The New Pluto
With the recent flyby of Pluto in the history books, it’s time to compare what scientists predicted with what they found.
With the recent flyby of Pluto now in the history books, it’s time to compare what scientists predicted with what they found.
It’s been very fulfilling for senior citizens who watched the birth of the space program in 1957 to see the final leg of space reconnaissance of our solar system. Sure, Pluto has been demoted to a ‘dwarf planet’, but for most old-school students, it was the Ninth Planet—the only one never visited by spacecraft. That all changed on 14 July, 2015 with the phenomenally successful flyby of Pluto and its moons by the New Horizons spacecraft.
We should take this opportunity to thank the many engineers and scientists who took the world along vicariously on this great adventure to the far reaches of our solar system. It took copious amounts of intelligent design to outfit a spacecraft, ‘fly’ it for 9½ years, and operate it with just one shot at success.
Data from the encounter will continue trickling down to earth for months to come, but enough has arrived to take stock of the big news. Interpreting data is very different from obtaining it.
What did they expect to find? And why were they so surprised with the “real” Pluto, its large moon Charon, and the subsequently-discovered small satellites Nix, Styx, Hydra, and Kerberos?
We can measure the ‘surprise effect’ by comparing it to writings from the 1990s. The last great textbook on planetary science, The New Solar System,1 authored by leading planetologists, had a chapter on “Triton, Pluto and Charon” by Dale P. Cruikshank. Triton (the large moon of Neptune) had been visited in 1989 by Voyager 2. Scientists had reason to suspect Pluto might share some of its characteristics, since both were classified as Kuiper Belt objects.
Triton, however, had shocked scientists with its evidence of recent activity and ‘water volcanism’. To account for the activity, they invoked a potential heat source: tidal pulls from Neptune over millions of years (though Triton has a nearly perfect circular orbit now, and is the only large moon that orbits retrograde). At Pluto—except for small interactions with Charon—no such heat source exists.
In 1998, scientists knew of light and dark regions on Pluto from Hubble images. They had detected an atmosphere around Pluto containing nitrogen, methane, carbon dioxide; and some hydrocarbons. They knew about Charon, but were surprised that its surface was quite different than Pluto’s, composed mostly of water ice. Knowing that Pluto had passed perihelion in 1990 and was moving away from the sun, Cruikshank speculated that the atmosphere might collapse within a couple of decades: “Maybe the entire planet will turn uniformly white as the entire, already pitifully thin, atmosphere collapses in a global freeze-out!” Seventeen years into that prediction, as we shall see, the atmosphere remains surprisingly dynamic.
How did Pluto form? Cruikshank cited opinions of theorists who later became lead scientists for New Horizons. Here was the “most likely” scenario:
Alan Stern, William McKinnon, and Jonathan Lunine have proposed that Pluto formed in a near-circular, low-inclination heliocentric orbit, probably beyond Neptune’s position. A great many other icy planetesimals also accreted in the solar nebula beyond Neptune, becoming the original population of the Kuiper Belt. The gravity of Neptune perturbed these bodies as they accumulated, resulting in frequent collisions among them. Eventually Pluto managed to garner considerable mass. Later, the powerful impact of a fairly large planetesimal with Pluto resulted in the formation of Charon. This hypothetical impact may also explain why Pluto’s rotational axis is tipped so extremely.2
Now, thanks to New Horizons, we can see the real Pluto system. And we can hear the reactions of these same scientists after their long wait for ground truth. “Who would have expected this kind of complexity?”3 principal scientist Alan Stern remarked after the first images came in. Pluto’s surface is “every bit as complex as that of Mars,”4 one said. Some commented on how earth-like some surface features appear. And one thing stands out to everyone: Pluto looks young!
National Geographic reported that surface images stunned scientists with evidence of glaciers, geysers, and mountains of ice 3,350 m (11,000 feet) high, rivalling the Rockies.5 The landscape “looks relatively young—so young, in fact, that it suggests the planet is still geologically active.” Large areas devoid of craters are seen, implying recent resurfacing. The geologist for New Horizons remarked, “The discovery of vast, craterless, very young plains on Pluto exceeds all pre-flyby expectations.”6
According to the secular scientists, Pluto has been bombarded7 by other objects in the Kuiper Belt for billions of years. The “most stunning thing” about the initial image of Pluto’s southeast quadrant is that not a single impact crater was found. “This means this is a very young surface,” team member John Spencer said. How young? He guessed it is “less than a hundred million years old, which is a small fraction of the 4-and-a-half billion year age of the solar system” (in fact, 1/45 that time span). Actually, “It might be active right now,” he added. “With no craters, you just can’t put a lower limit on how active it might be.”8
The atmosphere is also young. Scientists measured the escape rate of nitrogen at 500 tons per hour. That’s 500 times the rate at Mars. All of Pluto’s nitrogen should have been depleted eons ago. This is such a problem that scientists propose that comets resupplied the nitrogen, but all the proposed sources together appear inadequate.9
Charon is young, too! It shows signs of resurfacing and sports canyons9 five to ten kilometres (three to six miles) deep. How could this small body, about half the diameter of Pluto, be active? “This was unexpected because many thought that the internal heat sources within Pluto and Charon, leftover from their formation in a giant impact billions of years ago, would have dissipated long ago,” Eric Hand wrote for Science.10 “[O]riginally I thought Charon might be an ancient terrain covered in craters,” Deputy Project Scientist Cathy Olkin said at a press conference11 the day after the encounter. “Many on the team thought that might be the case.” They were wrong.
Dropping the assumption of billions of years resolves these problems. Creationists are pleased, but not surprised, to see young surfaces on the planets, because they trust the Word of God. Jesus Christ, the agent of creation (Hebrews 1:2), said, “Have you not read that He who created them from the beginning made them male and female” (Matthew 19:4), two normal-length days after He made the solar system (Genesis 1:14–27). New Horizons provides evidence that the solar system cannot be billions of years old—and consistent with the Bible’s timeframe of thousands of years.
References and notes
- Beatty, J.K., Petersen, C.C., and Chaikin, A. (Eds.), The New Solar System, 4th edn, Cambridge University Press, 1999. Return to text.
- See Beatty, J.K., ref. 1, p. 295. Return to text.
- Wall, M., Mysterious ice plains spotted on Pluto, space.com, 17 July 2015. Return to text.
- Talbert, T. (Ed.), New Pluto images from NASA’s New Horizons: It’s complicated, nasa.gov, 10 September 2015. Return to text.
- Drake, N., First Pluto flyby pictures are ‘complicated and fascinating’: Pluto’s surface looks young, and its large moon Charon offers a few surprises of its own, news.nationalgeographic.com, 15 July 2015. Return to text.
- Loff, S., (Ed.), Frozen plains in the heart of Pluto’s ‘heart’, nasa.gov, 17 July 2015. Return to text.
- See Drake, N., ref. 5. Return to text.
- Brown, D., NASA Offi ce of Communications, Seeing Pluto in a new light, youtube.com, 15 July 2015. Return to text.
- Wall, M., ref. 3. Return to text.
- Hand, E., Potential geysers spotted on Pluto, Science, 17 July 2015 | doi:10.1126/science.aac8875. Return to text.
- See Brown, D., ref. 8. Return to text.