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There may be 300 million habitable planets in our galaxy
A new study from NASA and the SETI Institute comes up with an exciting number of potentially life-supporting planets.

Kepler-186f illustration
- A study analyzes data from the Kepler Space Telescope and the European Space Agency's GAIA survey to estimate the number of habitable planets.
- There may be 30 such planets in our own galactic neighborhood.
- The new estimate may help inform future research and missions.
Throughout its nine-year tour of duty that concluded in 2018, NASA's Kepler Space Telescope produced a massive amount of observational data. Scientists are still going through it all. Among its revelations were now-confirmed 2,800 exoplanets, with thousands more still being analyzed. A new study of its data suggests that there may be as many as 300 million inhabitable planets in our galaxy. It finds that several of these could be relatively close by, within 30 light years from here.
Co-author Jeff Coughlin stated in a SETI press release that "this is the first time that all of the pieces have been put together to provide a reliable measurement of the number of potentially habitable planets in the galaxy."
(We previously wrote about a specially designed calculator that determined there could be exactly 36 contactable civilizations.)
The research, a collaboration between NASA, SETI, and other organizations, will be published in The Astronomical Journal — you can see the pre-press version at arxiv.org.
What the study finds
Illustration of Kepler-7
Credit: SETI
The team that produced the new report was led by Steve Bryson of NASA's Ames Research Center in California. The authors of the study looked for stars that are similar in size, age, and temperature to our Sun, between 4,527 to 6,027 °C. These stars are either G dwarfs, or slightly smaller and more plentiful K dwarfs. Next, they looked for planets orbiting such stars that ranged in size from 0.5 to 1.5 times the size of Earth on the assumption that they were most likely to be rocky planets like ours.
A big factor affecting habitability is the ability to support surface water. Earlier estimates of habitable planets have focused primarily on an exoplanet's distance from its sun, the so-called "habitable zone." The new research also takes into consideration the amount of light the planet receives from its sun as a factor in the likelihood of water. The authors of the study supplemented the Kepler data with spectroscopic measurements from the European Space Agency's GAIA survey of a billion stars in the Milky Way.
The stars can be dim enough that their habitable zones are close, causing any exoplanets there to be tidally locked, which means the same side always faces their sun. This makes the stripping off of their atmospheres more likely. One of the unknowns is the degree to which a planet's atmosphere impacts its ability to retain water, though, and for the current research, the authors presumed that atmosphere has a minimal effect on the likelihood of surface water.
Taking all this into consideration, the research "estimate with 95% confidence that, on average, the nearest HZ planet around G and K dwarfs is ∼6 pc away, and there are ∼ 4 HZ rocky planets around G and K dwarfs within 10 pc of the Sun." (pc is the abbreviation for parsec.)
The study offers both a conservative estimate of the number of habitable exoplanets orbiting their stars — 0.37 to 0.60 planets per star — and a more optimistic one: 0.58 to 0.88 per star. More than half of galaxy's suitable stars may have habitable planets.
Refining a search
On a basic level, Coughlin notes, the study means "we're one step closer on the long road to finding out if we're alone in the cosmos."
The research may also prove useful in targeting future study and missions. Says Michelle Kunimoto of the Transiting Exoplanet Survey Satellite group at MIT in Cambridge, Massachusetts, "Knowing how common different kinds of planets are is extremely valuable for the design of upcoming exoplanet-finding missions." She adds that "surveys aimed at small, potentially habitable planets around Sun-like stars will depend on results like these to maximize their chance of success."
- Astronomer calculates the odds of intelligent alien life emerging ... ›
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‘Designer baby’ book trilogy explores the moral dilemmas humans may soon create
How would the ability to genetically customize children change society? Sci-fi author Eugene Clark explores the future on our horizon in Volume I of the "Genetic Pressure" series.
- A new sci-fi book series called "Genetic Pressure" explores the scientific and moral implications of a world with a burgeoning designer baby industry.
- It's currently illegal to implant genetically edited human embryos in most nations, but designer babies may someday become widespread.
- While gene-editing technology could help humans eliminate genetic diseases, some in the scientific community fear it may also usher in a new era of eugenics.
Tribalism and discrimination
<p>One question the "Genetic Pressure" series explores: What would tribalism and discrimination look like in a world with designer babies? As designer babies grow up, they could be noticeably different from other people, potentially being smarter, more attractive and healthier. This could breed resentment between the groups—as it does in the series.</p><p>"[Designer babies] slowly find that 'everyone else,' and even their own parents, becomes less and less tolerable," author Eugene Clark told Big Think. "Meanwhile, everyone else slowly feels threatened by the designer babies."</p><p>For example, one character in the series who was born a designer baby faces discrimination and harassment from "normal people"—they call her "soulless" and say she was "made in a factory," a "consumer product." </p><p>Would such divisions emerge in the real world? The answer may depend on who's able to afford designer baby services. If it's only the ultra-wealthy, then it's easy to imagine how being a designer baby could be seen by society as a kind of hyper-privilege, which designer babies would have to reckon with. </p><p>Even if people from all socioeconomic backgrounds can someday afford designer babies, people born designer babies may struggle with tough existential questions: Can they ever take full credit for things they achieve, or were they born with an unfair advantage? To what extent should they spend their lives helping the less fortunate? </p>Sexuality dilemmas
<p>Sexuality presents another set of thorny questions. If a designer baby industry someday allows people to optimize humans for attractiveness, designer babies could grow up to find themselves surrounded by ultra-attractive people. That may not sound like a big problem.</p><p>But consider that, if designer babies someday become the standard way to have children, there'd necessarily be a years-long gap in which only some people are having designer babies. Meanwhile, the rest of society would be having children the old-fashioned way. So, in terms of attractiveness, society could see increasingly apparent disparities in physical appearances between the two groups. "Normal people" could begin to seem increasingly ugly.</p><p>But ultra-attractive people who were born designer babies could face problems, too. One could be the loss of body image. </p><p>When designer babies grow up in the "Genetic Pressure" series, men look like all the other men, and women look like all the other women. This homogeneity of physical appearance occurs because parents of designer babies start following trends, all choosing similar traits for their children: tall, athletic build, olive skin, etc. </p><p>Sure, facial traits remain relatively unique, but everyone's more or less equally attractive. And this causes strange changes to sexual preferences.</p><p>"In a society of sexual equals, they start looking for other differentiators," he said, noting that violet-colored eyes become a rare trait that genetically engineered humans find especially attractive in the series.</p><p>But what about sexual relationships between genetically engineered humans and "normal" people? In the "Genetic Pressure" series, many "normal" people want to have kids with (or at least have sex with) genetically engineered humans. But a minority of engineered humans oppose breeding with "normal" people, and this leads to an ideology that considers engineered humans to be racially supreme. </p>Regulating designer babies
<p>On a policy level, there are many open questions about how governments might legislate a world with designer babies. But it's not totally new territory, considering the West's dark history of eugenics experiments.</p><p>In the 20th century, the U.S. conducted multiple eugenics programs, including immigration restrictions based on genetic inferiority and forced sterilizations. In 1927, for example, the Supreme Court ruled that forcibly sterilizing the mentally handicapped didn't violate the Constitution. Supreme Court Justice Oliver Wendall Holmes wrote, "… three generations of imbeciles are enough." </p><p>After the Holocaust, eugenics programs became increasingly taboo and regulated in the U.S. (though some states continued forced sterilizations <a href="https://www.uvm.edu/~lkaelber/eugenics/" target="_blank">into the 1970s</a>). In recent years, some policymakers and scientists have expressed concerns about how gene-editing technologies could reanimate the eugenics nightmares of the 20th century. </p><p>Currently, the U.S. doesn't explicitly ban human germline genetic editing on the federal level, but a combination of laws effectively render it <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">illegal to implant a genetically modified embryo</a>. Part of the reason is that scientists still aren't sure of the unintended consequences of new gene-editing technologies. </p><p>But there are also concerns that these technologies could usher in a new era of eugenics. After all, the function of a designer baby industry, like the one in the "Genetic Pressure" series, wouldn't necessarily be limited to eliminating genetic diseases; it could also work to increase the occurrence of "desirable" traits. </p><p>If the industry did that, it'd effectively signal that the <em>opposites of those traits are undesirable. </em>As the International Bioethics Committee <a href="https://academic.oup.com/jlb/advance-article/doi/10.1093/jlb/lsaa006/5841599#204481018" target="_blank" rel="noopener noreferrer">wrote</a>, this would "jeopardize the inherent and therefore equal dignity of all human beings and renew eugenics, disguised as the fulfillment of the wish for a better, improved life."</p><p><em>"Genetic Pressure Volume I: Baby Steps"</em><em> by Eugene Clark is <a href="http://bigth.ink/38VhJn3" target="_blank">available now.</a></em></p>The mystery of the Bermuda Triangle may finally be solved
Meteorologists propose a stunning new explanation for the mysterious events in the Bermuda Triangle.
One of life's great mysteries, the Bermuda Triangle might have finally found an explanation. This strange region, that lies in the North Atlantic Ocean between Bermuda, Miami and San Juan, Puerto Rico, has been the presumed cause of dozens and dozens of mind-boggling disappearances of ships and planes.
Astrophysicists find unique "hot Jupiter" planet without clouds
A unique exoplanet without clouds or haze was found by astrophysicists from Harvard and Smithsonian.
Illustration of WASP-62b, the Jupiter-like planet without clouds or haze in its atmosphere.
- Astronomers from Harvard and Smithsonian find a very rare "hot Jupiter" exoplanet without clouds or haze.
- Such planets were formed differently from others and offer unique research opportunities.
- Only one other such exoplanet was found previously.
Munazza Alam – a graduate student at the Center for Astrophysics | Harvard & Smithsonian.
Credit: Jackie Faherty
Jupiter's Colorful Cloud Bands Studied by Spacecraft
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="8a72dfe5b407b584cf867852c36211dc"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/GzUzCesfVuw?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>Lair of giant predator worms from 20 million years ago found
Scientists discover burrows of giant predator worms that lived on the seafloor 20 million years ago.
Bobbit worm (Eunice aphroditois)
- Scientists in Taiwan find the lair of giant predator worms that inhabited the seafloor 20 million years ago.
- The worm is possibly related to the modern bobbit worm (Eunice aphroditois).
- The creatures can reach several meters in length and famously ambush their pray.
A three-dimensional model of the feeding behavior of Bobbit worms and the proposed formation of Pennichnus formosae.
Credit: Scientific Reports
Beware the Bobbit Worm!
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="1f9918e77851242c91382369581d3aac"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/_As1pHhyDHY?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>FOSTA-SESTA: Have controversial sex trafficking acts done more harm than good?
The idea behind the law was simple: make it more difficult for online sex traffickers to find victims.
