Gravity & Energy

This category of the blog is dedicated to science & technology topics that I think may interest my fellow nerds.

(Note: Original post: 2012. A few updates were made during site reorganization in January, 2021.)

Tracking Movement In the Solar System

For starters, I’ll be posting in the blog regularly under Astronomy & Astrophysics. (In some of these older posts the category is tagged Pixel Gravity.)  To jump straight to those posts, visit the PG Archive–readily accessible in the menu.  For some time now, I’ve been running the social-media support for the program that made the picture you see here.  I’ve been posting about robots, space exploration, astronomy, big steps in physics, and so on.  Sometimes, the space available for a posting on Facebook is too restrictive.   So those kinds of discussions will move here.

What qualifies me to write about this stuff?  Well, I’ve admitted elsewhere that we are a family of hypernerds.  That’s not my term.  It was invented and applied by one of our charming (adult) offspring.  It’s not a misnomer As a family, we are 40% engineers and 60% scientists.

I’m a power systems engineer, which in my case means I’ve made a career out of simulating how power plants and electric and gas networks operate.

My husband is a computational physicist, specializing in solar physics.  Want to know what’s going on inside the sun?  He’s your guy.

Our youngest son is too busy for now, building catapults and robots on his way to a mechanical-engineering degree at UC Santa Barbara. (Update: graduated, with honors. Currently open to job offers.)

After two summer internships in NASA’s astrobiology group, our middle son is working on an honors thesis project on metabolic processes of microbes in deep serpentine wells, attracted by the prospect of doing biology fieldwork in extreme ecosystems right here on planet Earth. (Update: he’s now nearly done with his Ph.D.)

And the oldest escaped from UC Berkeley’s astrophysics program with a degree and a desire to never return to academia.  He built Pixel Gravity instead.

What’s “Pixel Gravity“?  It’s a detailed, graphical astrophysics simulator with real-time controls.  It looks sort of like a game, and it’s fun to play with, but it’s also a serious science tool  As an “n‑body” simulator, it lets users model complex groups of many objects, from the solar system to galaxies.  Most of the other easy-to-use programs available online limit the number of objects or lack physical accuracy, so (for example) relativistic effects on motion near a black hole are not handled properly, if at all.  University researchers have access to extremely-detailed models, but those require supercomputers.  Pixel Gravity provides accurate modeling on personal computers and is priced low so that even students can explore gravity in action.  In addition to Newtonian gravity, Pixel Gravity models the additional effects of atmospheric drag, general relativity, and dark-matter, as well as user-defined forces.  Plus, the software package includes helpful tools for curriculum development such as a tutorial-builder and video-production capability. (Update: Pixel Gravity is at present a retired product–contact us if you’d like a copy to play with.)

So, in short, the topics under this heading are just the kind of things we talk about at our house.  So if you come to dinner, you don’t need to bring a foodie specialty.  But you might scan the latest issue of Scientific American.

You might also like to read:

Drake & Josh at the Kepler ConferenceDrake & Josh at the Kepler Conference

No, this entry has absolutely nothing to do with the old Nickelodeon TV show.  It’s just that while doing my edits on the very few photos I took last night, I found that half of them were titled Drake & Josh 1, Drake & Josh 2a, and Drake & Josh 2b.

No, wait.  Back up.

(Note:  if “Kepler” means nothing to you, go peek at this first:  NASA’s Kepler page.)

Last night was a public session during this week’s Kepler Science Conference at NASA-Ames Research Center.  Frank Drake—does anybody even faintly interested in extraterrestrial intelligence NOT remember the Drake equation?—was the speaker for a ‘sold-out’ evening at the Conference Center.

Drake with a glimpse of Lynette Cook's Art

Frank Drake          (with a glimpse of Lynette Cook’s Galactic Internet)

With the tiniest bit of encouragement, my husband “Clark” had scored a pair of the free tickets offered to the public by the Ames Events Program.  We even managed to arrive early enough to worm our way into decent seats just behind the “reserved for press” row.  Just between you and me, acquiring those seats involved summoning the chutzpah to ask a woman who was clearly saving a seat for her husband if she could shift left or right one seat to make room, either by claiming the aisle seat for her husband or dibsing the middle seats.  She chose the aisle-seat access.  As she moved over, so did the young man next to her, leaving us with one more free seat which was swiftly nabbed by someone in the next wave of arrivals.

So it all works out well.  One more person got a nearly-front seat (without having to ask for favors), we started the evening filled with gratitude, and the college student got to sit with David Morrison—NASA astrobiologist and SETI Institute leader—and his wife.  (Yes, that’s who the tardy husband was.  “Why didn’t you tell me?” I said to Clark.  “Well,” he lamely explained.  “I don’t see him with his wife at the cafeteria.” )  The student had taken Caltrain all the way from San Francisco and then hiked from the train station to Ames.  He was excited to be surrounded by so many astronomers, but instead of being daunted by that, he’d decided to get as many autographs as he could on his printout about the event.  Most people he asked for autographs from also gave him business cards and some asked for his name in return.    His name is Joshua Caltana.

So now you see where that strand is headed.

Meanwhile, there were a fair number of cell-phone photos being requested in the front-row group.  Frank with one Kepler astronomer.  Frank with another.  A photo of someone taking a photo of Frank with someone.  Was it noted that one of the people sitting in the front row a few feet away was Dr. Drake?   Oh, to be an official Press Person.  They really needed a proper camera with a bounce flash in that light.

A free public talk in the heart of Nerd Country is a strong draw, and traffic was backed up at the gate, we heard.  So there was a delaying action.  Kepler staff launched a putatively impromptu quiz game, awarding Kepler memorabilia to audience members who had the correct answers to crucial astro-trivia.  Alas, I was way too slow to raise my hand on the few I knew, Clark was not interested in playing the game, and Joshua’s answer to one question was just close, not correct.  So our Local Group did not win any of the tchotchkes.  Oh, well.  We didn’t come for prizes.  We came to hear “Frank”.

But finally, they tuned up the computer with Drake’s slides and let him speak.  He had a bit of a scratchy throat to cope with, and the Mac was balky about launching the animations on his slides, but he soldiered on with all those rapt faces in attendance.

So yes, I’m going to make you endure a summary of a great talk before looping back to Drake & Josh.  Or you can be lazy and scroll to the end.  Bear with me.  There will be cool links.

Drake does autographs

Drake does autographs (later, later)

So, the talk was entitled “Kepler and Its Impact on the Search for Extraterrestrial Intelligence.”  But Drake put it a little more strongly.  Kepler, he said, is one of the “most important events in the history of science.”   Not only has the Kepler team’s search for habitable planets spotted thousands of planets orbiting stars in the small portion of sky selected for study, their data are useful for sorting through those finds for planets which might fall in the habitable zone.  The sheer impact of numbers is amplified when we realize that Kepler isn’t looking everywhere and that the Kepler results strongly suggest that there are many many more planets out there that the current tools can’t locate just yet.

For one thing, Kepler’s detection technique relies on occultation—spotting a planet passing in front of its star.  Only planets fairly close to a star are likely to be sighted this way, because the farther out a planet’s orbit lies, the more likely that a slight tilt of its orbit relative to our plane of view would make the planet pass ‘above’ or ‘below’ the star—making it invisible to us.  For example, even just at Earth’s orbital distance, 99% of such planets would be missed.

But for now, the numbers are big enough to give us plenty of data to study and inspire us.  Drake’s presentation included a snippet of the Kepler Orrery in which all the planets discovered as of early 2011 dance their way through Kepler’s mission period.  If you’re not too hypnotized by that, you can try Fabryky’s 2012 updated edition.

Kepler results include information about the planets’ orbital distances, and the stars’ characteristics are well-known, so the likelihood of there being planets in their respective habitable zones is becoming accessible.  For instance, with a cooler star, the habitable zone is close.  But what affects the habitable zone other than the star and the orbital distance?  From studying our own solar system, even just our own planet, we know that the characteristics of the planet affect habitability.

The Habitable Zone:  Colorado University

So, then Drake moved into Phase II of his talk, which he later revealed should have its own title

Everything I Ever Needed to Know

I Learned in

Kindergarten   

The Solar System

Aiming for that laugh, he led us on a tour of our own locale.  On Planet Earth, habitability changes markedly if we go up in altitude or down into the ocean.  So the topography and water on a planet affect its habitability.  In the deep atmospheres of the outer planets, it’s been proven that there are altitudes at which temperatures—even so distant from the sun—are about what they are on the Earth’s surface.  He shared an image by Lynette Cook illustrating Carl Sagan’s notion of “floaters” evolving and living in the clouds of Jupiter.   Comb jellies accustomed to the arctic seas of Earth—or alien life evolved to a similar design—would be well-suited to the deep, dark ocean beneath Europa’s insulating icy crust.  Our focus on the traditional Habitable Zone defined by certain distances from each star, based on stellar conditions, means that these alternate conditions for life finally need to get some attention so that the Habitable Zone can be redefined to include these non-Earthly, yet potentially life-supporting situations.   He foresees the narrow band illustrated above being widened to include most of the outer planets…and even those wandering ‘rogue’ planets warmed by nuclear decay.

Next, Drake turned to the conundrum of M-type stars and their planets.  He’s now convinced—thanks to Kepler—that there are likely to be planets around most of these stars as well—and those cool M-types (more familiarly known as Red Dwarfs) are far and away the most common stars.  There are more of them than of all the other star types combined.  Until recently, most astronomers were convinced that a planet anywhere in the narrow old-style Habitable Zone of an M-Type would be so close that it would be tidally locked—with one face permanently facing sunward, dooming the planet to be boiling on one side and frozen on the other.   But those convictions are faltering in the face of new understandings about how orbital eccentricities—such as that of our own planet Mercury—can prevent tidal locking and instead force a planet into a resonance pattern.   (Is this breaking news—did you still think Mercury keeps one face to the sun?  Take a break with Universe Today’s article on resonance.)

Even for a planet that ‘succeeds’ in achieving a tidal lock, atmospheric scientists have decided (provided the planet does have an atmosphere), that mixing by the currents of gas moving over the surface, driven by the heat of a star, would more or less normalize the planet’s temperature, establishing stable conditions in a range of habitation zones.  Drake mused that residents of such a predictable planet would consider it nothing more than “wretched circumstances” to endure life on a rock which rotates constantly and varies its temperature patterns hourly, daily, and seasonally.

Drake never directly brought his famous equation into his talk.  But one critical factor is the length of time that a civilization might be communicating—the likelihood of our finding one another falls if our conversational eras fail to overlap sufficiently.   However, he reported “good news for people who afraid that we have been advertising our presence” and are worried about aliens being “about to invade.”  Our own passive “communication” to the Universe has been dropping off precipitously as our use of technology and energy has shifted.   We used to beam many megawatts of television broadcasts into space.  No more—we’re going with digital, satellite, cable TV now, meaning thousands of times less energy expended accidentally broadcasting to the stellar neighborhood.  Soon, the only signature of our technological civilization to a far-off society could be the lights of our night-lit cities—something we aren’t yet capable of looking for ourselves.  A very patient observer might notice our atmosphere heating up over time and deduce that we have been subjecting our planet to global warming.

Drake enjoys a chat about astronomy

Drake enjoys a chat about SETI

Drake said he is beginning to feel that it may be our moral obligation to start an intentional broadcast, to try to share what we have learned with unknown aliens in the far-off planetary systems.  His reading leads him to believe that altruism is a part of our evolutionary heritage and to hope that evolution elsewhere has instilled enough of that same drive to cooperate so that eventually we may be able to do the one thing that we can do over interstellar distances—talk.

What about the Fermi paradox?  Where are those others?  One audience member was convinced that visitors have been here already, but Drake sadly told him he’d checked out those same stories when he was younger, too, and was disappointed to find they were all dead ends, that the fantastic accomplishments of early civilizations on Earth didn’t rely on helpful aliens but on ordinary humans performing great feats.  Interstellar travel is too expensive, in energy terms, he thinks.  When pressed, Drake’s line is that the reason we haven’t seen alien interstellar travellers is that “the only ones who would try are the dumb ones—and they don’t know how.”

So after the Q&A, there was a little bit of meet-and-greet.  Yes, I got to shake Drake’s hand and tell him I enjoyed the talk and always like it when I hear something new.  He said, “well, I try.”  Our new acquaintance, Joshua, roamed the crowd collecting a few new autographs and working up to saying hello to Drake.  By that time, he was one of the last well-wishers.  Drake was surely pining for dinner (his companions were already talking about food), but he listened to this young student, gave his autograph, and then instead of grabbing his bag and dashing away, he stood up and chatted with him for a few minutes.  Ergo:  Drake & Josh 1, 2a, and 2b:

Drake & Josh 1

Drake & Josh 1

Drake & Josh 2a

Drake & Josh 2a

Drake&Josh 2b

Drake&Josh 2b

 

 

 

 

 

 

 

Coda:  Clark was starved, I was hungry.  So we went in search of dinner.   We randomly selected an open restaurant, placed our orders.  And then Frank Drake and his entourage arrived.  (Well, is 2 people an entourage?  Let’s just say yes.)  So I conclude my report with a mention that Frank Drake finished his long day of Keplering with an omelet plate at Crepevine.  I hope he survived—the portions there are well on the way to having detectable gravitational effects.

 

 

 

 

. . . GO! “All That Was Asked” is out, now!. . . GO! “All That Was Asked” is out, now!

The pre-midnight roll-out

One thing about the global economy…it’s January 31st in some places already. Barnes and Noble has the paper editions as well as the Nook version ready to go.

Meanwhile, Amazon is lagging behind, with just the Kindle version and it still is tagged as “preorder” . . . in the U.S. C’mon Jeff, don’t you want more money for your rocketship project? UPDATE: Amazon is up, in Kindle and Trade Paperback editions.

But you can download it from Amazon’s sites for the UK or India.

And it’s up at Canada’s Biggest Bookstore, !ndigo.

And in Australia at Angus & Robertson.

No problems at Smashwords, either.

And you can use Paper Angel as a home base, plus a place to read the sample or order a signed copy direct from the publisher.

My favorite, though, is the listing on Rakuten-Japan. Though of course it’s on “regular” Rakuten, too (i.e., Kobo).

Monday at BayCon 2013Monday at BayCon 2013

There are fewer options on the final day, and the available time is short, so opportunities for plans to stray from reality are fewer.  We’d expect less divergence…here are the results of our field test:

Time Frame What the Plan was What really happened
Monday morning Sleep in a bit, then go to session on James Bond vs Dr Who, and finally pick up art if I win any auctions.

One of Patricia McCracken's Little Dragons came home with me!  Find your own here http://www.patriciamccracken.com/miniprint.html

One of Patricia McCracken’s Little Dragons came home with me! Find your own here .

Did sleep in.  Fed horses & scooped manure, too.  Didn’t arrive until close to noon.Trekked to the Art Show first to pick up the two pieces I’d bought, but then also discovered my single bid on the dragon-butterfly print was the winning bid.  So paid and went to look for that panel talk.  JB vs DW still ongoing, but after a half-hour I figured I’d had about all I needed on the topic.  So no regrets about turning up so late. 

My next move was to get my art safely into the car, though I did make a detour to make sure there was no boffering available today.  Dang.  Just another panel talk going on in what had been Boffer Central.

 

So I betook myself down to the Gaming Room to buy a coke and eat lunch.  Two older teenagers who had joined in on the dancing last night were there playing some form of D&D.  The one thing I haven’t done at this convention is play games, and it looks like that will have to be another time.  For now, I just have to settle for having spent some time hanging out in the Gaming Room.

Monday afternoon Go to session on “how to build a spaceship.”  Go home!

First firing of the Falcon 9-R advanced prototype rocket. Via Elon Musk on Twitter. Read more: http://www.universetoday.com/102692/spacex-tests-falcon-9-r-advanced-reusable-prototype-rocket/#ixzz2WVt42LYG

First firing of the Falcon 9-R advanced prototype rocket. Via Elon Musk on Twitter.   At least there is a good place to read about the topic I skipped:  start here.

 

MKB's latest novel in the Star Wars universe

MKB’s latest novel in the Star Wars universe

 

 

California Autism Foundation

California Autism Foundation

 

diy

 

 

 

 

 

It was easier to walk to the media tie-in panel from the Gaming Room, so that’s where I went.   I hadn’t actually looked at the list of panelist, so it was a pleasing surprise to see Maya Kaathryn Bohnhoff  there, in her capacity as a leading author in Star Wars novels.  Her panel partner, Kevin Andrew Murphy, works also in gaming tie-ins and had a much more positive spin on the quality of that literature than the board-game guy in yesterday’s panel.  Overall, I gained a much better picture of life as a tie-in fiction author.  And an appreciation for authors who can face intense fans in the middle of a panel.    Btw, about half the people in the audience are people I recognize.So things were winding down, including the dealer’s room.  So I went on up to the closing ceremonies.  In between that and the “hiss and purr” session, there was some dead time.  I poked my head into the Art Room to see how the art auction had wrapped up.  One of the women I remember from dancing last night was clutching the steampunk flamingo.  Turns out it hadn’t had any bids, so the artist had offered it to her at a lesser price in order to avoid hauling it home.  Good for her! 

Next stop:  the Gaming Room, for one last donation to the California Autism Foundation (the beneficiary of the Charity Vending machine) from which I gained a Coke for myself and an accidentally-vended ginger ale which I could donate to one of the nearby volunteers.

 

I was determined to stay for the critique session because I wanted to praise the DIY idea.  The downside was having to sit through a huge laundry list of facility complaints and an equally lengthy recitation of praises for hotel staff.  However, managed to retain my nerve enough to actually participate in the “programming” discussion.

 

After that subject was concluded, I took off for Nob Hill.  Not the SF landmark, the grocery store.  Got home before the guys and even fixed dinner for everyone.  Does tacos count as dinner?

 

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