LightSail Launch Event

LightSail Launch Event

Richard ChuteMay 21, 2019

Planetary Society

LightSail 2’s launch window opens on June 22, and we are finalizing plans for our launch viewing celebrations. Once we have finished coordinating the details with the Air Force’s STP-2 mission team and the Kennedy Space Center, we will share them with all of our members and backers so that you can join us in person or remotely via the internet.

In the meantime, we want to share with you an outline of what we hope to offer. Below, you’ll find our plans to view the launch from the Kennedy Space Center Visitor Center and also information on how to view the launch at home.


Rocket launches are difficult to predict. Equipment issues, payload issues, weather, and other factors all play into the day and timing of the launch and, as a result, launch dates commonly change. Rocket launches are announced as being “no earlier than” (NET) a particular date, and often occur later. Our launch is set for NET June 22. It is possible that it may actually launch that day. It is also quite possible that it won’t. For that reason, anyone planning to join us should have flexible travel. For instance, airfares should include options to change days of travel, and you’ll have to closely manage hotel reservations to be sure that you can cancel or update dates. Expert tip: book accommodations as early as possible since this launch is going to be a very popular one, and hotel rooms are likely to be in short supply.

There is also a risk that we will miss the launch altogether. If the launch is scrubbed late for significant issues and delayed by a number of days, we may travel to Florida only to leave without having seen the launch and without the ability in our schedules (or pocketbooks!) to return for the actual launch days or weeks later. For that reason, it’s important to view the launch celebrations as an opportunity to gather with many other space enthusiasts, to learn more about the mission directly from those running it, to visit Kennedy Space Center, and to celebrate together. The launch is the icing on the cake. Even if we leave without seeing the launch, our later remote viewing experience will be enhanced by our time together.


Rocket launches are remarkably exciting events! If you decide to join us in Florida, you will witness the launch of what is currently the world’s most powerful rocket—the SpaceX Falcon Heavy. And, as it soars aloft, you’ll have a direct connection with this mission since it will be carrying LightSail 2. As a member or backer, you’ll have a real stake in the success of the launch on subsequent flight operations.

Keeping in mind that our plans may change as we obtain new information, we are happy to share our preliminary event plans:

1 day before launch

  • Mission briefing for Planetary Society members and backers from Program Manager and Chief Scientist Bruce Betts; CEO Bill Nye; and members of the engineering team responsible for LightSail 2. The panel will provide a briefing on the LightSail 2 mission and solar sailing. This will be in the late afternoon and will run for about 60 to 90 minutes.
  • At the mission briefing, we will also have a pop-up store with Planetary Society swag (t-shirts, mission patches and stickers, and much more) provided by our retail partners, Yugen Tribe and Chop Shop.
  • A gala reception and dinner. We will host a fundraising reception and dinner under the Shuttle Atlantis. Funds raised will help support launch and operations costs and will be several hundred dollars per ticket. If you are a Kickstarter backer and backed us at the “Party at the Launch” level, then this is already included. Note: sponsorships are available for the gala dinner; contact me for more information at
  • Member and backer meet-up dinners. For those who prefer not to attend the gala dinner, we will organize meet-up style opportunities for members and backers to gather at restaurants in the area with Planetary Society staff on hand to share more about the Society and the LightSail mission.
  • Although details are scarce at this point, Kickstarter is also looking at sponsoring something like a stargazing party either the evening before or after the launch.

    Day of launch

    • Members and backers will attend the launch at Kennedy Space Center Visitor Center (KSC VC). There will be different ticket packages offered by KSC VC at various price levels. You will select a ticket level and purchase it from either us (for the best viewing location at the Saturn V Center) or from KSC VC for other ticket packages.
      • The best tickets for the Saturn V Center are expected to sell out in less than 24 hours. For that reason, we will manage our own Planetary Society ticket block for the Saturn V Center. We will have several hundred tickets available just for Society members and backers.
      • If you were a “Party at the Launch” backer, then the highest-level ticket is already included.
      • If you prefer not to spend on tickets at KSC VC, it will also be possible to see the launch from free, public locations such as parks in the area.
    • After the launch, members and backers with tickets to KSC VC will be able to enjoy the Visitor Center and its exhibits for the rest of the day. During this time, we will also keep participants informed (likely via email) about the successful deployment of our spacecraft from the Falcon Heavy some hours after launch.
    • That evening, we will share information for informal member and backer meet-up launch after-parties so that people can gather to celebrate in restaurants in the area. These will be our last planned group activities.

      If it doesn’t launch on the first day

      • If the launch is canceled on the first day of the launch window, then KSC VC honors the tickets for one additional day. If this happens, we will all head back to the Visitor Center and do it over again!
      • If the launch gets scrubbed a second time, then KSC VC’s tickets expire and we would either leave without getting to see the launch in person, or have to spend additional funds on another ticket, or simply stay in the area and watch from a free, public location.

      If you can’t make it to Florida

      If you can’t see the launch in person, we encourage you to make plans to view the launch at home or with friends or other Planetary Society members at your own launch parties. To support this, we will publish some tips and additional information that you can use to create your own event, and we will live stream our mission briefing so that you can participate remotely. We will also carry a live stream of the launch itself on Whether you are in Florida or Oklahoma or Belgium or Japan, you have a special connection with this launch and can celebrate it with us across multiple regions and time zones.

      After the launch

      After the launch, the real work begins. Several hours after launch, our next mission milestone will be the deployment of Prox-1 with LightSail 2 inside it. One week after Prox-1’s deployment, Prox-1 will deploy LightSail 2. The mission team will then run LightSail 2 through a series of tests. As soon as a few days later LightSail will deploy its solar sail and begin flight operations. We will mark these milestones by reporting on them to you via email, social media, and special blogs and Kickstarter Updates. Each of these moments may offer further opportunities for celebration.

      Final thoughts

      Along with our CEO, Bill Nye, I had the privilege of attending the first test flight of the Falcon Heavy rocket just over a year ago. It was the third rocket launch I’ve been to and it was by far the best experience I’ve had to date. The rocket is extremely powerful and seeing the twin boosters land was amazing. The timing for the upcoming launch isn’t set yet, but we understand that it may be in the early morning hours, which would be visually spectacular.

      What I’ve shared above is all subject to change once we get more detailed information from the Air Force and NASA. We want everyone to come and join us, but you’ll need to do so with “eyes wide open” about the risks and rewards associated with the schedule. I hope this information sketches out a picture of what to expect.

      Stay tuned!

Genetic Astrology

Seven Big Misconceptions About Heredity

Carl Zimmer

This article, adapted from the book, originally appeared as the cover story in the May/June 2019 issue of Skeptical Inquirer.

If someone says, “I guess it’s in my DNA,” you never hear people say, “DN — what?” We all know what DNA is, or at least think we do.

It’s been seven decades since scientists demonstrated that DNA is the molecule of heredity. Since then, a steady stream of books, news programs, and episodes of CSI have made us comfortable with the notion that each of our cells contains three billion base pairs of DNA, which we inherited from our parents. But we’ve gotten comfortable without actually knowing much at all about our own genomes.

Indeed, if you had asked to look at your own genome twenty years ago, the question would have been absurd. It would have been as ridiculous as asking to go to the moon. When scientists unveiled the first rough draft of the human genome in the early 2000s, the final bill came to an Apollo-scale $2.7 billion.

Since then, advances in DNA sequencing and software for analyzing genetic data have steadily brought down the price tag. By 2006, it cost only $14 million to sequence a single human genome. Even at that drastically reduced price, though, only a few big labs with major financial support would dare take on such an expensive project. But in the years that followed, DNA sequencing continued its exponential cost crash, becoming cheap enough to turn into a consumer product.

If you want to get your entire genome sequenced — all three billion base pairs in your DNA — a company called Dante Labs will do it for $699. You don’t need whole genome sequencing to learn a lot about your genes, however. The 20,000 genes that encode our proteins make up less than 2 percent of the human genome. That fraction of the genome — the “exome” — can be yours for just a few hundred dollars. The cheapest insights come from “genotyping” — in which scientists survey around a million spots in the genome known to vary a lot among people. Genotyping — offered by companies such as 23andMe and Ancestry — is typically available for under a hundred dollars.

Thanks to these falling prices, the number of people who are getting a glimpse at their own genes is skyrocketing. By 2019, over twenty-five million worldwide had gotten genotyped or had their DNA sequenced. At its current pace, the total may reach 100 million by 2020.

Future generations will look back at today as a pivotal moment in DNA’s cultural history. People are no longer thinking of their DNA as a black box but as a database to be mined. They’re learning that they have inherited mutations that raise their risk of certain diseases. They’re getting estimates of their ancestry based on genetic markers that are common in certain parts of the world. They’re merging their genetic information with genealogy to discover distant relatives. Some are also discovering some not-so-distant relatives that until now were family secrets.

There’s a lot we can learn about ourselves in these test results. But there’s also a huge opportunity to draw the wrong lessons.

Many people have misconceptions about heredity — how we are connected to our ancestors and how our inheritance from them shapes us. Rather than dispelling those misconceptions, our growing fascination with our DNA may only intensify them. A number of scientists have warned of a new threat they call “genetic astrology.” It’s vitally important to fight these misconceptions about heredity, just as we must fight misconceptions about other fields of science, such as global warming, vaccines, and evolution. Here are just a few examples.

Misconception #1: Finding a Special Ancestor Makes You Special

There are certain clubs to which ancestry is the key to admission. You can get into the Mayflower Society if you descend from the passengers of that famous ship. You can join the Order of the Crown of Charlemagne if you can prove that the Holy Roman Emperor is your ancestor. It’s a thrill to discover we have a genealogical link to someone famous — perhaps because that link seems to make us special, too.

But that’s an illusion. I could join the Mayflower Society, for example, because I’m descended from a servant aboard the ship named John Howland. Howland’s one claim to fame is that he fell out of the Mayflower. Fortunately for me, he got fished out of the water and reached Massachusetts. But I’m not the only fortunate one; by one estimate, there are two million people who descend from him alone.

Mathematicians have analyzed the structure of family trees, and they’ve found that the further back in time you go, the more descendants people had. (This is only true of people who have any living descendants at all, it should be noted.) This finding has an astonishing implication. Since we know Charlemagne has living descendants (thank you, Order of the Crown!), he is likely the ancestor of every living person of European descent. And if you could get in a time machine and travel back a few thousand years, you could find someone who was a common ancestor of all living people on Earth.

Misconception #2: You Are Connected to All Your Ancestors by DNA

When you look at your family tree, you’re looking at a series of branching lines that link you to your ancestors. What exactly flows down through those lines as they travel through time? A few centuries ago, people might say it was blood. In recent decades, blood has been replaced in our popular imagination with DNA. After all, our genes didn’t come out of nowhere. We inherited them.

But genetics do not equal genealogy. It turns out that practically none of the Europeans who descend from Charlemagne inherited any of his DNA. All humans, in fact, have no genetic link to most of their direct ancestors.

The reason for this disconnect is the way that DNA gets passed down from one generation to the next. Every egg or sperm randomly ends up with one copy of each chromosome, coming either from a person’s mother or father. As a result, we inherit about a quarter of our DNA from each grandparent — but only on average. Any one person may inherit extra DNA from one grandparent and less from another. If you go back to the next generation, you’ll find that each great-grandparent contributed approximately an eighth of your DNA — but, again, that’s only an average. Some of them may have contributed much more, others much less.

If you go back a few generations more, that contribution can drop all the way to zero. Graham Coop, a geneticist at the University of California, Davis, and his colleagues have calculated the odds of sharing no DNA with an ancestor as they moved back through the generations. If you go back ten generations, the odds of having DNA from any given ancestor drop to less than 50 percent. They go down even more as you push back further through your ancestry. While it is true that you inherit your DNA from your ancestors, that DNA is only a tiny sampling of the genes in your family tree.

Even without a genetic link, though, your ancestors remain your ancestors. They did indeed help shape who you are — not by giving you a gene for some particular trait, but by raising their own children, who then raised their own children in turn, passing down a cultural inheritance along with a genetic one.

Misconception #3: Ancestry Tests Are as Reliable as Medical Tests

Millions of people are getting ancestry reports based on their DNA. My own report informs me that I’m 43 percent Ashkenazi Jewish, 25 percent Northwestern European, 23 percent South/Central European, 6 percent Southwestern European, and 2.2 percent North Slavic. Those percentages sound impressive, even definitive. It’s easy to conclude that ancestry reports are as reliable as stepping on a scale at the doctor’s office to get your height and weight measured.

That is a mistake, and one that can cause a lot of heartbreak. To estimate ancestry, researchers compare each customer to a database of thousands of people from around the world. Those “reference populations” are typically selected because they have deep roots where they live. Some researchers select only people whose family has lived in the same place for three generations, for example. In each population, there are some genetic variants that are unusually common and others that are unusually rare. Researchers then look for these variants in a customer’s DNA. They can identify stretches of DNA that are likely to have originated in a particular part of the world. While some matches are clear-cut, others are less so. As a result, ancestry estimates always have margins of error — which often go missing in the reports customers get.

To gain more certainty in their estimates, scientists are building up bigger databases. In 2018, unveiled a new set of estimates for its customers. They got a lot of backlash. People who had initially been thrilled to discover a small portion of their ancestry came from Italy or Cameroon were devastated to now learn that they had no such link at all.

These estimates are going to get better with time, but there’s a fundamental limit to what they can tell us about our ancestry. To say I am 43 percent Ashkenazi doesn’t have the same timeless truth as saying I’m 43 percent carbon. Carbon has been carbon for billions of years. But the Ashkenazi people emerged through history. In the Roman Empire, people of Near East and European ancestries came together and started having children. In the Middle Age, Jews in northern and eastern Europe began to be persecuted and formed increasingly isolated communities. In these small groups, children increasingly inherited the same set of genetic variants. From an estimated population of just 350 ancestors, the Ashkenazi population has now reached ten million. They all share a number of distinctive genetic markers from that period of history. But their history reaches farther back in time, to older peoples.

Researchers are getting glimpses of those older peoples by retrieving DNA from ancient skeletons. And they’re finding that our genetic history is far more tumultuous than previously thought. Time and again, researchers find that the people who have lived in a given place in recent centuries have little genetic connection to the people who lived there thousands of years ago. All over the world, populations have expanded and migrated, coming into contact with other populations. In Europe, for example, new waves of genetically distinct people have arrived from elsewhere every few thousand years, either replacing or interbreeding with the people who lived there before. Today, Europeans are genetically similar to each other, but only because the genes of their disparate ancestors — from places such as Africa, Turkey, and Russia — have been well mixed. If you want to find purity in your ancestry, you’re on a fool’s errand.

Misconception #4: There’s a Gene for Every Trait You Inherit

When we learn about genetics in school, we learn about Gregor Mendel. In the 1850s, Mendel crossed lines of pea plants and discovered that their traits — such as the color of their flowers or the texture of their peas — were carried by invisible hereditary factors. Some factors were dominant, meaning that inheriting just one copy of them determined a trait. Other factors were recessive, meaning that they could shape a pea plant if it inherited two copies.

Mendel is a great place to start learning about heredity but a bad place to stop. There are some traits that are determined by a single gene. Whether Mendel’s peas were smooth or wrinkled was determined by a gene called SBEI. Whether people develop sickle cell anemia or not comes down to a single gene called HBB. But many traits do not follow this so-called Mendelian pattern — even ones that we may have been told in school are Mendelian.

Consider your ear lobes. For decades, teachers taught that they could either hang free or be attached to the side of our heads. The sort of ear lobes you had was a Mendelian trait, determined by a single gene. In fact, our ear lobes typically fall somewhere between the two extremes of strongly attached to fully free. In 2017, a team of researchers compared the ear lobes of over 74,000 people to their DNA. They looked for genetic variants that were common in people at either end of the ear-lobe spectrum. They pinpointed forty-nine genes that appear to play a role in determining how attached they are to our heads. There well may be more waiting to be discovered.

None of those forty-nine genes is a gene “for” ear-lobe attachment. That language just doesn’t make sense for the way most genes work. The genes that the scientists identified become active in many cells in an embryo. Some are active in skin cells across the body. Some are active in hair and sweat glands as well. Some help build the intricate anatomy of the inner ear. The attachment of our ear lobes is the result of a symphony performed by these players.

The genetics of ear lobes is actually very simple compared to other traits. Studying height, for example, scientists have identified thousands of genetic variants that appear to play a role. The same holds true for our risk of developing diabetes, heart disease, and other common disorders. We can’t expect to find a single gene in our DNA tests that determines whether we’ll die of a heart attack. Nor should we expect easy fixes for such complex diseases by repairing single genes.

Misconception #5: The Genes You Inherit Explain Exactly Who You Are

Throughout our lives — through our successes and failures, through our joys and suffering — we often wonder how things turned out the way they did. The more that scientists explore our DNA, the easier it is to shrug and say that it was all programmed in our genes.

Take, for example, a recent study on how long people stay in school. Researchers examined DNA from 1.1 million people and found over 1,200 genetic variants that were unusually common either in people who left school early or in people who went on to college or graduate school. They then used the genetic differences in their subjects to come up with a predictive score, which they then tried out on another group of subjects. They found that in the highest-scoring 20 percent of these subjects, 57 percent finished college. In the lowest-scoring 20 percent, only 12 percent did.

But these results don’t mean that how long you stayed in school was determined before birth by your genes. Getting your children’s DNA tested won’t tell you if you should save up money for college tuition or not. Plenty of people in the educational attainment study who got high genetic scores dropped out of high school. Plenty of people who got low scores went on to get PhDs. And many more got an average amount of education in between those extremes. For any individual, these genetic scores make predictions that are barely better than guessing at random.

This confusing state of affairs is the result of how genes and the environment interact. Scientists call a trait such as how long people stay in school “moderately heritable.” In other words, a modest amount of the variation in education attainment is due to genetic variation. Lots of other factors also matter, too — the neighborhoods where people live, the quality of their schools, the stability of their family life, their income, and so on. What’s more, a gene that may have an influence on how long people stay in school in one environment may have no influence at all in another.

Misconception #6: You Have One Genome

In 2002, a woman named Lydia Fairchild applied for enforcement of child support when she separated from the father of her two children. The state of Washington required genetic testing to confirm his paternity. The tests showed he was indeed the father. But they also showed that Fairchild was not the mother.

State officials threatened to charge Fairchild with fraud, despite her protests that she had given birth to the children and the testimony of her mother, who had seen the birth of her grandchildren. When Fairchild went into a hospital to give birth to another child, a court official came to witness the delivery and watch the nurses draw blood for another DNA test. Once more, the test indicated that Fairchild was not the infant’s mother.

This absurd situation arose because of the common assumption that each of us carries a single genome. According to this assumption, you will find an identical sequence of DNA in any cell you examine. But there are many ways in which we can end up with different genomes within our bodies.

Fairchild is known as a chimera. She developed inside her mother alongside a fraternal twin. That twin embryo died in the womb, but not before exchanging cells with Fairchild. Now her body was made up of two populations of cells, each of which multiplied and developed into different tissues. In Fairchild’s case, her blood arose from one population, while her eggs arose from another.

Women can also become chimeras with their own children. During pregnancy, fetuses can shed cells that then circulate throughout a woman’s body. In some cases they linger on after birth. They can then develop into muscle, breast tissue, and even neurons.

It’s unclear how many people are chimeras. Once they were considered bizarre rarities. Scientists became aware of them only in cases such as Lydia Fairchild’s, when their mixed identity made itself known. In recent years, researchers have been carrying out small-scale surveys that suggest that perhaps a few percent of twins are chimeras, but the true number could be higher. As for chimeric mothers, they may be the rule rather than the exception. In a 2017 study, researchers studied brain tumors taken from women who had sons. Eighty percent of them had Y-chromosome-bearing cells in their tumors.

Chimerism is not the only way we can end up with different genomes. Every time a cell in our body divides, there’s a tiny chance that one of the daughter cells may gain a mutation. At first, these new aberrations — called somatic mutations — seemed important only for cancer. But that view has changed as new genome-sequencing technologies have made it possible for scientists to study somatic mutations in many healthy tissues. It now turns out that every person’s body is a mosaic, made up of populations of cells with many different mutations.

Misconception #7: Genes Don’t Matter Because of Epigenetics

The notion that our genes are our destiny can trigger an equally false backlash: that genes don’t matter at all. And very often, those who push against the importance of genetics invoke a younger, more tantalizing field of research: epigenetics.

Ask five scientists to define epigenetics and you may get five different definitions. But they will all center on the fact that genes, on their own, do nothing. They simply store information that our cells can use as guides for building proteins or RNA molecules. But our cells only use genes in response to certain combinations of signals. It can be disastrous to use genes at the wrong time or in the wrong place. Genes involved in making enamel need to be switched on in developing teeth. But you wouldn’t want your skin cells to make it too, trapping you in an enamel sarcophagus.

Our cells use many layers of control to make proper use of their genes. They can quickly turn some genes on and off in response to quick changes in their environment. But they can also silence genes for life. Women, for example, have two copies of the X chromosome, but in early development, each of their cells produces a swarm of RNA molecules and proteins that clamp down on one copy. The cell then only uses the other X chromosome. And if the cell divides, its daughter cells will silence the same copy again.

One of the most tantalizing possibilities scientists are now exploring is whether certain epigenetic “marks” can be inherited not just by daughter cells but by daughters — and sons. If people experience trauma in their lives and it leaves an epigenetic mark on their genes, for example, can they pass down those marks to future generations?

If you’re a plant, the answer is definitely yes. Plants that endure droughts or attacks by insects can reprogram their seeds, and these epigenetic changes can get carried down several generations. The evidence from animals is, for now, still a mixed bag. In one intriguing experiment, researchers separated male mouse pups from their mothers from time to time, causing them stress. Later, they used sperm from those stressed mice to fertilize eggs, and some of their descendants proved to be unusually sensitive to stress. But skeptics have questioned how epigenetics can transmit these traits through the generations, suggesting that the results are just statistical flukes. That hasn’t stopped a cottage industry of epigenetic self-help from springing up. You can join epigenetic yoga classes to rewrite your epigenetic marks or go to epigenetic psychotherapy sessions to overcome the epigenetic legacy you inherited from your grandparents.

You may feel more limber after your yoga class. And you may feel better after having talked about your anxiety. But your genes will still work much the same as they did before.


Manden bag Shodan

Manden bag fænomenet Shodan: Jeg havde ikke troet, det ville blive så stort

Da John Matherly først viste sin idé frem blev han blandt andre hånet af Microsoft. Nu har hans kontroversielle tjeneste 2,5 millioner brugere, og Matherly fastholder, at Shodans hensigter er gode.

Med Shodan kan man som bruger hurtigt slå op i internettets afkroge og blandt andet finde ud af, hvilke softwareversioner diverse onlinetjeneste kører.

Det kan man bruge til at sikre sig, at ens tjenester kører den seneste version, men eventuelle hackere kan også bruge Shodan til at holde øje med, hvilke tjenester der er opdaterede og dermed sikre.

Og på den måde målrette angreb mod de tjenester, der ikke er beskyttede.

Bag den populære og, ifølge to danske sikkerhedsforskere lidt for effektive, tjeneste er schweizer-amerikaneren John Matherly, der startede det succesfulde projekt op selv.

»Folk har altid spurgt mig, om ikke jeg gik de kriminelles ærinde. Men det har aldrig været mit udgangspunkt,« siger John Matherly til Version2 og fortæller, at Shodan startede med udgangspunkt i Business Intelligence, ikke sikkerhed.

Startede ikke som sikkerhedsværktøj

Idéen om at scanne internettets opkoblede enheder og sider for metadata og indeksere dem er ikke ny. Shodan er ikke alene på markedet, og var heller ikke først.

Men Shodan er størst nu, og sikkerhedsfolk og andre ‘sikkerheds-interesserede’ bruger flittigt sitet, der definerer sig selv som en ‘søgemaskine baseret på datamining’.

Tjenesten skulle hjælpe virksomheder med at finde alle deres opkoblede enheder, skabe et overblik.

»Jeg vidste, at store virksomheder som Microsoft betalte en del for det her på eksisterende tjenester som Netcraft, som dengang kun kiggede på netservere og desuden havde lukkede dataset,« siger John Matherly.

Hånet af Microsoft

Derfor besluttede han sig for at brede søgningen ud. Jo flere IP’er jo bedre. Shodan skulle ikke kun holde sig til www, men sweepe hele internettet.

Og så ville John Matherly åbne delvist op for de enorme dataset, en sådan scanning afføder. Kvit og frit.

»Men jeg er ikke en særligt god sælger. Så da jeg første gang pitchede mit koncept på en Black Hat-konference, blev jeg til grin. Microsoft grinede af mig, og troede ikke, det var muligt at samle alle de her metadata på en meningsfuld måde« siger John Matherly med en vis bitterhed i stemmen.

»Nu er de mine kunder.«

Et tweet ændrede alt

Det var især ét tweet, der gjorde forskellen for John Matherly, der dengang havde sølle 30 følgere på Twitter. Han skriver til sin lille skare af følgere, at en prototype på Shodan er klar til brug.
Og så går det ellers stærkt.

»Flere prominente sikkerhedsforskere bruger Shodan til at finde bunkevis af sårbarheder,« siger John Matherly og beskriver, hvordan interessen for hans projekt eksploderede indtil det nåede det niveau, det har i dag.

De 30 følgere er blevet til mere end 20.000 og ifølge Shodans egne tal abonnerer 56% af de såkaldte Fortune 100-virksomheder på selskabets tjenester for at holde styr på deres sikkerhed. Shodan har mere end 2,5 millioner unikke brugere.

»Det viser bare at jeg havde ret, da jeg i lang tid uden interesse for Shodan gjorde det rigtige ved at holde fast i in idé og tro på den.

Et tveægget sværd

Shodan er ikke alene på markedet.

Blandt Shodans konkurrenter er blandt andre, der ifølge it-sikekrhedskonsulenten Keld Norman fra Dubex er en smule mere analytisk.

Derfor er Shodan heller ikke alene om at arbejde i det etiske grænseland der opstår, når man scanner internettet og publicerer informationer, der på mange måder er definerende for sikkerheden på sites og devices verden over.

»Folk render rundt og laver ulykker med Shodan. Overalt. Det er det perfekte sted at starte som hacker, indtil man selv har inficerede maskiner nok til at scanne internettet,« siger Keld Norman, der kritiserer sitet for at tydeliggøre it-usikkerheder verden over.

Sammen med sikkerhedskonsulenten Claus Vesthammer fra Improsec kritiserer han Shodan for at gøre det legende let for hackere at spotte sårbarheder i systemer.

Fastholder uskyld

»Det er noget pjat, at Shodan skulle hjælpe kriminelle. Det vi gør er at vi hjælper virksomheder med at forstå, hvad der er forbundet til internettet hos dem,« siger John Matherly og giver et eksempel.

»Hvordan skulle en stor virksomhed finde ud af, om en medarbejder har sat en åben server op ved en fejl? Sådan noget ville Shodan opdage på et splitsekund.«

John Matherly fortæller desuden, at det efter den verdensomspændende sårbarhed Heartbleed var nemt med Shodan at se om ens devices var opdateret og patchet for sårbarheden eller ej.

»Vi kigger aldrig bag folks firewalls, og vi indtaster aldrig så meget som ét kodeord for at se, om folk stadig bruger de kodeord, de fik med da de i sin tid købte produktet,« garanterer John Matherly.


Results from KBO 2014 MU69

Initial results from the New Horizons exploration of 2014 MU69, a small Kuiper Belt object

S.A. Stern et al., Science 17 May 2019

New Horizons flies past MU69

After flying past Pluto in 2015, the New Horizons spacecraft shifted course to encounter (486958) 2014 MU69, a much smaller body about 30 kilometers in diameter. MU69 is part of the Kuiper Belt, a collection of small icy bodies orbiting in the outer Solar System. Stern et al. present the initial results from the New Horizons flyby of MU69 on 1 January 2019. MU69 consists of two lobes that appear to have merged at low speed, producing a contact binary. This type of Kuiper Belt object is mostly undisturbed since the formation of the Solar System and so will preserve clues about that process.

(A) MVIC enhanced color image at a scale of 1.5 km per pixel. (B) CA04 LORRI image at 140 m per pixel. (C) (A) overlaid on (B). (D) MVIC color measurements (colored points) and a LEISA near-IR spectrum of MU69 (black points). Data at wavelengths shorter than 1 μm are from the MVIC visible/near-IR color imager at a phase angle of 11.7°; data at wavelengths longer than 1.2 μm are from the LEISA IR spectrograph at a phase angle of 12.6° and a mean spatial scale of 1.9 km per pixel. The MVIC data are split into multiple terrain units (Ultima and Thule lobes, the bright neck region, and a combination of all other bright spots identified in LORRI data); the LEISA spectrum is a global average. All LEISA data points illustrate an estimated 1σ uncertainty; MVIC data points illustrate an estimated 1σ uncertainty relative to the red channel flux. The data are compared to Hapke model spectra shown as the brown dot-dashed line of 2002 VE95 and the magenta dashed line of 5145 Pholus. Those curves are scaled by 0.45 and 0.84, respectively, to match the average near IR I/F of MU69. The apparent wavelength shifts of some features in the MU69 spectrum relative to the dashed models are likely due to unmodeled temperature, particle size, and temperature effects. Tentative identifications of absorption bands of water and methanol ices are marked, along with an unknown feature at 1.8 μm.

Structured Abstract


The Kuiper Belt is a broad, torus-shaped region in the outer Solar System beyond Neptune’s orbit. It contains primordial planetary building blocks and dwarf planets. NASA’s New Horizons spacecraft conducted a flyby of Pluto and its system of moons on 14 July 2015. New Horizons then continued farther into the Kuiper Belt, adjusting its trajectory to fly close to the small Kuiper Belt object (486958) 2014 MU69 (henceforth MU69; also informally known as Ultima Thule). Stellar occultation observations in 2017 showed that MU69 was ~25 to 35 km in diameter, and therefore smaller than the diameter of Pluto (2375 km) by a factor of ~100 and less massive than Pluto by a factor of ~106. MU69 is located about 1.6 billion kilometers farther from the Sun than Pluto was at the time of the New Horizons flyby. MU69’s orbit indicates that it is a “cold classical” Kuiper Belt object, thought to be the least dynamically evolved population in the Solar System. A major goal of flying past this target is to investigate accretion processes in the outer Solar System and how those processes led to the formation of the planets. Because no small Kuiper Belt object had previously been explored by spacecraft, we also sought to provide a close-up look at such a body’s geology and composition, and to search for satellites, rings, and evidence of present or past atmosphere. We report initial scientific results and interpretations from that flyby.


The New Horizons spacecraft completed its MU69 flyby on 1 January 2019, with a closest approach distance of 3538 km—less than one-third of its closest distance to Pluto. During the high-speed flyby, made at 14.4 km s−1, the spacecraft collected ~50 gigabits of high-resolution imaging, compositional spectroscopy, temperature measurements, and other data on this Kuiper Belt object. We analyzed the initial returned flyby data from the seven scientific instruments carried on the spacecraft: the Ralph multicolor/panchromatic camera and mapping infrared composition spectrometer; the Long Range Reconnaissance Imager (LORRI) long–focal length panchromatic visible imager; the Alice extreme/far ultraviolet mapping spectrograph; the Radio Experiment (REX); the Solar Wind Around Pluto (SWAP) solar wind detector; the Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) high-energy charged particle spectrometer; and the Venetia Burney Student Dust Counter (VBSDC), a dust impact detector.


Imaging of MU69 showed it to be a bilobed, contact binary. MU69’s two lobes appear to have formed close to one another, becoming an orbiting pair that subsequently underwent coupled tidal and orbital evolution to merge into the contact binary we observe today. The object rotates on its axis every 15.92 hours; its rotation pole is inclined approximately 98° to the plane of its heliocentric orbit. Its entire surface has a low visible-wavelength reflectivity (albedo) but displays brighter and darker regions across its surface, ranging from 5 to 12% reflectivity. The brightest observed regions are the “neck” of MU69, where the two lobes are joined, and two discrete bright spots inside the largest crater-like feature on the object’s surface. Although MU69’s albedo varies substantially across its surface, it is uniformly red in color, with only minor observed color variations. This coloration likely represents a refractory residue from ices and organic molecules processed by ultraviolet light and cosmic rays. Spectra of the surface revealed tentative absorption band detections due to water ice and methanol. The geology of MU69 consists of numerous distinct units but shows only a small number of craters, providing evidence that there is a deficit of Kuiper Belt objects smaller than ~1 km in diameter, and that there is a comparatively low collision rate in its Kuiper Belt environment compared to what would be expected in a collisional equilibrium population. A three-dimensional shape model derived from the images shows MU69 is not simply elongated but also flattened. The larger lobe was found to be lenticular, with dimensions of approximately 22 × 20 × 7 km (uncertainty <0.6 × 1 × 2 km), whereas the smaller lobe is less lenticular, with dimensions of approximately 14 × 14 × 10 km (uncertainty <0.4 × 0.7 × 3 km). No evidence of satellites, rings, or an extant atmosphere was found around MU69.


Both MU69’s binarity and unusual shape may be common among similarly sized Kuiper Belt objects. The observation that its two lobes are discrete, have retained their basic shapes, and do not display prominent deformation or other geological features indicative of an energetic or disruptive collision indicates that MU69 is the product of a gentle merger of two independently formed bodies.


The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU69, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU69 is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU69’s origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.


The Kuiper Belt, a torus-shaped ensemble of objects in the outer Solar System beyond the orbit of Neptune, was discovered in 1992. This is the source region for Jupiter-family comets and contains primordial planetesimals and dwarf planets. The 2003 Planetary Decadal Survey ranked exploration of the Kuiper Belt at the top of funding priorities for NASA’s planetary program. The resultant NASA mission, New Horizons, flew through and explored the Pluto dwarf planet system in 2015. The spacecraft has since continued farther to explore Kuiper Belt objects (KBOs) and the Kuiper Belt radiation and dust environment.

The target selected for the subsequent New Horizons KBO flyby was (486958) 2014 MU69 (hereafter MU69, also informally referred to as Ultima Thule). This KBO was discovered in 2014 when the Hubble Space Telescope (HST) was being used to conduct a dedicated search for New Horizons KBO flyby targets. Before the arrival of New Horizons, the only definitive facts regarding MU69 were its orbit, its red color, its size of ~30 km, and its lack of detectable variations in its light curve or large, distant satellites.

MU69’s orbit has a semimajor axis a = 44.6 astronomical units (AU), with eccentricity e = 0.042 and inclination i = 2.45°, making it a member of the cold classical KBO (CCKBO) population (here, cold refers to low dynamical excitation, not surface temperature). CCKBOs are thought to be (i) distant relics formed from the Solar System’s original protoplanetary disk and (ii) more or less dynamically undisturbed bodies that therefore formed in situ ~4.5 billion years ago and have since remained at or close to their current, large heliocentric distances. Relative to other Kuiper Belt populations, CCKBOs have a more uniformly red color distribution, as well as a different size-frequency distribution (i.e., the population of objects as a function of object size) and higher average visible albedos than are typical in the Kuiper Belt. Additionally, many CCKBOs have satellites.

Because CCKBOs are dynamically undisturbed from their formation location, they have never been warmed above the ambient, radiative equilibrium temperatures of 30 to 60 K in the Kuiper Belt. MU69’s small equivalent spherical diameter of ~19 km is insufficient to drive internal evolution long after its formation. Therefore, small CCKBOs like MU69 are expected to be primordial planetesimals, preserving information on the physical, chemical, and accretional conditions in the outer solar nebula and the processes of planetesimal formation.

New Horizons flew closest to MU69 at 05:33:22.4 (±0.2 s, 1σ) universal time (UT) on 1 January 2019. The closest approach distance of 3538.5 ± 0.2 (1σ) km was targeted to the celestial north of MU69’s center; its relative speed past MU69 was 14.43 km s–1. The asymptotic approach direction of the trajectory was approximately in the ecliptic plane at an angle of 11.6° from the direction to the Sun. The flyby’s observation planning details have been summarized elsewhere. This report of initial flyby results is based on the ~10% of all collected flyby data that had been sent to Earth before 1 March 2019; full data transmission is expected to complete in mid-2020.

New Horizons carries a suite of seven scientific instruments; all were used in the flyby of MU69. These instruments are (i) Ralph, which consists of the Multispectral Visible Imaging Camera (MVIC), a multicolor/panchromatic mapper, and the Linear Etalon Imaging Spectral Array (LEISA), an infrared (IR) composition mapping spectrometer; (ii) the Long Range Reconnaissance Imager (LORRI), a long–focal length panchromatic visible camera; (iii) the Alice extreme/far ultraviolet mapping spectrograph; (iv) a Radio Experiment (REX) to measure surface brightness temperatures and X-band radar reflectivity; (v) the Solar Wind Around Pluto (SWAP) charged-particle solar wind spectrometer; (vi) the Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) MeV charged-particle spectrometer; and (vii) the Venetia Burney Student Dust Counter (VBSDC), a dust impact detector.


MDS attacs on Intel CPUs

Attacks on the newly-disclosed “MDS” hardware vulnerabilities in Intel CPUs

The RIDL and Fallout speculative execution attacks allow attackers to leak confidential data across arbitrary security boundaries on a victim system, for instance compromising data held in the cloud or leaking your information to malicious websites. Our attacks leak data by exploiting the newly disclosed Microarchitectural Data Sampling (or MDS) side-channel vulnerabilities in Intel CPUs. Unlike existing attacks, our attacks can leak arbitrary in-flight data from CPU-internal buffers (Line Fill Buffers, Load Ports, Store Buffers), including data never stored in CPU caches. We show that existing defenses against speculative execution attacks are inadequate, and in some cases actually make things worse. Attackers can use our attacks to obtain sensitive data despite mitigations, due to vulnerabilities deep inside Intel CPUs.


RIDL (Rogue In-Flight Data Load) shows attackers can exploit MDS vulnerabilities to mount practical attacks and leak sensitive data in real-world settings. By analyzing the impact on the CPU pipeline, we developed a variety of practical exploits leaking in-flight data from different internal CPU buffers (such as Line-Fill Buffers and Load Ports), used by the CPU while loading or storing data from memory.

We show that attackers who can run unprivileged code on machines with recent Intel CPUs – whether using shared cloud computing resources, or using JavaScript on a malicious website or advertisement – can steal data from other programs running on the same machine, across any security boundary: other applications, the operating system kernel, other VMs (e.g., in the cloud), or even secure (SGX) enclaves.

We will present our paper on these attacks at the 40th IEEE Symposium on Security and Privacy, on May 20th 2019.


Fallout demonstrates that attackers can leak data from Store Buffers, which are used every time a CPU pipeline needs to store any data. Making things worse, an unprivileged attacker can then later pick which data they leak from the CPU’s Store Buffer.

We show that Fallout can be used to break Kernel Address Space Layout Randomization (KASLR), as well as to leak sensitive data written to memory by the operating system kernel.

Ironically, the recent hardware countermeasures introduced by Intel in recent Coffee Lake Refresh i9 CPUs to prevent Meltdown make them more vulnerable to Fallout, compared to older generation hardware.

PS: This server has been updated for The RIDL and Fallout speculative execution attacks.


Inflatable heat shield

NASA, ULA find launch opportunity for inflatable heat shield demonstrator

Artist’s illustration of the the Low Earth Orbit Flight Test of an Inflatable Decelerator, or LOFTID, spacecraft. Credit: NASA

A flight demonstration of an inflatable heat shield that could be used to retrieve reusable engines from United Launch Alliance’s next-generation Vulcan rocket, and for the delivery of heavier cargo to the surface of Mars, is planned for launch in late 2021 or early 2022 as a piggyback payload on an Atlas 5 rocket with a NOAA weather satellite.

The inflatable re-entry decelerator will launch as a joint project between NASA and ULA, which foresee different uses for the technology.

ULA aims to recover engines from the company’s new Vulcan rocket, set to debut in 2021, using an inflatable heat shield and a parafoil. A helicopter equipped with a boom will snag the parafoil in a mid-air recovery, preventing contamination from salt water if the engines splashed down in the ocean.

The inflatable heat shield is much lighter than a rigid heat shield, such as thermal protection systems used on crew capsules, and take up less volume inside a rocket’s payload fairing. The technology will allow future NASA missions to deliver more massive rovers, landers, and eventually human-rated habitats to the Martian surface.

The heaviest spacecraft ever landed on Mars using current technology was the Curiosity rover, which weighed less than a ton at touchdown in 2012.

Inflatable heat shield technology could also protect materials manufactured in space during the return trip to Earth.

“It has the potential for returning substantial mass back to Earth,” said Jim Reuter, associate administrator of NASA’s space technology mission directorate, during an April 30 meeting of the NASA Advisory Council’s technology, innovation and engineering committee.

The Low Earth Orbit Flight Test of an Inflatable Decelerator will test a nearly 20-foot-diameter (6-meter) heat shield, the largest blunt body atmospheric entry vehicle ever flown in space.

NASA and ULA have identified room for the re-entry testbed, known by the acronym LOFTID, as a secondary payload on an Atlas 5 launch in late 2021 or early 2022 from Vandenberg Air Force Base, California, with NOAA’s Joint Polar Satellite System-2, or JPSS 2, weather observatory heading for polar orbit, according to Reuter.

Officials said NOAA recently agreed to launch the LOFTID experiment with the JPSS 2 satellite, after a search for excess capacity on Atlas 5 missions launching from Vandenberg over the next few years.

Therese Griebel, deputy associate administrator for programs in NASA’s technology division, said a recent review with JPSS 2 program managers concluded the addition of the LOFTID experiment on the launch would add no significant risk to the mission.

“It looks like we’ve gotten everybody on-board (with launching LOFTID with JPSS),” Reuter said.

The JPSS 2 satellite has a targeted launch readiness date in the first quarter of fiscal year 2022, or late in the calendar year 2021, according to John Leslie, a NOAA spokesperson.

NASA, which provides launch and spacecraft development support to NOAA’s weather satellites, selected ULA’s Atlas 5 rocket in 2017 to carry the JPSS 2 spacecraft into orbit. The lightest version of the Atlas 5 rocket, a variant known as the Atlas 5-401 without any solid rocket boosters, will launch the JPSS 2 satellite.

But JPSS 2 fills less than half of the Atlas 5-401’s capacity to the weather satellite’s 512-mile-high (824-kilometer) orbit, leaving ample room for secondary payloads.

Last year, NOAA released a request for information soliciting ideas for small commercial Earth observation satellites that could ride piggyback on the JPSS 2 launch. With agreement from NASA, NOAA and ULA, part of the excess capacity on the Atlas 5 rocket will be filled with the LOFTID experiment.

The LOFTID re-entry vehicle will weigh around 2,700 pounds (1,224 kilograms).

Under the terms of a no-funds-exchanged Space Act Agreement, NASA will provide the re-entry vehicle and its inflatable aeroshell. ULA will supply the high-pressure tanks to inflate the heat shield in space and the Atlas 5 launch services at no cost to NASA.

NASA’s Langley Research Center in Virginia heads the agency’s work on the LOFTID experiment.

NASA awarded ULA a separate $1.9 million contract last year to demonstrate mid-air retrieval of the LOFTID entry vehicle, using an ocean-going ship capable of transporting a helicopter to the recovery zone.

The LOFTID experiment will test a flexible thermal protection system using braided synthetic fibers that are 15 times stronger than steel, according to a NASA fact sheet. Unlike rigid heat shields, the material allows the structure to be folded and packed in a tighter volume that can fit inside the payload envelope of existing rockets.

During the LOFTID demonstration, the heat shield will inflate after the Atlas 5 rocket releases the JPSS 2 spacecraft in orbit. After inflation, the Atlas 5’s Centaur upper stage will execute a deorbit burn on a trajectory heading back into the atmosphere, then deploy the LOFTID vehicle for re-entry.

ULA’s interest in inflatable heat shield technology stems from the company’s plan to recover first stage engines from the next-generation Vulcan rocket for refurbishment and reuse.

The Vulcan rocket is scheduled for its inaugural launch from Cape Canaveral in 2021. Two BE-4 main engines, built by Blue Origin, will power the Vulcan’s first stage.

Unlike SpaceX, which lands entire Falcon 9 first stage boosters to be reused, ULA plans to jettison the BE-4 engine pod from the base of the Vulcan first stage. The engines will be shielded by an inflatable decelerator, similar to the system to be demonstrated by the LOFTID experiment, then unfurl a steerable parafoil for a helicopter to capture in mid-air.

The BE-4 engines, which burn methane and liquid oxygen, are designed to be reusable. Blue Origin’s own New Glenn rocket, also set for a debut in 2021, will also use BE-4 engines on its first stage. Like SpaceX, Blue Origin intends to land the New Glenn’s first stage intact for refurbishment and reuse.

ULA will discard the BE-4 engines on the initial flights of the Vulcan rocket. The company plans to begin retrieving the engines around 2024.


The HAYABUSA2 Project

The Crater Search Operation (Post-SCI): (CRA2)

The Small Carry-on Impactor (SCI) operation successfully took place on April 5. A 2kg copper mass was fired using the collision apparatus to collide with Ryugu. The gravel released from the surface of Ryugu was photographed by the deployable camera, DCAM3. However, the images from DCAM3 do not show how Ryugu’s surface has been altered by the impact. Hayabusa2 will therefore descend and make observations in the vicinity of the SCI collision area.

The CRA2 operation will take place from April 23 – 25, 2019, with preparation for the descent beginning on April 23, the descent itself starting on April 24 and the observations at the lowest altitude (about 1.7km) on April 25. The spacecraft will then rise on April 25. Figure 1 shows the location of the observations. The area to be observed is the same as that observed on March 22 in the Crater Search Operation (Pre-SCI) (CRA1).

The schedule for the CRA2 operation is shown in Figure 2. The spacecraft begins its descent at a speed of 0.4 m/s on April 24 at 16:42 JST (all times are onboard times). The speed is reduced to 0.1 m/s on April 25 at around 03:02. The descent will then continue and reach the lowest altitude (at about 1.7 km) at round 11:16 and continue to observe at this altitude for a while. The spacecraft will begin to rise at 12:53 and return to the home position. Please note that these are the planned times and the actual operation time may vary.

Figure 2: Schematic diagram of the CRA 2 operation. (Image credit: JAXA).
Note that the times listed here may differ during the actual operation.


Gravity waves in blue subergiants

Low-frequency gravity waves in blue supergiants revealed by high-precision space photometry

Dominic M. Bowman et al.

Nature Astronomy (2019)

Almost all massive stars explode as supernovae and form a black hole or neutron star. The remnant mass and the impact of the chemical yield on subsequent star formation and galactic evolution strongly depend on the internal physics of the progenitor star, which is currently not well understood. The theoretical uncertainties of stellar interiors accumulate with stellar age, which is particularly pertinent for the blue supergiant phase. Stellar oscillations represent a unique method of probing stellar interiors, yet inference for blue supergiants is hampered by a dearth of observed pulsation modes. Here we report the detection of diverse variability in blue supergiants using the K2 and TESS space missions. The discovery of pulsation modes or an entire spectrum of low-frequency gravity waves in these stars allow us to map the evolution of hot massive stars towards the ends of their lives. Future asteroseismic modelling will provide constraints on ages, core masses, interior mixing, rotation and angular momentum transport. The discovery of variability in blue supergiants is a step towards a data-driven empirical calibration of theoretical evolution models for the most massive stars in the Universe.


Blue Moon lunar lander

Blue Moon lunar lander

Blue Moon lunar landerBlue Origin announced Blue Moon, its large lunar lander capable of delivering multiple metric tons of payload to the lunar surface based on configuration and mission. The cargo variant revealed today can carry 3.6 metric tons to the surface. We have also designed a variant of the lander that can stretch to be capable of carrying a 6.5-metric-ton, human-rated ascent stage. Blue also announced it can meet the current Administration’s goal of putting Americans on the Moon by 2024 with the Blue Moon lunar lander.

BE-7 engineThe Blue Moon lunar lander will be powered by the BE-7 engine, a new addition to Blue Origin’s family of engines. The BE-7’s 40 kN (10,000 lbf) thrust is designed for large lunar payload transport. The engine’s propellants are a highly-efficient combination of liquid oxygen and liquid hydrogen. The BE-7 will have its first hotfire this summer. The engine will be available for sale to other companies for use in in-space and lander applications.


Quantum Computing for Everyone

Quantum Computing for Everyone

Chris Bernhardt

An accessible introduction to an exciting new area in computation, explaining such topics as qubits, entanglement, and quantum teleportation for the general reader.

Quantum computing is a beautiful fusion of quantum physics and computer science, incorporating some of the most stunning ideas from twentieth-century physics into an entirely new way of thinking about computation. In this book, Chris Bernhardt offers an introduction to quantum computing that is accessible to anyone who is comfortable with high school mathematics. He explains qubits, entanglement, quantum teleportation, quantum algorithms, and other quantum-related topics as clearly as possible for the general reader. Bernhardt, a mathematician himself, simplifies the mathematics as much as he can and provides elementary examples that illustrate both how the math works and what it means.

Bernhardt introduces the basic unit of quantum computing, the qubit, and explains how the qubit can be measured; discusses entanglement—which, he says, is easier to describe mathematically than verbally—and what it means when two qubits are entangled (citing Einstein’s characterization of what happens when the measurement of one entangled qubit affects the second as “spooky action at a distance”); and introduces quantum cryptography. He recaps standard topics in classical computing—bits, gates, and logic—and describes Edward Fredkin’s ingenious billiard ball computer. He defines quantum gates, considers the speed of quantum algorithms, and describes the building of quantum computers. By the end of the book, readers understand that quantum computing and classical computing are not two distinct disciplines, and that quantum computing is the fundamental form of computing. The basic unit of computation is the qubit, not the bit.