- Jadeite Found in the Chelyabinsk Object
- Phobos: the Groovy Moon of Mars
- Kepler's Second Light: A New Mission
Knowledge and Dominion
(From ESA/Hubble, via Wikimedia Commons, used w/o permission.)
"Today I would like to highlight another gift of the Holy Spirit: the gift of knowledge. When we speak of knowledge, we immediately think of man's capacity to learn more and more about the reality that surrounds him and to discover the laws that regulate nature and the universe. The knowledge that comes from the Holy Spirit, however, is not limited to human knowledge; it is a special gift, which leads us to grasp, through creation, the greatness and love of God and his profound relationship with every creature...."We live in a beautiful, good, ordered universe: surrounded by wonders which had remained unknown until recent years; and almost certainly many more which we will, in time, discover.
(Pope Francis, General Audience. (May 21, 2014))
God's attitude toward the universe is summed up in "God saw how good it was:" and, after we were created, "very good."
"God looked at everything he had made, and he found it very good. Evening came, and morning followed - the sixth day."We have "dominion" over the visible world: but we're not, as Pope Francis pointed out last week, masters of creation. Our position is more that of stewards.
(Genesis 1:31)
As stewards, we're expected to study the universe, learn how it works, and develop tools that help us use and manage resources for ourselves, and for all generations to come. (Catechism of the Catholic Church, 337-349, 355, 2292-2296, 2415, 2415-2418)
"Creation Never Forgives"
(From Howard Morland, Rocky Kolberg; via Wikimedia Commons; used w/o permission.)
(Mushroom cloud from the 1980 Mount Saint Helens eruption, 40 miles wide and 15 miles high at this point.)
Our world is beautiful, but it isn't entirely safe.
"...Custody of creation is precisely custody of God's gift and it is saying to God: 'thank you, I am the guardian of creation so as to make it progress, never to destroy your gift'. This must be our attitude to creation: guard it for if we destroy creation, creation will destroy us! Don't forget that. Once I was in the countryside and I heard a saying from a simple person who had a great love for flowers and took care of them. He said to me: 'We must take care of the beautiful things that God has given us! Creation is ours so that we can receive good things from it; not exploit it, to protect it. God forgives always, we men forgive sometimes, but creation never forgives and if you don't care for it, it will destroy you'...."Happily, we are learning that creation is ours only in the sense that we are custodians: able to mold its substance and control an increasing range of its processes. And we're learning that being stupid or greedy is not safe: we have become too powerful.
(Pope Francis, General Audience. (May 21, 2014))
Seeking God, Studying God's Creation
We're supposed to seek, know, and love God. (Catechism, 1)Since God created, and is creating, everything, we can learn something about God by studying what God created. (Catechism of the Catholic Church, 31-36, 268, 282-289, 301)
I don't need to be curious about God's creation in order to seek God: but I think deliberately ignoring my Lord's handiwork would be an odd way of showing respect.
I think thoughtful study of this astounding universe is a good way to learn about the God who is creating it.
"...God's fatherly care makes us see creation in a new way and its astounding beauty offers an elegant sign in which we can catch a glimpse of his love. With these sentiments Francis of Assisi contemplated creation and lifted his praise to God, the ultimate source of all beauty...."There's more to God than what we'll find in the physical world, though, and that's another topic. (Catechism, 37-38)
(Pope John Paul II General Audience (May 2, 2012))
"Of old you laid the earth's foundations; the heavens are the work of your hands.
"They perish, but you remain; they all wear out like a garment; Like clothing you change them and they are changed,
"but you are the same, your years have no end. "
(Psalms102:26-28)
More:
- General Audience
Pope Francis (May 21, 2014)
(From w2.vatican.va/content/francesco/en/audiences/2014/documents/papa-francesco_20140521_udienza-generale.html (May 24, 2014)) - General Audience
Pope John Paul II (May 2, 2012)
(From www.vatican.va/holy_father/john_paul_ii/audiences/2001/documents/hf_jp-ii_aud_20010502_en.html (May 28, 2014))
- "Front Row With Francis: The Gift of Knowledge"
Allison Gingras, Catechesis, Featured, Learn & Live the Faith, The Shepherd's Voice, Catholic Lane (May 23, 2014)
Using Our Brains
We live in a beautiful, abundant, dangerous world. Folks can, and have, worshiped, pillaged, and feared it: generally not at the same time. Those are bad ideas.Acting as if any creature is divine is called idolatry. It's wrong, whether a person worships 'idols of silver or gold,' puts money before anything or anyone else, or sees the family as more important that God. It's not that statues, money, or family are bad: it's a matter of priorities. (Catechism, 2112-2114)
Fearing nature doesn't make sense, any more than it would make sense for a shop foreman to be afraid of a drill press. We're expected to use our brains, of course. Physical health is a precious gift from God, one we're expected to take care of: within reason. (Catechism, 2288-2291)
We're expected to use nature: wisely, remembering that we work for ourselves, our neighbors, for all those who will come after us, and for God. not only for ourselves. We're also expected to study this world and develop new tools. Using science and technology is part of being human. (Catechism, 2292-2296, 2401-2418, 2456)
1. Jadeite Found in the Chelyabinsk Object
(Frame from a video, from Reuters/Spetszakaz; used w/o permission.)
("The trail of a falling object is seen above a residential apartment block in the Urals city of Chelyabinsk, in this still image taken from video shot on February 15, 2013."
(Reuters))
"Chelyabinsk asteroid crashed in space before hitting Earth: scientists"Reuters said "...the Chelyabinsk asteroid caused the second most powerful explosion in recorded history...." That's not entirely accurate.
Irene Klotz, Reuters (May 23, 2014)
"An asteroid that exploded last year over Chelyabinsk, Russia, leaving more than 1,000 people injured by flying glass and debris, collided with another asteroid before hitting Earth, new research by scientists shows.
"Analysis of a mineral called jadeite that was embedded in fragments recovered after the explosion show that the asteroid's parent body struck a larger asteroid at a relative speed of some 3,000 mph (4,800 kph).
" 'This impact might have separated the Chelyabinsk asteroid from its parent body and delivered it to the Earth,' lead researcher Shin Ozawa, with the University of Tohoku in Japan, wrote in a paper published this week in the journal Scientific Reports.
"The discovery is expected to give scientists more insight into how an asteroid may end up on a collision course with Earth. Scientists suspect the collision happened about 290 million years ago...."
The Chelayabinsk explosion does come in second after the blast over the Podkamennaya Tunguska River in Siberia back in 1908: that's the biggest explosion caused by incoming debris since we started keeping records. The biggest we know about, anyway. The Tunguska event most likely released energy equivalent to somewhere between 3 and 30 megatons of TNT.
However, the Tsar Bomba fusion bomb, tested in 1961, had a yield of 50 to 58 megatons of TNT. Krakatoa went off with a force of 200 megatons of TNT in 1883, and that explosion was dwarfed by what happened in the South Aegean around the time Hyksos like Sakir-Har were running Egypt.
Thera exploded 3,600 years ago, give or take a few centuries. Folks were keeping records then, but the Minoans, who were closest to ground zero, stopped keeping records right around the time of the explosion. Their civilization went out of business abruptly, too.
We think the Thera explosion blew out about four times as much rock and ash as Krakatoa, the Minoans capital city was on the side of Crete facing Thera, and that's yet another topic.
"A Unique Sample:" and Applying Occam's Razor to 1908 Accounts
(From Shin Ozawa and others; via Scientific Reports, Nature; used w/o permission.)
("(a) The host-rock showing an equilibrated chondrite texture. (b) A shock-melt vein cutting through the host-rock. The two white dotted lines represent the boundaries between them. (c) Coarse-grained fragments and fine-grained matrix in a shock-melt vein. (d) Enlarged view of the area shown by the white rectangular in (c). Needle-like and skeletal-rhombic crystals of jadeite occur with feldspathic glass. Ol = olivine, En = enstatite, Di = diopside, Fsp = albitic feldspar, Me = Fe–Ni metal, Tro = troilite, Chr = chromite, SMV = shock-melt vein, Mtx = matrix of shock-melt vein, Jd = jadeite, Gl = feldspathic glass."
(Shin Ozawa and others))
"Jadeite in Chelyabinsk meteorite and the nature of an impact event on its parent body"As the article says, the "Chelyabinsk meteorite is a unique sample: it is fragments of an NEO actually hit the Earth and its trajectory was well-recorded."
Shin Ozawa, Masaaki Miyahara, et al; Scientific Reports, Nature (May 22, 2014)
"The Chelyabinsk asteroid impact is the second largest asteroid airburst in our recorded history. To prepare for a potential threat from asteroid impacts, it is important to understand the nature and formational history of Near-Earth Objects (NEOs) like Chelyabinsk asteroid. In orbital evolution of an asteroid, collision with other asteroids is a key process. Here, we show the existence of a high-pressure mineral jadeite in shock-melt veins of Chelyabinsk meteorite. Based on the mineral assemblage and calculated solidification time of the shock-melt veins, the equilibrium shock pressure and its duration were estimated to be at least 3–12 GPa and longer than 70 ms, respectively. This suggests that an impactor larger than 0.15–0.19 km in diameter collided with the Chelyabinsk parent body at a speed of at least 0.4–1.5 km/s. This impact might have separated the Chelyabinsk asteroid from its parent body and delivered it to the Earth...."
We've got eyewitness accounts for the 1908 event, but they don't give a particularly accurate picture of the object's path. Back in the '70s, someone with a knack for research, and a good imagination, took what folks reported at the time and traced a zigzag path over Siberia.
As I recall, the author speculated that we were looking at the flight path of a crippled spaceship. It makes sense, in a way: the Space Shuttle ran a sort of stratospheric slalom course while slowing from orbital velocity to subsonic landing speed. In the author's scenario, something went wrong. The pilot, realizing that his/her/its own death was certain, diverted it at the last moment from more-populated parts of Eurasia.
I think that explanation for the Tunguska event would make a good story. I also think that Occam's Razor strongly suggests that we're looking at another example for taking eyewitness testimony with a grain of salt.
In contrast, we have eyewitness testimony for the 2013 event that's backed up by multiple videos and data from a global network of sensors.
Aside from the 'pure science' angle, learning more about how a fragment of some asteroid wound up exploding over a city will help us learn how to keep track of our neighborhood. Next time, we may be able to give folks a 'heads up' before impact: and, not too long from now, prevent the impact.
Falling Rocks and Yarkovsky Effects
(© Nevit Dilmen, used w/o permission.)
(A Crookes radiometer, or light mill: radiation pressure at work.)
It's not so surprising that debris is still falling from the sky, billions of years after the Solar system formed. Major players, like the planets, are in fairly stable orbits, but as the article put it, "gravitational forces, Yarkovsky effects, or collisions with other bodies" keep rearranging smaller objects.
"Yarkovsky effects" isn't a term you probably hear every day, but you've probably seen a demonstration of Ivan Osipovich Yarkovsky's discovery. A light mill, or Crooks radiometer, spins because photons carry momentum, and push against surfaces they hit.
We don't have many machines powered by light mills, since light doesn't push the vanes very hard: but there's enough force exerted to control the Kepler spacecraft, a topic that comes later in this post.
More:
- "Jadeite in Chelyabinsk meteorite and the nature of an impact event on its parent body"
Shin Ozawa, Masaaki Miyahara, Eiji Ohtani, Olga N. Koroleva, Yoshinori Ito, Konstantin D. Litasov, Nikolay P. Pokhilenko; Scientific Reports, Nature (Received January 8, 2014; Accepted May 2, 2014; Published May 22, 2014)
2. Phobos: the Groovy Moon of Mars
(From NASA/JPL/University of Arizona, via Space.com, used w/o permission.)
(Phobos, the larger moon of Mars. Colors are exaggerated in this image.)
"How the Mars Moon Phobos Got Its Grooves"Scientists took new data and images from the European Space Agency's Mars Express orbiter, and mapped the Martian moon's groves with more detail than before.
Joseph Castro, Space.com (May 21, 2014)
"Billions of years ago, Mars suffered from numerous big impacts, and the resulting backwash ultimately scarred the surface of Phobos, one of the Red Planet's two tiny moons, researchers say.
"In 1976, images from NASA's Viking orbiter revealed that the surface of Phobos is covered in numerous parallel, channel-like grooves. Over the years, researchers have come up with many hypotheses to explain the odd features, but the origin of the satellite's grooves are still heavily debated today.
"In the new study, a pair of researchers reviewed the evidence for the major hypotheses and concluded that only one holds water: The grooves are chains of secondary impacts, the landing sites of material blasted to the Mars moon by impacts on the Red Planet. [Moons of Mars: Amazing Photos of Phobos and Deimos]..."
They found that debris thrown up from known impact events on Mars was more than enough to account for the grooves: by about two orders of magnitude.
"...'Everything fits in with this hypothesis,' said John Murray, a planetary scientist at Open University in the U.K., and lead author of the new study, which was published in April in the journal Planetary and Space Science. 'We can even trace the ejecta that produced the grooves back to [source areas] on Mars.'..."The grooves range from 76 to 1,558 feet wide, and from a mile to 18.5 miles long. The only part of Phobos that's not grooved is a patch on the side facing away from Mars.
(Joseph Castro, Space.com)
Although some scientist thought the grooves might be fracture lines, most figured they came from stuff thrown out from impacts: on Phobos, or Mars. What Murray's team came up with isn't so much a new idea, as fine-tuning a widely-accepted one.
3. Kepler's Second Light: A New Mission
(From NASA Ames/W. Stenzel, used w/o permission.)
(If positioned correctly, pressure from sunlight will balance the spacecraft, holding it steady for observing sessions. (See full-size illustration at "Kepler's Second Light: How K2 Will Work.))
Kepler Mission Manager Update: K2 Has Been Approved!"I'm glad to hear that the Kepler spacecraft can be used for scientific research again. It's been down to two of its four reaction wheels since May 11, 2013. That wasn't enough for the extremely steady 'aim' its original planet-hunting mission required.
Ames Research Center, NASA, press release (May 15,2014)
"See full Mission Manager Update.
"Excerpt: The team received good news from NASA HQ — the K2 mission, the two-wheel operation mode of the Kepler spacecraft observing in the ecliptic, has been approved based on a recommendation from the agency's 2014 Senior Review of its operating missions.
"The approval provides two years of funding for the K2 mission to continue exoplanet discovery, and introduces new scientific observation opportunities to observe notable star clusters, young and old stars, active galaxies and supernovae. The 2014 Senior Review report is available at http://science.nasa.gov/astrophysics/documents.
"K2 will observe target fields along the ecliptic plane, the orbital path of planets in our solar system also know as the zodiac, for approximately 75-day campaigns."
"To learn more about the K2 mission visit the Kepler Science Center website."
The good news is that there's more than one way to point a spacecraft.
Reaction wheels are a sort of flywheel that use inertia to move a spacecraft: or hold it in one position. Spacecraft like the Apollo and Vostok modules, used thrusters: comparatively low-thrust rocket engines. Gravity-gradient stabilization works, too, but the K2 mission will use a sort of solar sail.
Light, electromagnetic radiation, acts like waves and particles: depending on what aspect we're paying attention to. In their aspect as particles, photons, tiny bits of light, carry momentum.
Gadgets like a Crookes radiometer, or light mill, work because photons 'push' against surfaces they hit: like lots of BB pellets hitting a cardboard sheet.
Mission planners found a way for the Kepler spacecraft to fold its solar panels into something like a mansard roof: giving the robot observatory good-enough attitude control for its new mission. Just as important, they wangled funding for the K2 mission.
I'm looking forward to seeing what they discover about the birth of star and planetary systems, stellar structure, and the universe beyond our galaxy. Sure, their field of view is limited to the ecliptic: but there's a lot of 'universe' in that direction.
Related posts:
- Using our brains
- "Lowering Costs on the Earth-to-Orbit Run, Preparing for Incoming Asteroids"
(May 2, 2014)
Particularly - "Tunguska and Chelyabinsk Airbursts: Risk, Rocks, and Readiness"
(November 8, 2013)
Particularly - "Asteroids, Comets, and Doing Our Job"
(September 29, 2013) - "Love, Technology, and Being Human"
(October 6, 2013) - "Tornadoes, Trusting God, and Planning Ahead"
(May 22, 2013)
- "Lowering Costs on the Earth-to-Orbit Run, Preparing for Incoming Asteroids"
- The big picture
- "Gravity Waves: Finding Ripples From the Big Bang"
(March 21, 2014) - "Dust and Fomalhaut: Learning that There's More to Learn"
(December 27, 2013) - "Getting a Grip about Genesis, Gamma Ray Bursts, and (Maybe) a Multiverse"
(May 30, 2013) - "Seeking Truth, Accepting Vastness"
(April 2, 2013) - " '...The Man With the X-Ray Eyes,' the Tuskegee Experiment, and Seeking God"
(February 10, 2013)
Particularly
- "Gravity Waves: Finding Ripples From the Big Bang"
1 comment:
Wrong word: "billions of years over the Solar system formed."
Left over place holder: "asdfasdf"
Extra or missing parenthesis: "(If positioned correctly, pressure from sunlight will balance the spacecraft, holding it steady for observing sessions. (See full-size illustration at "Kepler's Second Light: How K2 Will Work.)"
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