New Horizons has started sending back data from its Pluto flyby on July 14, 2015.Pluto and Charon don't have nearly as many craters as scientists expected. One patch, at least, seems to be very new, on the cosmic time scale. Something, maybe Pluto's equivalent of volcanic eruptions, resurfaced that terrain in the last 100,000,000 years.
There's something odd about Charon's north polar region, too. Interesting, anyway.
- Pluto, Up Close: Mountains and Crater-Free Terrain
- Charon: A Chasm, and More Apparently Crater-Free Terrain
- Meanwhile, Back on Earth
- Engineering Data and Human Interest
- Heading for the Hills (Cloud, That is)
New Horizons: Status Updates
(From NASA/APL/Southwest Research Institute, used w/o permission.)
(New Horizons position at 1700 UTC/1200 Central Daylight Time. (CDT) (July 16, 2015))
That diagram shows New Horizons' position at 1700 UTC, yesterday.
If you check the NASA/APL/Southwest Research Institute website's Current Position page for New Horizons, you'll see that the spacecraft is a tad farther from Pluto than it was Thursday. Not much, though. The Solar System is a big place.
I talked about UTC, abbreviations, and a linguistic compromise, last week. Basically, UTC is Earth time — a global standard that's kept to within about a second of time as measured by our star's position in the sky, at a point on an island off the European coast. (July 10, 2015)
This is a blog, not a news service, so I don't always have the very latest news. Particularly when something like the New Horizons Pluto flyby is involved. These folks have been updating fairly often, if you're looking for current information:
- New Horizons
Wikipedia - New Horizons
NASA - New Horizons
The Johns Hopkins University Applied Physics Laboratory
As usual, I'll explain why I'm not surprised that New Horizons didn't smash into the dome of heaven: later. Also why curiosity and thinking aren't sins.
First, though, some equally-boring stuff about Eris, Pluto, Makemake, Haumea, Sedna, Quaoar, Orcus; and my personal favorite: Vanth.
Great Places to Visit
Oddly enough, although I've mentioned how scientists have relabeled things like Pluto and Ceres, I don't seem to have talked about it all that much. (July 10, 2015; )
Where was I? Eris, Vanth, labels for Pluto. Right.
Most of the old Roman deities had counterparts in other pantheons: like Venus, Aphrodite, and Ishtar/Inanna. I suspect that Hercules: The Legendary Journeys's depiction of Aphrodite as apparently-ditsy is closer to how the ancients saw her, than the dead-serious post-Renaissance approach. And I'm veering off-topic.
Wikipedia's Vanth page calls her "a female demon in the Etruscan underworld." and says that she doesn't quite have a Greek counterpart: unless it's the Erinyes, and they weren't quite so benevolent. I'd say that "demon" is overstating it. Sure, Vanth shows up where there's been slaughter and/or murder; but that's because her job is guiding the dead to their next stop.That's probably why the only known satellite of 90482 Orcus is called Vanth. 90482 Orcus's obit, like Pluto's, is in a 2:3 resonance with Neptune, circling the sun twice for every three of Neptune's circuits. Orcus is closest to our sun when Pluto is farthest, and vice versa, so it's occasionally called the anti-Pluto.
We didn't know Eris, Orcus, and all, existed when Tombaugh discovered Pluto in 1930. I'll get back to that.
Since then, we've discovered thousands of smaller objects orbiting our star: and have a great deal left to learn about them.
(From WilyD at English Wikipedia, used w/o permission.)
(Known positions of objects in the outer Solar System within 60 astronomical units (AU) from the Sun on January 1, 2015.)
"Truth Cannot Contradict Truth" — or — Thinking is Not a Sin
(From Wiley Miller, via GoComics.com, used w/o permission.)
Gags like Non Sequitur's "Biblical extinction theory" work because some Christians insist that God must conform to a long-dead Calvinist's ideas. (January 9, 2015; October 10, 2014)
I take the Bible seriously: but I also know that an American didn't write it. That's why I don't think our sun goes around Earth, even though Joshua 10:12-13 seems to say otherwise: from a literalist's viewpoint.
Interestingly, despite what Job 9:6-7 says: I've yet to have an earnest Christian tell me Earth is flat. (June 14, 2015)
I think the universe is billions, not thousands, of years old; Earth isn't flat; Adam and Eve weren't German; poetry isn't science; and thinking is not a sin. (November 21, 2014)
I could be a Christian, and a Catholic, and sincerely believe that the universe is only a few thousand years old, and not much wider than the land I've visited. But that level of ignorance is not required — or encouraged.We've learned quite a bit in the two dozen or so centuries since Mesoptamian culture provided poetic imagery we read in the Old Testament. I'm quite sure that we have a great deal left to learn about this universe.
God gave us brains, and a thirst for knowledge. This is okay. We can learn something of God by studying God's creation. (Catechism, 282-289, 299, 301)
Putting knowledge, or anything else, in God's place is a really bad idea: and very much against the rules. (Catechism, 2113)
But seeking knowledge, studying this universe and developing new tools: these are part of being human. (Catechism, 2292-2295)
I think Einstein had a point, when he opined that God doesn't throw dice:
"Die Quantenmechanik ist sehr achtung-gebietend. Aber eine innere Stimme sagt mir, daß das doch nicht der wahre Jakob ist. Die Theorie liefert viel, aber dem Geheimnis des Alten bringt sie uns kaum näher. Jedenfalls bin ich überzeugt, daß der nicht würfelt."However, I don't see that what we've been learning about quantum mechanics conflicts with my belief that God creates a good, ordered, and beautiful world. (Catechism, 295, 299, 301)
"Quantum mechanics is certainly imposing. But an inner voice tells me that it is not yet the real thing. The theory says a lot, but does not really bring us any closer to the secret of the 'old one.' I, at any rate, am convinced that He does not throw dice."(Letter from Albert Einstein to Max Born (December 4, 1926); The Born-Einstein Letters (translated by Irene Born); Walker and Company, New York, 1971; ISBN 0-8027-0326-7)
We're learning that there's more to reality than classical Newtonian physics: and probably can't predict exactly what the universe will be like in the far future, since we can't precisely measure the position and energy of every particle. That's also okay
My faith doesn't require that I believe we can know everything: just that the universe follows rational, knowable, physical laws. I've discussed quantum mechanics, phlogiston, and unscrewing the inscrutable, before. (April 10, 2015; September 26, 2014)
Bottom line? Fearing knowledge is irrational. As Leo XIII wrote, "truth cannot contradict truth." (Catechism, 159, 214-217; "Providentissimus Deus")
Like I've said before: honest research cannot threaten informed faith.
"...methodical research in all branches of knowledge, provided it is carried out in a truly scientific manner and does not override moral laws, can never conflict with the faith, because the things of the world and the things of faith derive from the same God...."
(Catechism, 159)
1. Pluto, Up Close: Mountains and Crater-Free Terrain
(From NASA, via BBC News, used w/o permission.)
("A new picture of Pluto's surface shows evidence of active geology and mountains comparable to the Rockies"
(BBC News))
"New Horizons: Nasa releases historic Pluto close-up images"
Paul Rincon, BBC News (July 15, 2015)
"Nasa has presented the first images acquired by the New Horizons probe during its historic flyby of Pluto.
"Chief scientist Alan Stern said the new images showed evidence of geological activity and mountains in the Pluto system.
"The team has also named the prominent heart-shaped region on Pluto after the world's discoverer Clyde Tombaugh....
"...Mission scientist John Spencer told journalists that one image of Pluto's surface showed a terrain that had been resurfaced by some geological process - such as volcanism - in the last 100 million years.
" 'We have not found a single impact crater on this image. This means it must be a very young surface,' he said.
"This active geology needs some source of heat. This has only been seen on icy moons, where it can be explained by 'tidal heating' caused by gravitational interactions with the host planet.
" 'You do not need tidal heating to power geological heating on icy bodies. That's a really important discovery we just made this morning,' said Dr Spencer.
"Mission scientist Cathy Olkin added: 'This exceeds what we came for.'
"This same image shows mountains at the edge of the heart-like region that are up to 11,000ft high and which team members compared to North America's Rocky Mountains...."
I think Dr Spencer's right, about Pluto's crater-free terrain being "a really important discovery." Whether he's right about Pluto's geological heating not coming from tidal heating — that, I'm not so sure about.True, Pluto isn't a satellite of another planet/minor planet/whatever. But Charon, one of Pluto's moons, is about half Pluto's diameter, with roughly 11.6% Pluto's mass.
Earth's moon is roughly a quarter Earth's diameter, with about 1.2% Earth's mass. Pluto-Charon is much closer to being a double planet than Earth-Moon is.
Pluto and Charon orbit each other every 6.387 days. They're gravitationally locked, so that each keeps the same face toward the other.
With that sort of tidal locking, I won't be surprised if someone does the math and shows that Pluto and Charon experience enough tidal heating to explain at least some of their geologically-new terrain.
2. Charon: A Chasm, and More Apparently Crater-Free Terrain
(From NASA-JHUAPL-SwRI , used w/o permission.)
(A compressed image of Charon, from New Horizons: combined with color information from the spacecraft's Ralph telescope.)
"Charon’s Surprising, Youthful and Varied Terrain"New Horizons hasn't sent the uncompressed version of this image yet. Depending on your definitions, the spacecraft is at or approaching the Solar System's borderlands. Light — and radio signals — takes about four and a half hours to reach Earth.
Tricia Talbert, New Horizons, NASA (July 15, 2015)
"Remarkable new details of Pluto’s largest moon Charon are revealed in this image from New Horizons’ Long Range Reconnaissance Imager (LORRI), taken late on July 13, 2015 from a distance of 289,000 miles (466,000 kilometers).
"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...."
New Horizons uses X band microwave frequencies (7.0 to 11.2 gigahertz) for communication. At Pluto's distance, New Horizons sends about one kilobit per second through its 2.1 meter/6 foot 11 inch dish antenna.
Remember that 56K dial-up modem? It handled 56 kilobits/second. New Horizons collected a lot of data during the Pluto flyby, so it'll take over a year to send it all.
New Horizons is in the science phase of its timeline now. It's scheduled to keep sending compressed data, letting us know roughly what it has, for the rest of 2015. It'll be late 2016 before all the full, uncompressed, data gets sent: and probably three years or so to analyze it.
By that time, New Horizons may be near another Kuiper Belt object. I'll get back to that, too.
3. Meanwhile, Back on Earth
(From NASA/Bill Ingalls, used w/o permission.)
("New Horizons Flight Controllers celebrate after they received confirmation from the spacecraft that it had successfully completed the flyby of Pluto, Tuesday, July 14, 2015 in the Mission Operations Center (MOC) of the Johns Hopkins University Applied Physics Laboratory (APL), Laurel, Maryland."
(JPL/APL))
"NASA's New Horizons 'Phones Home' Safe after Pluto Flyby"As news releases go, this one is fairly readable: and included some interesting facts. The gist of it, of course, was "we did it, and we're really happy about that."
The Johns Hopkins University Applied Physics Laboratory, New Horizons, News release (July 14, 2015)
"The call everyone was waiting for is in. NASA’s New Horizons spacecraft phoned home just before 9 p.m. EDT Tuesday to tell the mission team and the world it had accomplished the historic first-ever flyby of Pluto....
"...Pluto is the first Kuiper Belt object visited by a mission from Earth. New Horizons will continue on its adventure deeper into the Kuiper Belt, where thousands of objects hold frozen clues as to how the solar system formed....
"...New Horizons is collecting so much data it will take 16 months to send it all back to Earth...."
Folks in the European Space Operations Centre (ESOC) had about the same reactions as Philae lander touched down on 67P/Churyumov-Gerasimenko, last November. (November 14, 2014)
What struck me most was how young most of the folks in the Mission Operations Center were. Part of that is me: by now, just about everyone under age 30 looks like a kid.
4. Engineering Data and Human Interest
(From NASA/JHU-APL/SWRI, used w/o permission.)
("On Tuesday, the US space agency released the most detailed view of Pluto yet"
(BBC News)
"New Horizons: Spacecraft survives Pluto encounter"The odds were very low — about one in 10,000 — that New Horizons would hit uncharted debris during the Pluto flyby. Still, it must have been a huge relief when the "I'm okay" signal came.
Paul Rincon, BBC News (July 15, 2015)
"A signal received from the New Horizons spacecraft shows that it survived its historic encounter with Pluto.
"Data in its first call home since Tuesday's flyby suggest the spacecraft experienced no upsets as it hurtled past the icy world at 14km/s (31,000mph).
"The signal came through a giant dish in Madrid, Spain - part of a Nasa network of communications antennas.
"The message took four hours 25 minutes to traverse 4.7 billion km of space....
"...The signal received on Wednesday morning contained only engineering data, and was designed to tell controllers whether the flyby sequence had been carried out properly. The first high-resolution pictures from the flyby should be downlinked later on Wednesday...."
The 22-hour radio silence during New Horizons closest approach to Pluto wasn't to increase suspense — although I think that was a byproduct of the decision.
The robot spacecraft was very busy as it traveled past Pluto, Charon, and the other moons. I figure that even if mission planners thought the data systems could handle it, they didn't want another "hiccup," like the one that happened during the July 4th weekend. July 10, 2015)
Another 'human interest' item, at the end of this article: relatives of Pluto's discoverer, Clyde Tombaugh, and James Christy, who discovered Pluto's moon Charon, were at mission control when the signal arrived. (BBC News)
About getting engineering data back first, after the flyby? I think that makes a lot of sense. New Horizons' radioisotope thermoelectric generator should be good for another decade, maybe more.Mission planners would feel pretty silly, if they'd missed a 'gotta fix it now' technical glitch by putting off a routine maintenance check.
Besides, by now the data's either been recorded and is ready for transfer back to Earth — or it isn't. New Horizons can't turn around for another try.
New Horizons is outward bound, moving away from Pluto by more than 13 kilometers/eight miles each second. At that speed, it will eventually pass through the Kuiper belt and whatever lies beyond: joining Voyager 1 and 2, and Pioneer 10 and 11, in the void between stars.
We're keeping pretty good records of their headings, and can predict where they'll be as time passes. A few centuries — or millennia — from now, folks may decide to go looking for these probes. And that's another topic.
More about New Horizons:
- New Horizons
Wikipedia - New Horizons
NASA - New Horizons
The Johns Hopkins University Applied Physics Laboratory - "Overview of the New Horizons
Science Payload"
H. A. Weaver, W. C. Gibson, M. B. Tapley, L. A. Young, S. A. Stern; Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland; Southwest Research Institute, San Antonio, Texas; Southwest Research Institute, Boulder, Colorado
(From ppi.pds.nasa.gov/data/NH-X-SWAP-2-LAUNCH-V2.0/DOCUMENT/payload_ssr.pdf (July 16, 2015))
5. Heading for the Hills (Cloud, That is)
(From NASA/JHU-APL/SWRI, used w/o permission.)
("All manner of objects are now starting to turn up in the Kuiper Belt"
(BBC News))
"Pluto flyby: Meet the 'King of the Kuiper Belt' "That instrument is the VBSDC (Venetia Burney Student Dust Counter) Student Dust Counter, built by University of Colorado Boulder students. (See "The Venetia Burney Student Dust Counter," Laboratory for Atmospheric and Space Physics, University of Colorado Boulder)
Jonathan Amos, BBC News (July 13, 2015)
"Sometimes it is hard to comprehend the size of things in astronomy.
"Just our Solar System, the little corner of the Milky Way in which we live, is vast.
"Venetia Burney, the 11-year-old girl who in 1930 suggested the name 'Pluto' for the newly discovered 'planet', remembered playing games in Oxford's University Parks that would try to convey this scale.
"She and her school chums would hang a two-foot-wide orb on the gates to represent the Sun, and then space out a caraway seed for Mercury and peas to signify Venus and the Earth.
"Neptune was a lump of clay and sited a mile and a quarter from the gates.
" 'And then we were told the nearest star would be in China, and that really stuck with me,' she recalled in a BBC interview.
"Before she died in 2009, Venetia got to see the launch of Nasa's New Horizons probe to Pluto. It's even got an instrument on it that is named after her...."
Each time a dust grain hits one of VBSDC's panels, it generates a little voltage. That data's sent back to Earth: giving scientists the first dust data outside Uranus' orbit. This is a big deal, since the Kuiper belt is (fairly) new territory.
When Tombaugh discovered/identified Pluto in 1930, scientists started wondering what else might be out there.Frederick C. Leonard speculated that Pluto was "first of a series of ultra-Neptunian bodies," Armin Otto Leuschner wrote that Pluto "may be one of many long-period planetary objects yet to be discovered."
And that was just in 1930.
Some Irishman got his two cents in: but a Dutchman, Gerard Kuiper, got his name associated with this particular group of outer Solar System objects. In a 1951 Astrophysics journal article, Kuiper described what we call the Kuiper belt: and said that if it ever existed, its contents would have been scattered into the Oort cloud by now — or maybe thrown out of the Solar system entirely.
A whole lot of names you needn't remember later, David Jewitt and Jane Luu started looking for stuff beyond Uranus and Neptune. That was in 1987. August 30, 1992, they spotted what's now called (15760) 1992 QB1. Later, they discovered (181708) 1993 FW
Don't bother trying to remember all those names, particularly (15760) 1992 QB1 and (181708) 1993 FW. Not on my account, anyway.
On the other hand, maybe I should be miffed that a couple of Dutchmen, Kuiper and Oort, got their names attached to vast regions of the Solar System — while a man born in County Westmeath didn't. But that's close to Dublin, and that's yet another topic. Topics.
We still don't know for sure if there actually is an Oort cloud. It's likely that it does, though. Long-period comets come from somewhere, and their orbits suggest that they fell in from regions where stuff left over from the Solar System's formation still (probably) orbits our star.
My guess is that the Oort cloud will have different names as we learn more. Right now, it looks like there's at least two structures out there. And whatddaya know. One of them already has another name: the Hills cloud, named after Jack G. Hills, who published his calculations in 1981.
New Horizons doesn't have much fuel left, so it can't change course by more than about one degree. There's a good chance, though, that the spacecraft can go past two more Kuiper belt objects before running out of power: and getting too far to signal Earth.
Mission planners have a short list of destinations, and will probably have decided where New Horizons goes next by the end of August.
More, mostly about:
- "Pluto's 'Whale,' Comet 67P's Sinkholes"
(July 10, 2015)
Particularly - "A Hidden Crater, Lava Tubes, and Mercurian Ice"
(March 20, 2015)
Particularly - "Dawn's Arrival at Ceres; Sims and 'Chaos' "
(March 13, 2015)
Particularly - "'Organic,' 'Wow!' — and Double Planets"
(November 28, 2014)
Particularly - "Starships, Dinosaurs, and Long-Distance Service for Mars"
(August 1, 2014)
Particularly
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