Why Evolution is True is a blog written by Jerry Coyne, centered on evolution and biology but also dealing with diverse topics like politics, culture, and cats.
An artist’s conception of the flyby (from NASA/JHUAPL/SWRI).
Televised events are ongoing, and as I write this, a briefing is being streamed on NASA TV’s YouTube channel.
Brian May, the astrophysicist, who is a scientific collaborator on the New Horizons project, will be releasing a new song, “New Horizons”, to commemorate the voyage. It will be broadcast just after midnight, New York time, and should be shown on NASA TV. (May is perhaps better known as the guitarist from Queen.)
“Thule” was a place described by the 4th century BC Greek traveler Pytheas as being 6 days’ sail north of Britain, and “Ultima Thule” became a phrase meaning “the furthest place on Earth” (it is also, I have just learned, the name of a planet in Star Trek: DS 9). “Thule”, or some variant thereof, has been given as a name to a variety of places, most notably part of northern Greenland, where there is a US-Canadian-Danish air base. Officially named 2014 MU69, the Kuiper Belt Object’s nickname refers to its having the distinction of being the furthest object in the Solar System to ever be closely observed by man.
Pending a few more black and white images still to be taken, the New Horizons odyssey to Pluto is done. It may still have work to do in the Kuiper Belt, but that has not yet been decided.
— Kimberly Ennico Smith (@kennicosmith) July 19, 2015
They’ve already learned some new things, such as Pluto is geologically active. C.C. Peterson at The Space Writer writes:
In the center left of Pluto’s vast heart-shaped feature – informally named “Tombaugh Regio” – lies a vast, craterless plain that appears to be no more than 100 million years old, and is possibly still being shaped by geologic processes. This frozen region is north of Pluto’s icy mountains and has been informally named Sputnik Planum (Sputnik Plain), after Earth’s first artificial satellite. The surface appears to be divided into irregularly-shaped segments that are ringed by narrow troughs. Features that appear to be groups of mounds and fields of small pits are also visible. The blocky appearance of some features is due to compression of the image.
This fascinating icy plains region — resembling frozen mud cracks on Earth — has been informally named “Sputnik Planum” (Sputnik Plain) after the Earth’s first artificial satellite. It has a broken surface of irregularly-shaped segments, roughly 12 miles (20 kilometers) across, bordered by what appear to be shallow troughs. Some of these troughs have darker material within them, while others are traced by clumps of hills that appear to rise above the surrounding terrain. Elsewhere, the surface appears to be etched by fields of small pits that may have formed by a process called sublimation, in which ice turns directly from solid to gas, just as dry ice does on Earth.
Scientists have two working theories as to how these segments were formed. The irregular shapes may be the result of the contraction of surface materials, similar to what happens when mud dries. Alternatively, they may be a product of convection, similar to wax rising in a lava lamp. On Pluto, convection would occur within a surface layer of frozen carbon monoxide, methane and nitrogen, driven by the scant warmth of Pluto’s interior.
You can view a simulation of the flyover here created from the closest-approach images.
A new close-up image of an equatorial region near the base of Pluto’s bright heart-shaped feature shows a mountain range with peaks jutting as high as 11,000 feet (3,500 meters) above the surface of the icy body.
The mountains on Pluto likely formed no more than 100 million years ago — mere youngsters in a 4.56-billion-year-old solar system. This suggests the close-up region, which covers about one percent of Pluto’s surface, may still be geologically active today.
“This is one of the youngest surfaces we’ve ever seen in the solar system,” said Jeff Moore of the New Horizons Geology, Geophysics and Imaging Team (GGI) at NASA’s Ames Research Center in Moffett Field, California.
A swath of cliffs and troughs stretches about 600 miles (1,000 kilometers) from left to right, suggesting widespread fracturing of Charon’s crust, likely a result of internal processes. At upper right, along the moon’s curving edge, is a canyon estimated to be 4 to 6 miles (7 to 9 kilometers) deep.
Mission scientists are surprised by the apparent lack of craters on Charon. South of the moon’s equator, at the bottom of this image, terrain is lit by the slanting rays of the sun, creating shadows that make it easier to distinguish topography. Even here, however, relatively few craters are visible, indicating a relatively young surface that has been reshaped by geologic activity.
In Charon’s north polar region, a dark marking prominent in New Horizons’ approach images is now seen to have a diffuse boundary, suggesting it is a thin deposit of dark material. Underlying it is a distinct, sharply bounded, angular feature; higher resolution images still to come are expected to shed more light on this enigmatic region.
NASA has handled the publicity for this mission really well, there has been a genuine swell in public interest for space exploration. So much so that there is also an earnest campaign underway (apparently supported by a couple of the mission scientists) to reinstate Pluto as a full planet as opposed to a dwarf planet. I’ve kind of got mixed feelings about this myself. It’s wonderful that so many people are prepared to get passionate about space and planets. I’ve been giddy about them myself since I was a small child, so I get it. But this is a perfect way to dig the ground out from under your own feet the next time any scientist wants to point out that science is not decided by popular vote. (Remember when some eejit in Indiana wanted to change the value of pi by legislation?)
You can sign the petition here, if you want. I’m still not sure if I am going to, because I don’t think this is the right way to promote science literacy. Perhaps I am wrong, and perhaps I am a cranky curmudgeon. Maybe just getting people to be excited about science is the right way to start. After all, all it took for me as a small child was the shiny photographs in Time Life’s glossy coffee table books on space and the planets, I cared nothing for the scientific method then.
As a last note, don’t miss NASA’s hour long documentary The Year of Pluto.
NASA is still waiting on color data from New Horizons, but so far there is a wealth of information received from the epic journey out to the Kuiper Belt.
Charon’s newly-discovered system of chasms, larger than the Grand Canyon on Earth, rotates out of view in New Horizons’ sharpest image yet of the Texas-sized moon. It’s trailed by a large equatorial impact crater that is ringed by bright rays of ejected material. In this latest image, the dark north polar region is displaying new and intriguing patterns. This image was taken on July 12 from a distance of 1.6 million miles (2.5 million kilometers).
There are now some geology features to work with, it’s not known what they are yet.
The spots appear on the side of Pluto that always faces its largest moon, Charon—the face that will be invisible to New Horizons when the spacecraft makes its close flyby the morning of July 14. New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado, describes this image as “the last, best look that anyone will have of Pluto’s far side for decades to come.”
The spots are connected to a dark belt that circles Pluto’s equatorial region. What continues to pique the interest of scientists is their similar size and even spacing. “It’s weird that they’re spaced so regularly,” says New Horizons program scientist Curt Niebur at NASA Headquarters in Washington. Jeff Moore of NASA’s Ames Research Center, Mountain View, California, is equally intrigued. “We can’t tell whether they’re plateaus or plains, or whether they’re brightness variations on a completely smooth surface.”
And here’s the amazing picture from the final approach to Pluto and Charon.
Image credits: NASA/JHUAPL/SWRI
Here’s a video of the team counting down and celebrating.
UPDATE
NASA is doing a Reddit at noon ET , Facebook at 2pm ET & Twitter at 6pm ET “Ask Me Anything” Q&A session.
The first space mission to explore Planet Pluto is now 5 days from target, the last of our solar system’s planets (or not-planets) to be visited. New Horizons will then pass within 12,500km of the surface. The mission hopes to uncover knowledge about its surface and atmosphere. There’s an in depth discussion of what the mission would like to uncover as well as questions about Pluto that are as yet unanswered over on the America Space website.
There is also a competition running to name the mountains on Pluto’s moon Charon, and it appears that they’re going to end up being a character out of Star Wars or Star Trek.
Pluto & Charon seen from Hubble. Image Credit: NASA/JPL-Caltech
Pluto is technically a Dwarf Planet, having been demoted from full planet status in 2006 on the basis that “has not cleared its neighboring region of other objects” according to the International Astronomical Union. Its demotion caused an upset, not least amongst young fans of the solar system who bombarded Neil DeGrasse Tyson with angry letters about it.
Credit: PBS NOVA
He’s apparently since made peace with Pluto, ot at least, that is his story and he’s sticking to it.
Just an FYI: Pluto and I buried the hatchet a long time ago. And we’ve been pals ever since. pic.twitter.com/zPQNymxVUV
