It’s been a decade in the making but today, after such a long wait, we can now see Pluto and Charon for what they are.
And they’re absolutely stunning.
The image on the left is the high resolution image taken by the LORRI camera a few days before its closest approach (which you’ve undoubtedly seen already) with the one on the right being a recently released image of Charon. Neither of these images are the sharpest available, indeed for both Pluto and Charon we have images with up to 10 times the resolution streaming back to us right now, but they are already proving to be fruitful grounds for science. Indeed these two images have already given us insights into other celestial bodies within our solar system. Of course the most interesting thing about these pictures is what they reveal about Pluto and Charon themselves and the insights are many.
The biggest surprise is just how “young” the surfaces of both Pluto and Charon are, devoid of the impact craters that are commonplace on celestial bodies that lack an atmosphere. What this means is that both Pluto’s and Charon’s surfaces have been geologically active in the recent past, on the order of some 100 million years ago or less. There’s even a chance that their surfaces are geologically active today. If they are geologically active today it means that our current theories about the mechanism for this happening aren’t complete and there’s another way for a planet’s surface to refresh themselves.
You see current thinking is that for an icy moon or planet to be able to churn its surface over on a regular basis an outside force has to be acting on them. This is based on the current set of icy moons that orbit around our two gas giants, their giant gravitational fields bending and warping their surfaces as they orbit. However neither Charon nor Pluto has the required mass to induces stresses of that magnitude however their surfaces are still as geologically young as any of the other ice moons. So there must be another mechanism in action here, one that allows even small icy planets and moons to refresh their surfaces on a continual basis. As to what this mechanism is we are not sure but in the coming months I’m sure the scientists at NASA will have some amazing theories about how it works.
The most striking feature of Pluto is the heart which has been tentatively dubbed Tombaugh Regio for Pluto’s discoverer. It consists of 2 different lobes with the one on the left being noticeably smoother than the one on the right. It is currently being theorized that the one on the left is a giant impact crater that was then filled up with nitrogen snow (Pluto’s surface is 98% frozen nitrogen). Considering the resolution of the images we’ll have access too soon I’m sure there will be more than info to figure out the heart’s origin and any other surprising things about Pluto’s surface.
Charon on the other hand appears to be littered with giant canyons, many of them several miles tall. It’s possible that whatever is responsible for the young surface of Charon is also responsible for these giant canyons, something we’ll have to wait for the high resolution images to figure out. Also of note is the giant dark patch on Charon’s polar region which is thought to be a thin deposit of dark material with a sharp geological feature underneath it. As to what that is exactly we’re not sure but the next few months will likely reveal its secrets to us.
These two images alone are incredible, showing us worlds that were simply blurs of different coloured light for almost a century. We most certainly don’t have the full picture yet, the data that New Horizons has will take months to get back to us, but they’ve already provided valuable insight into Pluto, Charon and the solar system in which we live. I can’t wait to see what else we discover as it’s bound to shake up our understanding of the universe once again.
There are numerous risks that spacecraft face when traversing the deep black of space. Since we’ve sent many probes to many locations most of these risks are well known and thus we’ve built systems to accommodate them. Most craft carry with them fully redundant main systems, ensuring that if the main one fails that the backup can carry on the task that the probe was designed to do. The systems themselves are also built to withstand the torturous conditions that space throws at them, ensuring that even a single piece of hardware has a pretty good chance of surviving its journey. However sometimes even all that engineering can’t account for what happens out there and yesterday that happened to New Horizons.
New Horizons is a mission led by NASA which will be the first robotic probe to make a close approach to Pluto. Its primary mission is to capture the most detailed view of Pluto yet, generating vast amounts of data about our most diminutive dwarf planet. Unlike many similar missions though New Horizons won’t be entering Pluto’s orbit, instead it will capture as much data as it can as it whips by Pluto at a blistering 17 km/s. Then it will set its sights on one of the numerous Kuiper Belt objects where it will do the same. This mission has been a long time in the making launching in early 2006 and is scheduled to “arrive” at pluto in the next 10 days.
However, just yesterday, the craft entered safe mode.
What caused this to happen is not yet known however one good piece of news is that the craft is still contactable and operating within expected parameters for an event of this nature. Essentially the primary computer sensed a fault and, as it is programmed to do in this situation, switched over to the backup system and put the probe into safe mode. Whilst NASA engineers have received some information as to what the fault might be they have opted to do further diagnostics before switching the probe back onto its primary systems. This means that science activities that were scheduled for the next few days will likely be delayed whilst these troubleshooting process occur. Thankfully there were only a few images scheduled to be taken and there should be ample time to get the probe running before its closest approach to Pluto.
The potential causes behind an event of this nature are numerous but since the probe is acting as expected in such a situation it is most likely recoverable. My gut feeling is that it might have been a cosmic ray flipping a bit, something which the processors that probes like New Horizons are designed to detect. As we get more data trickled back down (it takes 9 hours for signals to reach New Horizons) we’ll know for sure what caused the problem and what the time frame will be to recover.
Events like this aren’t uncommon, nor are they unexpected, but having one this close to the mission’s ultimate goal, especially after the long wait to get there, is sure to be causing some heartache for the engineers at NASA. New Horizons will only have a very limited opportunity to do the high resolution mapping that it was built to do and events like these just up the pressure on everyone to make sure that the craft delivers as expected. I have every confidence that the team at NASA will get everything in order in no time at all however I’m sure there’s going to be some late nights for them in the next few days.
Godspeed, New Horizons.