Are skin tags contagious

Skin tags are a debatable issue, but it is certain that it is not contagious. Before you dwell on the debate on whether such tags are contagious or not, you should know what skin tag is.

To be more precise, you should understand how it is formed on the skin’s surface?

How it is formed

They are just excessive skin. It is not a matter of getting infected from someone. You don’t get excess skin just be getting infected.

It is formed because of the collagens and blood vessels concentrating on one part of the skin. The process swells the skins and thus, they are formed.

Why it is not contagious

Medical experts have conducted many experiments over the years on whether they could be contagious on any given point. The answer has always been no.

The reason why research scientists have come to the conclusion that they cannot be contagious by any means is the lack of virus element in its formation.

Virus does not spread any infection from the already formed skin rashes to other bodies. In fact, virus doesn’t have a role to play in those tags.

Though, few studies had showed that virus could play a role in its formation, but nothing concrete had cropped up from anywhere.

Scientists still maintain that the tags are virus free.

However, warts, unlike skin tags, which look more or less like it, are contiguous. It is spread to other bodies through HPV virus, but HPV has no role to play in them.

The best example of them being not contagious could be seen from the genital skin rashes. Sexual intercourse with a person with genital skin tags have never resulted in transmission of disease.

Therefore, it is simply a thrust of skin, and nothing else.

Weekly Q & A Home Gym for Beginners

Weekly Q & A: What do you have in your home gym?  What do you recommend for a beginner?

First, I want to congratulate you on taking the first step to working out at home and getting in shape.  Working out at home is convenient and affordable.  Not only was I self-conscience about my weight but the gym daycare’s policy is not to watch children under one year old.  Basically I had no choice but to workout at home and it is still my preferred method.

I already had a few things in my gym before I expanded it to include the other things I mention here.  My husband is in amazing shape.  He works out regularly and can eat anything he wants without gaining a pound.  Oops, a hint of jealousy just slipped out.

Well he started adding to our home gym when I was pregnant with our three year old.  He added a few sets of free weights (30 and 35 pounds), kickboxing pads and gloves, and a weight vest. Occasionally we will spare and I will use the weight vest to increase the challenge of my squats and lunges.

I had two sets of free weights already – 8 and 12 pounds – but I grew out of them quickly.  When I was able to add more things to my home gym, I added some 15 and 20 pound free weights.  I like these.

I already had a yoga mat, stability ball, and a few random things.  I added a resistance band but I didn’t like it because it stretched out too much.  I bought this one instead in red and I love it.  I added a 15 pound kettlebell that I love but is too light for me now and a 10 pound medicine ball.  

Do you need all of this stuff to start working out?  Absolutely not!!  I would encourage you to start with body weight exercises like squats, lunges, pushups, etc. 

However, if you are able to get just one thing, I would recommend some free weights.  Lifting weights is important because it causes your body to work (burning calories) in order to repair what you did during your weight lifting sessions.  You don’t want to get anything too heavy but you want to get something challenging.
I would recommend beginners start with 8 to 10 pounds for upper body exercises and for lower body exercises anything 15 pounds and up would be good.  Remember you want to challenge your body so do not go too light because you will not get the results you are looking for.

You can add other stuff later if you want.  Remember you don’t need anything for HIIT and you can modify other exercises that require other equipment.

You don’t need to spend a lot of money to work out at home.

Would you recommend something else for a home gym?  What do you absolutely love?

The Acai Berry Revolution

Today, the Acai Berry (pronounced AH-SIGH-EE) has completely TAKEN OVER the wellness industry by storm and created it’s own revolution. You probably find that funny because up until two years ago no one had heard of it. Today, there are hundreds of acai based products available on the market ranging from smoothies, juices, yogurts, and many varieties of supplements. You may have seen this remarkable fruit being showcased on the Oprah Winfrey show, Rachel Ray, multiple news broadcasts, the internet, and most recently the CBS show “The Doctors.”

So, just what is all the hype? acai berry

These little black berries are about the size of a blueberry and originate from deep in the midst’s of the the Amazon rainforest where you can find about a third of the herbs and natural substances used in modern medicine today.

Acai berries, grown on acai palm trees, are considered to be one of the worlds top “super foods” as they are extremely rich in minerals, vitamins, essential fatty acids, fiber, omega-3 fats, and antioxidants.

Before being exported to North America, Amazonian’s have been consuming this product for centuries reaping the benefits of better health and improved vitality. Researchers have recorded astronomical antioxidant properties and unheard of nutritional contents. The acai berry has one of the highest ORAC (Oxygen Radical Absorption Capacity) scores of any fruit on the planet which if you don’t know is good because it protects us from free radicals that put our health at risk.

We all know that a diet high in antioxidants is good for our health and can help protect our bodies from free radical damage and chronic disease. However, less that 20% of US adults consume the recommended amount of 5-9 servings of fruits a day. Most get less than one serving per day! Yikes! So, adding supplements such as antioxidant juices, especially those with acai included, can really help us increase our bodies ability to fight disease.

Acai berries are very small, 90% seed and 10% fruit, which is why so many of the products available are quite costly. Not only does it take a lot of berries to make an acai product but the preservation costs are astronomical, especially the best–the freeze drying process. The acai berry once harvested from the acai palms begin to lose their nutritional properties as quickly as 24 hours! Numerous tests have concluded that freeze-drying these berries best preserves the highest amount of nutrients. There are very few companies that actually use this form of preservation and only one that I know I trust and find reputable.

Acai juices are the best way to increase your fruit and vegetable intake each day. Protect yourself from disease and illness by consuming quality products high in antioxidants.

In a recent study conducted by the University of Florida, researchers found that 35-85% of human cancer cells were destroyed when exposed to the acai berry. Of course, this is just an preliminary study but one that is very positive and filled with hope. There are hundreds of studies being conducted to learn more about this amazing new Amazonian fruit. I am anxious to continue to learn more as they published.

Adding acai into your daily regime is something that I strongly recommend for better health and disease prevention. If you want my honest opinion about the best acai berry product on the market now, contact me and I would be happy to give you my recommendation for the best acai products.

Where did the Moon come from?

By J. Richard Gott

The standard theory for the origin of the Moon is that a Mars-sized planet (named Theia) collided with the Earth about 4.5 billion years ago, and that the splash debris formed the Moon.  This theory can explain why the Earth and Moon have identical oxygen isotope abundances (as discovered by the Apollo astronauts) while being so different in iron.  The Earth is about 30% iron by weight while the Moon is about 3%.  Collision simulations by   Robin Canup show that Theia must have hit the Earth when it was about 95% formed.  Thus there had been time for the iron in both Earth and Theia to sink to form iron cores.  The Canup simulations show that the splash material that formed the Moon comes from mostly Theia mantle material poor in iron.  But there is a remaining mystery.  Why are the oxygen isotope abundances in the Earth and Moon identical?  That makes it look like they came from exactly the same position in the solar system, 1 Astronomical Unit (1 AU) away from the Sun.  Mars, which is farther away, has quite different oxygen isotope abundance ratios.  As the Earth grew by gravitational accretion of planetesimals we would expect it to have gobbled up material near 1 AU first, and the last thing to fall in, like a fully formed Theia, would seem likely to have come from halfway between us and Mars (or halfway between us and Venus).  But that scenario would give Theia quite different oxygen isotope abundance ratios.  Also the collision dynamics required to form the Moon require Theia to fall in at very low velocity, not from a very eccentric orbit.  Is there any place to form Theia at 1 AU from the Sun where it would not be swept up by the Earth early-on before it had had time to grow?

Ed Belbruno and I wrote a paper saying there was such a place for Theia to originate, namely, either of the stable Lagrange points L4 or L5 in Earth’s orbit situated either 60 degrees ahead or behind the Earth as it circles the Sun.  Debris can accumulate in stable orbits at such Lagrange points.  Numerous Trojan asteroids are located at L4 and L5 in Jupiter’s orbit.  Belbruno and I proposed that Theia formed out of debris at either L4 or L5 in Earth orbit.

The Lagrange points in Earth’s orbit.  L1, L2, and L3 are unstable equilibria.  Objects can be placed there (like the WMAP satellite at L2, or the SOHO satellite at L1) but will eventually drift away.  L4 and L5 by contrast are stable.  Objects can circulate around L4 or L5 and remain stable indefinitely.  Belbruno and Gott propose that the giant impactor Theia originated from debris at either L4 or L5.  Gravitational perturbations by other planetesimals then sent Theia onto a horseshoe orbit that circulated through L5, L3, L4, and back again.  Finally it was perturbed onto a chaotic circulating orbit that sent it on a collision course with Earth.  


Theia would remain stable there and could grow large.  It would have the same oxygen isotope abundances as Earth because it was accreting material from exactly the same regions as Earth.  Eventually, we argued, perturbations by other remaining planetesimals knocked Theia out of L4 or L5 into an oscillating tadpole orbit, and then onto a horseshoe orbit that made close approaches to Earth.  Finally, we showed how it would be kicked out onto a chaotic, circulating orbit with a high probability of colliding with Earth, giving just the sort of low velocity collision that would be likely to form the Moon!

We found other examples of this phenomenon occurring in the solar system, which we pointed out in our 2005 Astronomical Journal paper.  Saturn’s Moon Tethys is accompanied by two Trojan moons in its orbit:  Telesto (leading) and Calypso (trailing), while Saturn’s moon Dione is also accompanied by two Trojan moons:  Helene (leading) and Polydeuces (trailing).  Saturn’s moon Janus has a moon Epimetheus co-orbiting with it in a horseshoe orbit, exactly like the horseshoe orbit that Belbruno and I had calculated for Theia to have been perturbed onto before its ultimate collision with Earth.  This analysis led us to a new theory for the origin of Saturn’s rings.  The standard theory was that Saturn’s rings were formed when an errant moon of Saturn’s wandered inside the Roche limit where tidal forces from Saturn ripped it apart and formed the rings.  But all the icy moons of Saturn out to Titan are in nice well-behaved circular orbits.  We argue that Saturn’s rings (made of icy particles) were originally much larger, and that outside the Roche limit, gravitational accretion was able to form icy moons out of the ring debris.  Inside the Roche limit, tidal forces simply prevent the formation of large moons and we are left with the rings.  This implies that the rings are old, consistent with recent Cassini satellite data.

Belbruno and I pointed out that asteroid 2002AA29 follows a horseshoe orbit with respect to the Earth that looks just like the ones we found for objects that have escaped from L4 or L5.  Perhaps it was part of some primordial debris that originated at the other stable Lagrange point that Theia did not occupy.   In that case it would be expected to have the same amount of iron as Earth and the same oxygen isotope abundances as Earth, having formed also at 1 AU from the Sun.  That could be tested in a future space mission.  I reasoned that if there are asteroids out there with this primordial composition, there should be meteorites with this composition as well.  I have found that the EH (Enstatite chondrite) meteorites have about the same iron content as the Earth and have identical oxygen isotope abundances.  So it would be interesting to see if asteroid 2002AA29 has a spectrum that resembles EH meteorites.  If it did, that would support our theory.  Independently, M. Javoy has proposed that the Earth formed out of EH (Enstatite chondrite) material, so such an observation would support his theory as well.

People sometimes wonder if the Apollo missions to the Moon discovered anything important.  They did.  The oxygen isotope data they brought back led astronomers to our current theory for the origin of the Moon as formed by a giant impact from a Mars-sized object we now call Theia.  If the Apollo program allowed astronomers to figure out how the Moon was formed, what greater scientific accomplishment could one hope for!  Those same oxygen isotope abundance data also point toward an origin for Theia at 1 AU and, therefore, to an origin at one of Earth’s Lagrange points.  Theia would have appeared in the early Earth’s sky as either a morning or evening star stationed 60 degrees away from the sun.  Then, perturbed by other planetesimals, it would have started to move, eventually looming large.



Belbruno, E.; Gott, J. R. Where did the Moon come from? Astronomical Journal, Vol. 129, pp. 1724-1745 (2005).

Canup, R., Simulations of late lunar-forming impact, Icarus, Vol. 168, pp. 433-456 (2004).

Chown, Marcus. The planet that stalked the Earth. New Scientist, August 14, 2004, pp. 26-30.

Gott, J. R. Lagrange L4/L5 Points and the Origin of Our Moon and Saturn’s Moons and Rings. Annals of the New York Academy of Sciences, Vol. 1065, New Trends in Astrodynamics, pp. 325-335 (2005).

Javoy, M. The integral enstatite chondrite model of the earth.  Geophysical Research Letters, Vol. 22, pp. 2219-2222 (1995).

Vanderbei, R. J. Horsing Around on Saturn. In New Trends in Astrodynamics and Applications, Vol.1065, pp. 336-345. NY Academy of Sciences, 2005.


More information about J. Richard Gott’s new book is available at

 By J. Richard Gott

 J. Richard Gott is Professor of Astrophysics at Princeton University where he received his doctorate.  He is known for his work in cosmology and General Relativity.  He and his work have been profiled in Time, Newsweek, The New Yorker, National Geographic, and the New York Times.  In 1991 he discovered an exact solution to Einstein’s equations for the geometry around two moving cosmic strings, a solution of particular interest because it allows time travel to the past.  His measurement of the Sloan Great Wall of galaxies (1.37 billion light-years long) with Mario Juric was entered into the Guinness World Records 2006 as the “largest structure in the universe,” a record it still holds today.  His new book Sizing Up the Universe, co-authored with Robert Vanderbei includes his remarkable Map of the Universe, showing for the first time the entire visible universe in a single map.  The Los Angeles Times called it “arguably the most mind bending map to date.”

UFOs: Believe ‘em or Not?

Global warming. Species extinction. The end of fossil fuels. Without doubt, there are plenty of problems to cause you to sweat and fret if you’re concerned about our planet’s near-future. But how about adding this to your plate: alien invasion. Sure, it happens regularly in the movies, but what if it’s for real?

One-third of the populace thinks it is real. The exact fraction varies a bit, depending on when and where you do the surveys, but for the last half-century, roughly one in three Americans has given thumbs up to the idea that visitors from distant star systems are buzzing our country’s fruited plain – and occasionally plucking citizens from their bedrooms to perform unwholesome experiments on their bodies and their virtue. The percentage of people who believe this is the same in Canada, Australia and England.

Frankly, I’m skeptical that UFOs – or some fraction of them – are piloted by aliens. Mind you, as a SETI researcher I’m more than comfortable with the idea of a myriad other worlds frosted with intelligent beings. The latest results from NASA’s Kepler project suggest that at least a few percent of all stars have planets that, in principle, could boast liquid oceans and a thick atmosphere. That means there are billions of such worlds in our galaxy alone. It’s hard to imagine they’re all as sterile as autoclaves, or that none has evolved intelligent creatures. So I don’t argue against extraterrestrial visitors because I think we’re the only clever critters inhabiting the Milky Way.

No, my skepticism derives from two other lines of argument: (1) the unreasonableness of having alien visitors now, and (2) the weakness of the evidence.

Consider the first point, the matter of timing. Really, why have they chosen to pay a house call just at the moment when we can all watch it on Fox TV? The Earth has been around for 4.6 billion years, and there’s been life carpeting

the planet for at least three-fourths of that time. Homo sapiens have been strutting the landscape for a few hundred thousand years, or put another way, for ten thousand generations. 

So why are the aliens here now? How did we win the lottery?

The usual answer given by UFO proponents is that we’ve inadvertently prompted the aliens to visit. These beings are unhappy with our warlike ways or our environmental depredations – a motivation similar to what we’ve seen in the movie,“The Day the Earth Stood Still.” Mind you, I don’t see much evidence that the extraterrestrials have done anything to ameliorate either of these problems. But a far stronger point is that they don’t know about them! Our high-frequency, high-powered radio, television, and radar transmissions began around 1940. Even assuming that the extraterrestrials can travel at the speed of light, their home planet can’t be more than 4 light-years’ distant if we propose that they’ve picked up these signals, decided we are a danger to ourselves or our planet, and have come here in time to produce all the saucer sightings of the late 1940s.

But there are no stars within 4 light-years.

The only way to negate this argument is to assume that the aliens are always here (or nearly always). In that case – if our planet has had a constant extraterrestrial presence – then where’s the inevitable detritus of their existence? Where’s their garbage? Are we really to believe that a coterie of advanced beings has been sharing the planet with terrestrial life for thousands, millions, or billions of years, and not left anything lying around for the archaeologists (or the coal miners) to dig up?

That would be extraordinary. However, given that we’re talking about aliens, a lot of people are willing to accept the extraordinary. The extraterrestrials have warp drive, or time travel, or cloaking technology, or who-knows-what, they say. And true enough, the extraterrestrials can be as advanced, in theory, as we wish them to be. Consequently, arguments against visitation based on reasonable conclusions from physics are, in the end, unconvincing for the hard-core believers because – after all – we don’t know all of physics.
So in the end it comes down to this: what’s the evidence? Forget their motivations and their motive power. Just show me the proof.

Let’s be clear, tens of thousands of sightings of UFOs each year doesn’t do it for me. There were lots of sightings of leprechauns in Ireland, after all. Plenty of people claim to have espied bigfoot too, not to mention ghosts and angels. But in the end, most of that boils down to stories about what people have seen. And witness testimony is hardly convincing if you’re talking science (it’s not all that compelling in criminal trials either).

We should look at the physical evidence. But that’s thin on the ground. Where’s the stuff we could stack up in

museums, or haul off to academic research labs? If aliens really made a last-minute navigation error over Roswell, New Mexico in 1947, where are the bits and pieces of their craft? The usual rejoinder is that the government, in a rare display of efficiency, has scooped up all such evidence, and carted it away.

While the idea of a federal conspiracy to deny us access to Exhibit A in any UFO incident is appealing, it quickly becomes a so-called argument from ignorance. “Yes, there’s good evidence for alien craft, but it’s kept under wraps, and that’s why I can’t show it to you.” That’s not terribly persuasive.

The bottom line is that, despite at least 63 years of intense UFO reports, very few scientists seem to spend their time hunting for proof that we share our planet with alien houseguests. That’s not because it wouldn’t be an interesting phenomenon, if true. It’s only that – weighing the arguments and the evidence – they’ve voted with their research time and their grad students, and concluded that there’s very little likelihood that aliens are truly hanging out in the hood.

By Seth Shostak, Ph.D.

 Seth is the Senior Astronomer at the SETI Institute in Mountain View, California, and the 2004 winner of the Klumpke-Roberts Award awarded by the Astronomical Society of the Pacific in recognition of his outstanding contributions to the public understanding and appreciation of astronomy.

He hosts the SETI Institute’s radio program Are We Alone? Each week, Shostak interviews guests about the latest scientific research on a variety of topics: cosmology, physics, genetics, paleontology, evolutionary biology and astrobiology, and once a month hosts “Skeptic Check”, a show focused on debunking pseudo-science, U.F.O.s and practices such as astrology and dowsing. Are We Alone? is available for download at the SETI Institute’s website ,and through podcasts.

Shostak has been an observer for Project Phoenix (SETI) as well as an active participant in various international forums for SETI research. He is also Chair of the International Academy of Astronautics SETI Permanent Study Group.

Scientific Events that Most Changed the World—Survey Response by Dr. Seth Shostak

In your opinion, what are the five scientific events that changed the world the most?

 1. Publication of “Principia” by Isaac Newton

2. Copernicus publishes his work establishing the solar-centric cosmos

3. Neils Bohr proposes quantized states for the hydrogen atom

4. Albert Einstein publishes his work on Special Relativity

5. Darwin publishes “On the Origin of Species”

When Newton published his work on (classical) mechanics, he did two things of enormous importance: (1) he provided the analytic tools for analyzing and predicting the behavior of essentially all mechanical systems, from celestial to domestic, and (2) by so doing, he built the foundation of modern science, which seeks natural explanations for phenomena, and quantizes these explanations so that they have predictive power. This latter ability is what sets science apart from other endeavors — it not only tells you how something works, but will allow you to design something entirely new with confidence about how it WILL work.

By Seth Shostak, Ph.D.

 Seth is the Senior Astronomer at the SETI Institute in Mountain View, California, and the 2004 winner of the Klumpke-Roberts Award awarded by the Astronomical Society of the Pacific in recognition of his outstanding contributions to the public understanding and appreciation of astronomy.

He hosts the SETI Institute’s radio program Are We Alone? Each week, Shostak interviews guests about the latest scientific research on a variety of topics: cosmology, physics, genetics, paleontology, evolutionary biology and astrobiology, and once a month hosts “Skeptic Check”, a show focused on debunking pseudo-science, U.F.O.s and practices such as astrology and dowsing. Are We Alone? is available for download at the SETI Institute’s website ,and through podcasts.

Shostak has been an observer for Project Phoenix (SETI) as well as an active participant in various international forums for SETI research. He is also Chair of the International Academy of Astronautics SETI Permanent Study Group.

Nanorobots in Your Future

An exciting revolution in health care and medical technology looms large on the horizon.  Yet the agent of change is microscopically small, and will be made possible by nanotechnology.  Nanotechnology is the engineering of molecularly precise structures and, ultimately, molecular machines.  The prefix “nano-“ refers to the scale of these constructions.  A nanometer is one-billionth of a meter, the width of about 5 carbon atoms nestled side by side.  Nanomedicine is the application of nanotechnology to medicine.  The ultimate tool of nanomedicine is the medical nanorobot – a robot the size of a bacterium, composed of molecule-size parts somewhat resembling macroscale gears, bearings, and ratchets.

The first and most famous scientist to voice the possibility of nanorobots traveling through the body, searching out and clearing up diseases, was the late Nobel physicist Richard P. Feynman.  In his remarkably prescient 1959 talk “There’s Plenty of Room at the Bottom,” Feynman proposed employing machine tools to make smaller machine tools, these to be used in turn to make still smaller machine tools, and so on all the way down to the atomic level, noting that this is “a development which I think cannot be avoided.”

With these small machine tools in hand, small mechanical devices, including nanorobots, could be constructed.  This technology, said Feynman, “suggests a very interesting possibility for relatively small machines.  Although it is a very wild idea, it would be interesting in surgery if you could swallow the surgeon.  You put the mechanical surgeon inside the blood vessel and it goes into the heart and looks around.  (Of course the information has to be fed out.)  It finds out which valve is the faulty one and takes a little knife and slices it out.  …[Imagine] that we can manufacture an object that maneuvers at that level!…  Other small machines might be permanently incorporated in the body to assist some inadequately functioning organ.”

We cannot build such tiny robots today.  But perhaps by the late 2020s or early 2030s, we will.  These future devices may be made of rigid diamondoid nanometer-scale parts and subsystems including onboard sensors, motors, manipulators, and molecular computers.  They will be fabricated in a nanofactory via positional assembly:  picking and placing molecular parts one by one, then moving them along controlled trajectories much like the robot arms that manufacture cars on automobile assembly lines.  These steps are repeated over and over with all the different parts until the final product, such as a medical nanorobot, is fully assembled.

The ability to build nanorobots cheaply and in therapeutically useful numbers would revolutionize the practice of medicine.  Performance improvements up to 1000-fold over natural biological systems of similar function appear possible.  For example, the respirocyte is an artificial mechanical red blood cell just 1 micron in diameter having 1/100th the volume of a natural red cell.  Red cells carry oxygen to our tissues and remove carbon dioxide.  Respirocytes do too, but would be made of much stronger diamond-like materials, not floppy lipids and proteins as we find in living cells.  This allows respiratory gases to be safely stored within the respirocyte at tremendous pressures – up to 1000 atmospheres – and to be loaded or unloaded, molecule by molecule, using mechanical pumps on the device’s surface.  This simple nanorobot is regulated by onboard computers, powered by glucose fuel cells, and controlled by a physician who communicates with the device via ultrasound signals beamed into the body from outside.  A therapeutic 5-cc injection of respirocytes, just 1/1000th of total blood volume, duplicates the oxygen-carrying ability of the entire human blood mass and could instantly revive emergency victims of carbon monoxide poisoning at the scene of a fire.

Artificial mechanical white blood cells called microbivores are nanorobots that would seek and digest harmful bloodborne pathogens including bacteria, viruses, or fungi.  The pathogens are completely digested into harmless sugars, amino acids and the like, which are the only effluents from this 3-micron nanorobot.  No matter that a bacterium has acquired multiple drug resistance to antibiotics or to any other traditional treatment – the microbivore will eat it anyway.  Microbivores would completely clear even the most severe bloodborne infections in hours or less, then be removed from the body.  This is 1000 times faster than the weeks or months often needed for antibiotic-based cures.  Related medical nanorobots with enhanced tissue mobility could similarly consume tumor cells with unmatched speed and surgical precision, eliminating cancer.  Other devices could be programmed to remove circulatory obstructions in just minutes, quickly rescuing even the most compromised stroke victim from near-certain brain damage.

Nanorobots could perform surgery on individual cells.  In one procedure, a nanorobot called a chromallocyte, controlled by a physician, would extract existing chromosomes from a diseased cell and insert fresh new ones in their place.  This process is called chromosome replacement therapy.  The replacement chromosomes are manufactured earlier, outside of the patient’s body, by a desktop nanofactory that includes a molecular assembly line, using the patient’s individual genome as the blueprint.  If the patient chooses, inherited defective genes could be replaced with nondefective base-pair sequences, permanently curing any genetic disease and permitting cancerous cells to be reprogrammed to a healthy state.  Each chromallocyte is loaded with a single copy of the digitally-corrected chromosome set.  After injection, each device travels to its target tissue cell, enters the nucleus, replaces old worn-out genes with new chromosome copies, then exits the cell and is removed from the body.

The implications for extension of healthy lifespan are profound.  Perhaps most importantly, chromosome replacement therapy could be used to correct the accumulating genetic damage and mutations that leads to aging in every one of your cells.  With annual checkups and cleanouts, and some occasional major cellular repairs, your biological age could be restored once a year to a more or less constant physiological age that you select.  Nanomedicine thus may permit us first to arrest, and later to reverse, the biological effects of aging and most of the current medical causes of natural death, severing forever the link between calendar time and biological health.


Website References

1.  Personal website of Robert A. Freitas Jr.

2. Nanomedicine website

3.  Nanofactory Collaboration website

4.  Nanomedicine Art Gallery

Literature References (technical)

1.  First book on nanomedicine ever published:  Robert A. Freitas Jr., Nanomedicine, Volume I: Basic Capabilities, Landes Bioscience, Georgetown, TX, 1999.   URL:

2.  First medical nanorobot design paper ever published (respirocytes):  Robert A. Freitas Jr., “Exploratory Design in Medical Nanotechnology: A Mechanical Artificial Red Cell,” Artificial Cells, Blood Substitutes, and Immobil. Biotech. 26(1998):411-430.  URL:

3.  Published design paper on the microbivores:  Robert A. Freitas Jr., “Microbivores: Artificial Mechanical Phagocytes using Digest and Discharge Protocol,” J. Evol. Technol. 14(April 2005):55-106.

4.  First technical description of a cell repair nanorobot ever published:  Robert A. Freitas Jr., “The ideal gene delivery vector: chromallocytes, cell repair nanorobots for chromosome replacement therapy,” J. Evol. Technol. 16(June 2007):1-97.

5.  Survey book on self-replication:  Robert A. Freitas Jr., Ralph C. Merkle, Kinematic Self-Replicating Machines, Landes Bioscience, Georgetown, TX, 2004.  URL:

6.  Best survey of future nanorobot applications in medicine:  Robert A. Freitas Jr., “Chapter 23. Comprehensive Nanorobotic Control of Human Morbidity and Aging,” in Gregory M. Fahy, Michael D. West, L. Stephen Coles, and Steven B. Harris, eds, The Future of Aging: Pathways to Human Life Extension, Springer, New York, 2010, pp. 685-805.

Literature References (popular)

1.  Robert A. Freitas Jr., “Say Ah!” The Sciences 40(July/August 2000):26-31.  URL:

2.  Robert A. Freitas Jr., “Death is an Outrage!” Invited Lecture delivered at the Fifth Alcor Conference on Extreme Life Extension, 16 November 2002, Newport Beach, CA.  URL:

3.  Robert A. Freitas Jr., “Nanomedicine,”, 17 November 2003.  URL:

 © 2011 Robert A. Freitas Jr.  All Rights Reserved.

 By Robert A. Freitas Jr., J.D.

 Robert A. Freitas Jr. is Senior Research Fellow at the Institute for Molecular Manufacturing (IMM) in Palo Alto, California, and was a Research Scientist at Zyvex Corp. (Richardson, Texas), the first molecular nanotechnology company, during 2000-2004.  He received B.S. degrees in Physics and Psychology from Harvey Mudd College in 1974 and a J.D. from University of Santa Clara in 1979.  Freitas co-edited the 1980 NASA feasibility analysis of self-replicating space factories and in 1996 authored the first detailed technical design study of a medical nanorobot ever published in a peer-reviewed mainstream biomedical journal. Freitas is the author of Nanomedicine, the first book-length technical discussion of the potential medical applications of molecular nanotechnology;  the initial two volumes of this 4-volume series were published in 1999 and 2003 by Landes Bioscience.  His research interests include:  nanomedicine, medical nanorobotics design, molecular machine systems, diamondoid mechanosynthesis (theory and experimental pathways), molecular assemblers and nanofactories, atomically precise manufacturing, and self-replication in machine and factory systems.  He has published 49 refereed journal publications and contributed book chapters, co-authored Kinematic Self-Replicating Machines (Landes Bioscience, 2004), and in 2006 co-founded the Nanofactory Collaboration.  He won the 2009 Feynman Prize in nanotechnology for theory, the 2007 Foresight Prize in Communication, and the 2006 Guardian Award from Lifeboat Foundation.  He wrote the first two U.S. patents ever filed on diamond mechanosynthesis (the first of which was awarded on 30 March 2010) and serves on the Editorial Boards of 9 medical or nanotech journals.  His home page is

Hunting for ET

It is an impressive fact, and one that would have astounded your grandparents, but astronomers now estimate that our home galaxy – the Milky Way – sports at least a trillion planets. That’s a number not easy to picture, a tally greater than the number of trees in the United States.

Most of those unseen worlds are undoubtedly like some of the loser locales of our own solar system – airless and dry worlds like Mercury, or fetid balls of gas like Jupiter. In other words, most of the trillion planets infesting our galactic home are likely to be sterile, and dead as stone.

But just as there are winners lurking in a trillion lottery tickets, so too is it likely that among the manifold orbs of the Milky Way are winning worlds – planetary cousins of Earth. There could be millions, perhaps billions of planets or moons sporting thick atmospheres and liquid, water-filled oceans. If a fraction of these has cooked up life – or better yet, intelligent life – we are surrounded by a great deal of cosmic company.

In other words, what most of the public already believes – that alien societies pepper the universe – now seems at least plausible on the basis of hard science.

How might we find these other civilizations? Despite the impression conveyed by movies and TV, we can’t go there. Our rockets aren’t nearly speedy enough to be practical for interstellar travel. Even the fastest NASA spacecraft would take more than 100 thousand years just to reach Alpha Centauri, the nearest star to us other than the Sun (and also, incidentally, the stellar neighborhood of the large moon Pandora, the setting of James Cameron’s latest film, Avatar.)

So we’re not going to discover the aliens by visiting them. And while one-third of the American public believes that extraterrestrials are visiting us, few scientists think that the evidence for planetary house guests is convincing.

But there’s another way to get in touch. Rather than count on a face-to-face hookup, we could hunt for evidence of extraterrestrial beings that reaches us on a light beam or a radio wave – proof of alien intelligence that travels to Earth at the speed of light. Just as our radar and TV transmitters loft kilowatts of signal into space, so too might distant civilizations make their presence known by a faint radio whine picked up from light-years away.

Attempting to eavesdrop on alien signals is an enterprise that’s exactly 50 years old this month. In April, 1960 astronomer Frank Drake used an 85 foot radio antenna in West Virginia in the first SETI experiment (SETI being the acronym for the Search for Extraterrestrial Intelligence). Drake examined two nearby star systems for radio emissions without hearing anything that was obviously extraterrestrial. And in the 50 years since his effort, we still haven’t picked up any radio chatter from galactic neighbors.

But that’s no reason to get discouraged. The march of technology (primarily improvements in the speed of digital electronics) has made today’s SETI experiments far speedier at checking out star systems over wide swaths of the radio dial than was possible during Drake’s pioneering search. SETI has been likened to searching for a needle in a haystack, but today’s equipment has upped the speed of hay reconnaissance by trillions of times.

The latest wrinkle in the SETI game is the construction of large radio antennas (usually called radio telescopes) that are designed from the get-go for signal searching. The SETI Institute, located in California’s Silicon Valley, has joined up with the University of California at Berkeley to construct such an instrument. It’s called the Allen Telescope Array, because the initial funding was provided by entrepreneur Paul Allen. At the moment, the ATA comprises 42 antennas, each large enough (20 feet in diameter) to thoroughly dismay your neighbors if set down in the backyard. The Array is located in California’s Cascade mountains, about 300 miles north of San Francisco – a rural, topographically rugged area which provides both shielding from the transmitters of the big cities, and freedom from all the electrical noise one finds in an urban setting. There are no cell phone towers for miles.

So what’s the future? In the next two dozen years, powerful instruments such as this new array will allow the scrutiny of a million nearby star systems or more, in a search for faint, deliberately broadcast signals. If there are tens of thousands of alien societies spread throughout the Milky Way, then sampling a million stars could produce a hit.

If that happens, if we find someone out there at least as clever as we are, would that cause panic or the disruption of our own civilization? Hardly. After all, these aliens would be hundreds or thousands of light-years distant – which means that neither conversation nor rendezvous would be practical.

But a SETI success would tell us something very interesting. Namely, that what’s happened here on Earth is not some sort of one-off event, but simply an example of a process that’s taken place on a myriad of worlds. It would tell us that life – even intelligent life – is not a cosmic miracle, but merely a cosmic infection.

About Author Seth Shostak, Ph.D. :

Seth is the Senior Astronomer at the SETI Institute in Mountain View, California, and the 2004 winner of the Klumpke-Roberts Award awarded by the Astronomical Society of the Pacific in recognition of his outstanding contributions to the public understanding and appreciation of astronomy.

He hosts the SETI Institute’s radio program Are We Alone? Each week, Shostak interviews guests about the latest scientific research on a variety of topics: cosmology, physics, genetics, paleontology, evolutionary biology and astrobiology, and once a month hosts “Skeptic Check”, a show focused on debunking pseudo-science, U.F.O.s and practices such as astrology and dowsing. Are We Alone? is available for download at the SETI Institute’s website ,and through podcasts.

Shostak has been an observer for Project Phoenix (SETI) as well as an active participant in various international forums for SETI research. He is also Chair of the International Academy of Astronautics SETI Permanent Study Group.