Possible Pluto Features Sighted
The news from the New Horizons mission just keeps getting better. The latest images, combined into an animation, show what might be a polar cap on the dwarf planet. It’s the best picture yet of this distant, tiny world. The good news is, as the spacecraft gets closer, the images are just going to get better!
You might wonder how a spacecraft traveling at 14.57 kilometers per second (relative to the Sun), now more than 31.86 astronomical units (that’s nearly 32 times the distance between Earth and the Sun), can send back increasingly better images? It starts with a camera called LORRI, which stands for Long Range Reconnaissance Imager. It’s a small, but powerful instrument, weighing less than 20 pounds and using up less than six watts of electricity. The “guts” of the instrument is a 8.2-inch telescope aperture that focuses visible light onto a CCD. Think of it as a digital camera attached to a telescope. It’s quite small, but powerful and is built to withstand the cold, radiation-filled vacuum of interplanetary space. All of its data are collected on board, and then sent back to Earth via an X-band communications system that includes several antennas. They communicate with the Deep Space Network, which then relays the data to the waiting team members. You can actually see when New Horizons is communicating with Earth at DSN Now.
As New Horizons gets closer to Pluto, its images will improve dramatically. Already, it has shown us that Pluto is a world with surface features. Now, we just have to wait to see what those features are. Starting in mid-May, the images will start to be better than Hubble quality resolution, and that’s when things will really start to get exciting. At flyby, LORRI will be providing looks at the surface that will resolve features only 50 meters (about 150 feet) across. That means we’ll be able to see things such as craters, cliffs, chasms, whatever it is that is making Pluto’s surface look alternately bright, dark, and interesting.
I was listening to the New Horizons team talk about these latest images via telecon yesterday and could really hear the excitement in their voices. My friend Alan Stern (the PI for the mission) whom I’ve been talking with quite a bit in these last few months’ run-up to the flyby, summarized the situation for all the listeners. “After traveling more than nine years through space, it’s stunning to see Pluto, literally a dot of light as seen from Earth, becoming a real place right before our eyes,” he said Alan Stern. “These incredible images are the first in which we can begin to see detail on Pluto, and they are already showing us that Pluto has a complex surface.”
At closest approach, the spacecraft will be about 12,500 kilometers above the surface of Pluto, and that will really give LORRI and the other New Horizons instruments something to show us. So, stay tuned, as they say.
Pluto huggers everywhere: our time is coming!