extended mission. After the incredible images of Pluto, how can you not approve an extended mission?