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Rabu, 29 Mei 2019

SpaceX satellites pose new headache for astronomers - Phys.org

In this screengrab taken from a video shot by Marco Langbroek, a group of SpaceX Starlink satellites passes over Leiden, Netherlands on May 24, 2019

It looked like a scene from a sci-fi blockbuster: an astronomer in the Netherlands captured footage of a train of brightly-lit SpaceX satellites ascending through the night sky this weekend, stunning space enthusiasts across the globe.

But the sight has also provoked an outcry among astronomers who say the constellation, which so far consists of 60 broadband-beaming satellites but could one day grow to as many as 12,000, may threaten our view of the cosmos and deal a blow to scientific discovery.

The launch was tracked around the world and it soon became clear that the satellites were visible to the naked eye: a new headache for researchers who already have to find workarounds to deal with objects cluttering their images of deep space.

"People were making extrapolations that if many of the satellites in these new mega-constellations had that kind of steady brightness, then in 20 years or less, for a good part the night anywhere in the world, the human eye would see more satellites than stars," Bill Keel, an astronomer at the University of Alabama, told AFP.

The satellites' brightness has since diminished as their orientation has stabilized and they have continued their ascent to their final orbit at an altitude of 550 kilometers (340 miles).

But that has not entirely allayed the concerns of scientists, who are worried about what happens next.

Elon Musk's SpaceX is just one of a several companies looking to enter the fledgling space internet sector.

To put that into context, there are currently 2,100 active satellites orbiting our planet, according to the Satellite Industry Association.

If another 12,000 are added by SpaceX alone, "it will be hundreds above the horizon at any given time," Jonathan McDowell of the Harvard Smithsonian Center for Astrophysics told AFP, adding that the problem would be exacerbated at certain times of the year and certain points in the night.

This screengrab taken from the SpaceX webcast transmission on May 23, 2019, shows a SpaceX Falcon 9 rocket with 60 Starlink satelites lifting off from Space Launch Complex 40 (SLC-40) at Cape Canaveral Air Force Station, Florida

"So, it'll certainly be dramatic in the night sky if you're far away from the city and you have a nice, dark area; and it'll definitely cause problems for some kinds of professional astronomical observation."

Musk's puzzling response

The mercurial Musk responded to the debate on Twitter with contradictory messages, pledging to look into ways to reduce the satellites' reflectivity but also saying they would have "0% impact on advancements in astronomy" and that telescopes should be moved into space anyway.

He also argued the work of giving "billions of economically disadvantaged people" high-speed internet access through his network "is the greater good."

Keel said he was happy that Musk had offered to look at ways to reduce the reflectivity of future satellites, but questioned why the issue had not been addressed before.

If optical astronomers are concerned, then their radio astronomy colleagues, who rely on the electromagnetic waves emitted by celestial objects to examine phenomena such as the first image of the black hole discovered last month, are "in near despair," he added.

Satellite operators are notorious for not doing enough to shield their "side emissions," which can interfere with the observation bands that radio astronomers are looking out for.

"There's every reason to join our radio astronomy colleagues in calling for a 'before' response," said Keel.

"It's not just safeguarding our professional interests but, as far as possible, protecting the night sky for humanity."

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Lights in the sky from Elon Musk's new satellite network have stargazers worried

Citation: SpaceX satellites pose new headache for astronomers (2019, May 29) retrieved 29 May 2019 from https://phys.org/news/2019-05-spacex-satellites-pose-headache-astronomers.html

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2019-05-29 07:15:42Z
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Selasa, 28 Mei 2019

SpaceX's internet satellites could be a problem for astronomers - Engadget

Researchers crack an enduring physics enigma - Phys.org

For decades, physicists, engineers and mathematicians have failed to explain a remarkable phenomenon in fluid mechanics: the natural tendency of turbulence in fluids to move from disordered chaos to perfectly parallel patterns of oblique turbulent bands. This transition from a state of chaotic turbulence to a highly structured pattern was observed by many scientists, but never understood.

At EPFL's Emerging Complexity in Physical Systems Laboratory, Tobias Schneider and his team have identified the mechanism that explains this phenomenon. Their findings have been published in Nature Communications.

From chaos to order

The equations used to describe the large variety of phenomena occurring in fluid flows are well known. These equations capture the fundamental laws of physics that govern fluid dynamics, a subject taught to all physics and engineering students from undergraduate level onwards.

But when turbulence comes into play, the solutions to the equations become non-linear, complex and chaotic. This makes it impossible, for example, to predict weather over an extended time horizon. Yet turbulence has a surprising tendency to move from chaos to a highly structured pattern of turbulent and laminar bands. This is a remarkable phenomenon, yet the underlying mechanism remained hidden in the equations until now.

Here's what happens: when a fluid is placed between two parallel plates, each moving in an opposite direction, turbulence is created. At first, the turbulence is chaotic, then it self-organizes to form regular oblique bands, separated by zones of calm (or laminar flows). No obvious mechanism selects the oblique orientation of the bands or determines the wavelength of the periodic pattern.

Credit: Ecole Polytechnique Federale de Lausanne (EPFL)

Concealed in simple equations

Schneider and his team solved the mystery. "As the physicist Richard Feynman predicted, the solution was not to be found in new equations, but rather within the equation that was already available to us," explains Schneider. "Until now, researchers didn't have powerful enough mathematical tools to verify this."

The researchers combined one such tool, known as dynamical systems theory, with existing theories on pattern formation in fluids and advanced numerical simulations. They calculated specific equilibrium solutions for each step of the process, enabling them to explain the transition from the chaotic to the structured state.

"We can now describe the initial instability mechanism that creates the oblique pattern," explains Florian Reetz, the study's lead author. "We have thus solved one of the most fundamental problems in our field. The methods we developed will help clarify the chaotic dynamics of turbulent-laminar patterns in many flow problems. They may one day allow us to better control flows."

An important phenomenon

In fluid mechanics, stripe pattern formation is important because it shows how turbulent and laminar flows are in constant competition with each other to determine the final state of the fluid, i.e., turbulent or laminar. This competition arises whenever turbulence forms, such as when air flows over a car. The turbulence starts in a small area on the car's roof, but then it spreads—because turbulence is stronger than laminar flow in this particular case. The final state is therefore turbulent.

When the stripe pattern forms, it means that the laminar and turbulent flows are equal in strength. However, this is very difficult to observe in nature, outside of the controlled conditions of a laboratory. This fact points to the significance of the EPFL researchers' success in explaining a fundamental property of turbulence. Not only do their findings account for a phenomenon that can be observed in a laboratory, but they could help to better understand and control flow-related phenomena occurring in nature as well.

Explore further

What does turbulence have in common with an epidemic?

More information: Florian Reetz et al. Exact invariant solution reveals the origin of self-organized oblique turbulent-laminar stripes, Nature Communications (2019). DOI: 10.1038/s41467-019-10208-x

Provided by Ecole Polytechnique Federale de Lausanne

Citation: Researchers crack an enduring physics enigma (2019, May 28) retrieved 28 May 2019 from https://phys.org/news/2019-05-physics-enigma.html

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2019-05-28 13:47:33Z
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Ancient supernovae prompted our ancestors to walk upright to avoid forest fires - Daily Mail

How a barrage of lightning strikes triggered by ancient supernovae around EIGHT MILLION years ago could have first prompted human ancestors to walk upright

A supernova is the explosion of a star that has reached the end of its life
This cosmic energy initiated a surge of electrons in our lower atmosphere
Researchers say that this resulted in lightening strikes which caused forest fires
According to the team, the fires caused wide-expanses of open space which meant that ancient hominins didn't need to climb trees leading to their evolution

By Victoria Bell For Mailonline

Published: 14:01 BST, 28 May 2019 | Updated: 14:17 BST, 28 May 2019

Supernovae that bombarded Earth with energy millions of years ago may have resulted in our ancient ancestors learning to walk upright, research suggests.

Electrons from the energy released from the exploding stars triggered a surge in lightning strikes, according to a new study.

These strikes sparked forest fires around the globe, with savannas arising to replace the scorched woodlands.

Prehistoric humans - or proto-humans - lived their lives on all fours in these forests before shifting to two to adapt to the new plains as far back as eight million years ago, experts say,

Exactly why and when our distant ancestors stood upright and started moving around on two feet is still widely debated by scientists.

This study, from the University of Kansas, claims that this was a knock-on effect from the supernovae.

These stars reached the end of their life and their energy reached Earth during the transition from the Pliocene Epoch to the Ice Age.

Scroll down for video

A new paper from a University of Kansas researcher suggests bipedalism arose when ancient supernovae caused lightning that burned Earth's forests and prompted human ancestors to walk upright

Our planet was bombarded with cosmic energy starting as many as eight million years ago, with a peak some 2.6 million years ago.

This initiated an avalanche of electrons in the lower atmosphere. Atmospheric ionisation caused by waves of energy started lightning strikes that resulted in forest fires in northeast Africa.

The destroyed forests were then replaced by wide expanses of mixed woodland and open grassy plains.

This meant that our ancient hominin ancestors didn't need to climb trees and, because of this experts say, human evolution to walking upright on two legs took place.

Lead author Adrian Melott, a professor emeritus of physics & astronomy at the University of Kansas, even before this event,there was already a tendency for hominins to walk on two legs.

'But they were mainly adapted for climbing around in trees. After this conversion to savanna, they would much more often have to walk from one tree to another across the grassland, and so they become better at walking upright.

'They could see over the tops of grass and watch for predators. It's thought this conversion to savanna contributed to bipedalism as it became more and more dominant in human ancestors.'

Based on a 'telltale' layer of iron-60 deposits lining the world's sea beds, astronomers have high confidence supernovae exploded near Earth during the transition from the Pliocene Epoch to the Ice Age.

Iron-60 is extremely rare on this planet with no known natural means to produce it, which leaves arrival from space as the logical origin.

The team calculated the ionisation of the atmosphere from cosmic rays which would come 'from a supernova about as far away as the iron-60 deposits indicate,' Professor Melott said.

Ionisation is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons.

'Usually, you don't get lower-atmosphere ionisation because cosmic rays don't penetrate that far, but the more energetic ones from supernovae come right down to the surface - so there would be a lot of electrons being knocked out of the atmosphere,' he added.

As far back as eight million years ago, prehistoric humans, or proto humans, lived their lives on all fours before shifting to two. Exactly why and when our distant ancestors stood upright and started moving around on two feet is still widely debated. Here, artist's impression

Ionisation in the lower atmosphere meant an abundance of electrons would form more pathways for lightning strikes, according to Professor Melott.

'When high-energy cosmic rays hit atoms and molecules in the atmosphere, they knock electrons out of them - so these electrons are running around loose instead of bound to atoms,' he added.

Lightning occurs when there's a buildup of voltage between clouds or the clouds and the ground.

The current can't flow because not enough electrons are around to carry it so it has to build up high voltage before electrons start moving.

These knock more electrons out of more atoms and it builds to a lightning bolt.

But with ionisation that process can get started a lot more easily, resulting in far more lightning bolts.

WHAT IS A SUPERNOVA AND HOW DOES IT FORM?

A supernova occurs when a star explodes, shooting debris and particles into space.

A supernova burns for only a short period of time, but it can tell scientists a lot about how the universe began.

One kind of supernova has shown scientists that we live in an expanding universe, one that is growing at an ever increasing rate.

Scientists have also determined that supernovas play a key role in distributing elements throughout the universe.

In 1987, astronomers spotted a ‘titanic supernova’ in a nearby galaxy blazing with the power of over 100 million suns (pictured)

There are two known types of supernova.

The first type occurs in binary star systems when one of the two stars, a carbon-oxygen white dwarf, steals matter from its companion star.

Eventually, the white dwarf accumulates too much matter, causing the star to explode, resulting in a supernova.

The second type of supernova occurs at the end of a single star's lifetime.

As the star runs out of nuclear fuel, some of its mass flows into its core.

Eventually, the core is so heavy it can't stand its own gravitational force and the core collapses, resulting in another giant explosion.

Many elements found on Earth are made in the core of stars and these elements travel on to form new stars, planets and everything else in the universe.

The probability of a lightning spike kicking off an upsurge in wildfires is supported by the discovery of carbon deposits found in soils.

Researchers found that these soils corresponded with the timing of the cosmic-ray bombardment, lending more credence to their theory.

The observation is that there's a lot more charcoal and soot in the world starting a few million years ago,' Professor Melott said.

'It's all over the place, and nobody has any explanation for why it would have happened all over the world in different climate zones.

No such event is likely to occur again anytime soon.

The nearest star capable of exploding into a supernova in the next million years is Betelgeuse, some 652 light years from Earth.

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2019-05-28 13:01:07Z
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SpaceX wants to offer Starlink internet to consumers after just six launches - Teslarati

By Eric Ralph

Posted on May 28, 2019

SpaceX has created a brand new website dedicated to its Starlink satellite constellation, a prelude to offering Internet service to consumers after as few as six launches.

Additionally, Starlink.com reiterated CEO Elon Musk’s estimate that SpaceX will conduct 2-6 dedicated Starlink launches – carrying at least 60 satellites each – in 2019 alone. In other words, a best-case satellite deployment scenario could mean that SpaceX will be able to start offering Starlink service to consumers “in the Northern U.S. and Canadian latitudes” as early as this year, while commercial offerings would thus be all but guaranteed in 2020. A step further, SpaceX believes it will be able to offer coverage of the entirety of the populated world after as few as 24 launches (~1500 Starlink satellites).

“Starlink is targeted to offer service in the Northern U.S. and Canadian latitudes after six launches, rapidly expanding to global coverage of the populated world after an expected 24 launches. SpaceX is targeting two to six Starlink launches by the end of this year.” — SpaceX, Starlink.com

This quiet announcement of SpaceX’s expected initial operational capability (IOC) confirms that the company’s plans to offer communications services to consumers are just as ambitious as its 60-satellite, 18.5 ton (~40,000 lb) Starlink launch debut. Assuming an average of 60 Starlink satellites per launch, SpaceX wants to begin serving customers in the US and Canada as soon as ~360 spacecraft are in orbit, a milestone that could occur as early as late 2019. Sometime in the first half of 2020 is arguably far more likely, but the fact alone that service could be offered in 2019 illustrates just how far SpaceX is ahead of its competitors, of which only OneWeb seems to pose an actual threat.

On February 27th, OneWeb launched its first six satellites – down from a planned ten, already ~20 satellites short of a ‘full’ launch – as a mix between its first orbital test and the first launch of operational spacecraft. OneWeb’s initial constellation will feature 648 satellites, potentially rising to 900 and eventually ~2000 in the years to come, pending commercial success and investor interest. The company currently has plans to begin a monthly launch campaign of ~20 Soyuz rockets no earlier than than August or September 2019, likely completing the first phase of its constellation sometime in 2021.

“OneWeb and its satellite manufacturing partner Airbus Defence and Space have crammed 10 gigabits per second of capacity into spacecraft the size of dishwashers. Tom Enders, Airbus Group’s outgoing CEO, said Feb. 14 that OneWeb satellites cost $1 million each to produce, and that the companies will be able to complete 350 to 400 satellites annually from their joint venture OneWeb Satellite’s $85 million Florida factory opening in April. The first batches of Florida-built satellites should be delivered to OneWeb toward the end of the third quarter, Airbus spokesman Guilhem Boltz said.”

SpaceNews, March 2019

Assuming SpaceX aims to launch one dedicated 60-satellite Starlink mission every 6-8 weeks, the company could easily have a constellation of more than 600 satellites in orbit by the end of 2020. Compared to OneWeb, each Starlink satellite weighs about 40% more (~150 kg vs. ~230 kg) but also offers almost double the usable throughput (~17-20 Gbps vs. OneWeb’s ~10 Gbps). In short, SpaceX should be able to offer the same capacity of coverage and service as soon – if not far sooner – than OneWeb, while constellation hopefuls like Telesat, LeoSat, and Amazon’s Project Kuiper are likely 2-5 years away from launching their first satellites, let alone offering service.

Starlink satellites deploy their solar arrays in this official visualization. (SpaceX)

SpaceX’s foray into satellite design

Aside from revealing SpaceX’s tentative schedule for its Starlink service offerings, Starlink.com included excellent, surprisingly detailed renders of satellite hardware, ranging from Dragon-heritage star trackers to the world’s first flightworthy ion thrusters powered by krypton. These renders simply confirm what was already clear: SpaceX has gone against the grain of traditional satellite design at almost every turn, producing a bus (the general structure and form factor) that is unlike almost anything that came before it.

A general overview of Starlink’s bus, launch stacking, and solar array. (SpaceX)

Starlink’s star trackers (left; used for precise pointing and positioning) and what are likely four gyros, also used for pointing and orientation. (SpaceX)

One of Starlink’s krypton ion thrusters is tested at SpaceX’s satellite production facilities. (SpaceX)

As a complete layperson to spacecraft design, it’s hard to describe SpaceX’s first internally designed satellite bus as anything less than elegant. Thanks to their uniquely flat form factor, the satellites can be packed into a Falcon 9 fairing with extreme efficiency, making SpaceX’s first dedicated Starlink launch the company’s heaviest payload ever at more than 18.5 tons (~40,000 lb). For comparison, OneWeb plans to launch approximately 30×150 kg satellites per Soyuz 2.1 launch with a traditional cylindrical adapter, itself weighing ~1000 kg.

For Starlink, the method the 60 satellites use to securely attach to each other remains a minor mystery, only hinted at by photos and renders that show three metal rings/connectors per satellite. However it works, it appears that SpaceX has found a way to launch and deploy dozens of fairly large spacecraft while wasting little to no mass on a dedicated dispenser. Altogether, it appears that SpaceX has already begun to surpass the technological capabilities of its competitors, while also taking large risks with highly innovative, largely unprecedented design choices. All of those characteristics will help as SpaceX pushes to deploy Starlink and begin serving customers as quickly as possible.

Check out Teslarati’s newsletters for prompt updates, on-the-ground perspectives, and unique glimpses of SpaceX’s rocket launch and recovery processes

SpaceX wants to offer Starlink internet to consumers after just six launches

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2019-05-28 11:46:22Z
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Frances Arnold Turns Microbes Into Living Factories - The New York Times

PASADENA, Calif. — The engineer’s mantra, said Frances Arnold, a professor of chemical engineering at the California Institute of Technology, is: “Keep it simple, stupid.” But Dr. Arnold, who last year became just the fifth woman in history to win the Nobel Prize in Chemistry, is the opposite of stupid, and her stories sometimes turn rococo.

Take the happy images on her office Wall of Triumph. Here’s a picture of a beaming President Obama, congratulating Dr. Arnold in 2013 for winning the National Medal of Technology and Innovation.

That must have been a fun event! Sure, Dr. Arnold said. Except for the part where the minibus that delivered the medal recipients to the event caught fire as it pulled up to the White House door. The cabin filled with smoke, passengers were gasping and crying and staggering toward the exit, the younger ones carrying the older ones — and all were greeted by a phalanx of Secret Service agents, guns aimed at the medalists’ heads.

“They must have thought we were terrorists,” Dr. Arnold said. “We were convinced they were going to shoot us.”

Okay. How about this charming picture of Dr. Arnold with the Queen of England in 2015?

Another fun story! When Dr. Arnold and her 16-year-old son, Joe Lange, landed in London after a 12-hour flight from California, the border agent asked what brought them to the United Kingdom. Dr. Arnold, who was “feeling very hot-stuff,” announced she was going to a reception that evening to meet the Queen.

Is that so? the agent said skeptically, eyeing her slightly disheveled appearance. And you are?

A chemical engineer.

And what, pray tell, is next on your agenda?

Next I’m off to an awards ceremony at the president’s palace in Italy, Dr. Arnold replied.

Madam, the agent said, if you are going to Buckingham Palace, you must have an invitation. May I see it, please?

Oh, I don’t have it on me, Dr. Arnold said. It’s packed away in my suitcase.

That’s it, the agent said, shutting his ledger book and grabbing her and Joe’s passports. Come with me, please.

Mother and son spent the next two and a half hours in detention while their story was verified and barely made it to the reception on time.

“They thought I was a kook,” Dr. Arnold said. “Apparently a lot of 60-year-old women say they’re going to meet the Queen.”

Both stories encapsulate another of Dr. Arnold’s maxims: “Give up the thought that you have control. You don’t. The best you can do is adapt, anticipate, be flexible, sense the environment and respond.”

Or maybe not respond. “Joe said to me afterward, ‘Mom, next time why don’t you keep your mouth shut.’”

An engineer’s dream

Dr. Arnold receiving the Nobel Prize from King Carl XVI Gustaf of Sweden in December 2018 in Stockholm.CreditHenrik Montgomery/Agence France-Presse — Getty Images

As it happens, Dr. Arnold, 62, has built a spectacularly successful career on her willingness to cede control in the laboratory to a force much greater than any armed guard or head of state: evolution.

Dr. Arnold won fame and the Nobel Prize for developing a technique called directed evolution, a way of generating a host of novel enzymes and other biomolecules that can be put to any number of uses — detoxifying a chemical spill, or example, or disrupting the mating dance of an agricultural pest. Or removing laundry stains in eco-friendly cold water, or making drugs without relying on eco-hostile metal catalysts.

Rather than seeking to design new proteins rationally, piece by carefully calculated piece — as many protein chemists have tried and mostly failed to do — the Arnold approach lets basic evolutionary algorithms do the work of protein composition and protein upgrades.

The recipe is indeed an engineer’s dream: simple.

You start with a protein that already has some features you’re interested in, such as stability in high heat or a knack for clipping apart fats. Using a standard lab trick such as polymerase chain reaction, you randomly mutate the gene that encodes the protein.

Then you look for slight improvements in the resulting protein — a quickened pace of activity, say, or a vague inclination to carry out a task it wasn’t performing before, or a willingness to operate under conditions it deplored in the past.

You mutate the improved version again and screen the output for even better performance. Repeat as needed. You do your experiments with the help of a bacterial workhorse such as E. coli, or with an exotic microbe isolated from hot springs in Iceland where temperatures can exceed 175 degrees F.

You consciously treat proteins and their carrier microbes exactly as people unconsciously treat disease microbes when blasting them willy-nilly with antibiotics: You encourage the microbes to rise to the challenge, adapt, survive.

Through directed evolution, Dr. Arnold’s lab has generated microbes that do what organisms in nature have never been known to do. Some of them, for instance, stitch together carbon, the element that defines life, and silicon, the stuff of sand, glass and computer chips but heretofore not of life (unless you are a Horta, the rock-shaped beings who famously mind-melded with Mr. Spock on “Star Trek”).

All it took were a few mutational tweaks to a bacterial protein called cytochrome c.

“We showed for the first time that living organisms can use their own machinery to bring carbon and silicon together to form a bond,” said Jennifer Kan, a postdoctoral scholar in Dr. Arnold’s lab who performed the experiments. “We didn’t even have to nag the protein too hard to get it to do it.”

Or how about a mind-meld between carbon and boron, or super-bent carbon rings packed with energy like coiled springs — chemical bonds that had never, or rarely, been seen in living organisms until directed evolution showed them the way?

“In the lab, we’re discovering that nature can do chemistry we never dreamed was possible,” Dr. Arnold said. “We’re adding whole swathes of the periodic table to the chemistry of the biological world.”

Diana Kormos-Buchwald, who directs the Einstein Papers Project at Caltech and is a close friend of Dr. Arnold, said, “Frances essentially invented the field of evolutionary chemistry. Instead of analyzing materials and trying to produce them through standard chemical synthesis, she found a way to use nature itself to populate the landscape of all possible variants of biologically or chemically important molecules.”

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Dr. Arnold has another favorite mantra: “Nature doesn’t care about your calculations.” Analyzing the evolved mutations that proved most effective at tweaking a protein’s performance, the Arnold team found the changes in all sorts of unpredictable places.

“It was far from the active site of the protein, or it was on the surface,” she said. “It was where everybody said it wouldn’t matter but it did matter. I gleefully took the results to the biochemists and said, ‘Nyeh nyeh nyeh, you can’t predict that but I found it, and I’ll do it over and over again.’ That really pissed them off.”

In exploring the outer realms of biochemical bondage, Dr. Arnold is driven by more than intellectual curiosity. (Really, why didn’t nature take advantage of our planet’s abundance of silicon to gin up an earthly version of the Horta?)

As a “card-carrying engineer” with an undergraduate degree in mechanical and aerospace engineering from Princeton, and a doctorate in chemical engineering from the University of California, Berkeley, Dr. Arnold also is motivated by a desire to make useful things.

And because she is an ardent environmentalist, useful means good for the planet.

Directed evolution methods can yield specialized enzymes that will carry out desired reactions far more cleanly and efficiently compared to standard chemical processes, with their reliance on solvents, plastics and precious metals.

“All my projects are about sustainability, bioremediation, making things in a cleaner fashion,” Dr. Arnold said. “I get these students who come in and say, I want to help people. I say, people get plenty of help. Why don’t you help the planet?”

She has started a number of companies, including a business heartily endorsed by Jane Goodall called Provivi, which is devising techniques for synthesizing insect mating pheromones cleanly, cheaply and on an industrial scale, with the goal of fending off agricultural pests through confusion rather than extermination.

In April, Dr. Arnold and three of her former postdocs filed the papers for a start-up called Aralez Bio, which will apply the principles of directed evolution to produce customized amino acids for drug companies.

As currently configured, the pharmaceutical industry is astonishingly “not green,” said Christina Boville, the chief scientific officer of the new venture.

“They produce 100 times more waste than product,” she said. “We think we can do much better, and our technology actually works.”

The young entrepreneurs have reason for optimism: The failure rate for start-ups is something like 90 percent, but the three companies that Dr. Arnold has founded since 2005 are all still in business.

‘Why would I give up?’

Image

Dr. Arnold with her sons Joseph Lange, left, and James Bailey at Caltech last fall. Another son, William Lange, died in an accident in 2016. CreditDamian Dovarganes/Associated Press

Dr. Arnold is sui generis. She projects a charismatic self-confidence rare in anybody, especially a woman — the legacy, perhaps, of growing up as the only daughter among five children.

“I was more of a boy than the boys,” she said.

And smart, to the point of taking high school courses while she was still in grade school. But Dr. Arnold somehow manages to stay on the right side of swaggering.

“She is a unique combination of warm and caring, while also rigorous and no b.s.,” said Mikhail Shapiro, a Caltech professor of chemical engineering who has known Dr. Arnold since 2005, when he sought her help as a first-year graduate student. “I consider her a role model.”

She has notes of both the military and the counterculture. Her grandfather was a three-star general, and her father was a nuclear physicist and in the reserves. But she rebelled against her parents so ferociously that she moved out on her own in Pittsburgh when she was 14, supporting herself by working as a waitress, a taxi driver, in jazz clubs and in pizza parlors.

“You name it, I’ve done it,” she said. Her parents were thrilled when she told them she wanted to go to Princeton, and they happily paid the bills. For all their political and philosophical arguments, Dr. Arnold and her father remained close until his death in 2015.

“We fought all the time,” she said. “But he understood me.”

She has traveled and lived around the world, crisscrossed South America and Indonesia on her own, motorcycled through Europe and Turkey. She speaks five languages and plays guitar, piano and pipe organ.

Dr. Arnold is fast becoming a celebrity. In November she’ll join boldfaced types such as Lin-Manuel Miranda and Jeff Bezos for a Portraits of America ceremony at the Smithsonian’s National Portrait Gallery.

In her office, she has crates overflowing with awards and “literally a thousand invitations” to give talks around the world.

Caltech, where Dr. Arnold has worked for nearly her entire career, has 38 Nobel laureates to its credit, but she is the first woman among them.

“I don’t mind being a celebrity,” she said, because “I photograph better than I look in reality,” which is a lie.

Her friends say she is an outstanding cook. In the acre of garden surrounding her elegantly comfortable 1948 California ranch house near Pasadena, she grows enough food not only for herself but for the local food banks, too: tangerines, oranges, blueberries, lemons, kumquats, artichokes, kale, cucumbers, tomatoes, herbs and spices.

Yes, a charmed life, except — terrible things have happened to her.

Her first marriage, to biochemical engineer Jay Bailey, fell apart in the early 1990s, and he died of colon cancer in 2001. In 2004, Dr. Arnold was diagnosed with breast cancer that had spread to her lymph nodes, and she underwent 18 months of grueling surgery, radiation and chemotherapy, all while raising three young boys and working 60-hour weeks.

“I used to have a photographic memory,” she said. “Chemo knocked that out.”

In 2010, Dr. Arnold’s common-law husband, the cosmologist Andrew Lange, committed suicide, leaving behind a crater of emotional devastation so deep that Dr. Arnold still struggles to forgive him.

Worse by far was the accidental death in 2016 of her middle son, William Lange, at the age of 20, an event that Dr. Arnold says she is not yet ready to talk about.

“Frances did not have an easy life,” said Viviana Gradinaru, a Caltech neuroscientist and close friend of Dr. Arnold. “But despite everything, she got the Nobel Prize.”

Dr. Arnold grows impatient when people express awe at the strength of her spine.

“Nobody is guaranteed an easy life,” she said. “Look at the people in Syria. I have friends who are Holocaust survivors. What was I supposed to do — give up, say I can’t go on? No. I had other children. I had a group of young people in the lab. Why would I give up?”

First, you learn that you have no control. And then you straighten up, fetch your invitation, and go to meet the Queen.

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https://www.nytimes.com/2019/05/28/science/frances-arnold-caltech-evolution.html

2019-05-28 06:33:13Z
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