Month: July 2021

In the past ten years, the discovery of extrasolar planets has accelerated immensely. So far, 4,424 exoplanets have been confirmed in 3,280 star systems, and a further 7,453 are awaiting confirmation. Previously, most of these planets were gas giants, with about 66% similar to Jupiter or Neptune, while another 30% were giant rock planets (also known as “super-earths”). Only a small fraction of confirmed exoplanets (less than 4%) are similar in size to Earth.

However, according to new research from astronomers working at NASA Ames Research Center, it is possible that Earth-sized exoplanets are more abundant than previously thought. As they showed in a recent study, there could be twice as many rocky exoplanets in binary star systems that are obscured by the glare of their parent stars. These findings could have a drastic impact on the search for potentially habitable worlds, since about half of all stars are binary systems.

For their study, the research team examined 517 stars harboring exoplanets identified by NASA’s Transiting Exoplanet Survey Satellite (TESS) during its three-year period of operation. When compared with data from the twin telescopes at the Gemini International Observatory and the WIYN 3.5-meter telescope at the Kitt Peak National Observatory, they found that over 100 of these stars likely had a binary companion.

Artist’s impression of the Transiting Exoplanet Survey Satellite (TESS). Photo credit: NASA’s Goddard Space Flight Center

The paper describing their results was accepted for publication in the Astronomical Journal. Dr. Kathryn Lester, a postdoctoral fellow at NASA Ames Research Center, led the research effort with support from colleagues from NASA Ames, the US Naval Observatory, NASA Exoplanet Science Institute, NSF’s National Optical-Infrared Astronomy Research Laboratory (NOIRLab). , the Lowell Observatory, and Georgia State and Standford Universities.

The problem with transits

To date, the vast majority of confirmed exoplanets (approx. 75%) have been discovered using the transit method (also known as transit photometry). This consists of observing stars for periodic drops in brightness that may be the result of a planet passing (transiting) in front of their face relative to the observer. Like its predecessor Kepler, TESS relies on the transit method to determine the presence of exoplanet systems around thousands of stars at any given point in time.

Unfortunately, binary companions have always been a challenge when it comes to spotting exoplanets in transit. Transit photometry requires star systems to be observed from the edge so that exoplanets can be discovered. But in binary star systems in which two stars orbit each other, there are regular drops in brightness and are the result of the eclipse of a companion.

As a result, it can be very difficult to spot smaller exoplanets orbiting closer to their stars, where astronomers expect to find rocky planets in the stars’ Circumolar Habitable Zone (HZ). Instead, using the transit method with binary star systems will likely only reveal gas giants and / or planets that have distant orbits from their parent stars. For this reason, Dr. Lester and her colleagues are figuring out whether some of the stars that host the exoplanet were actually binary stars.

In search of stellar companions

The team relied on a technique called speckle imaging, which combines large numbers of short exposure images and analyzes them to greatly improve the resolution of ground-based telescopes (similar to interferometry). Of the 517 TESS Objects of Interest (TOIs) they examined, they found that 73 exoplanet host stars that had previously appeared as a single point of light actually had a stellar companion.

They also found that 29 TOI stars that had generated false positive results in the past also had stellar companions. Dr. Lester recently said in a press release from NOIRLab:

“With the 8.1-meter telescopes at the Gemini Observatory, we received extremely high-resolution images of exoplanet host stars and discovered stellar companions at very small distances … Since around 50% of the stars are in binary systems, we could discover – and the chance to study – many earth-like planets. “

The next step was to compare the exoplanets discovered in these systems with the sizes of the exoplanets discovered in single star systems. From this, the team was able to show that the TESS space probe was able to identify both Jupiter and Neptune-like (“large”) exoplanets as well as super-earths and Earth-like (“small”) exoplanets that orbit individual stars only large planets in binary star systems.

These results suggest that there may be a population of Earth-sized exoplanets in binary systems that have gone undetected by missions such as TESS, Kepler, and other exoplanet surveys based on transit photometry. Scientists have suspected for some time that small planets in binary star systems are missing during transit surveys because of possible interference from a companion star.

However, this new study provides the first observational support for this suspicion while also showing what type of exoplanets are affected. It is also important because the transit method has so far been considered to be the most effective means of detecting exoplanets – it accounts for 3343 of the 4424 confirmed exoplanets. But if these results are correct, there could be up to 1,600 rocky exoplanets that have been missed during transit surveys.

This means that in the future, astronomers will have to rely on a variety of observation techniques before they can conclude that a binary system has no Earth-like planets. Like Dr. Lester said:

“With around 50% of the stars in binary systems, we could miss the discovery – and the chance to study many Earth-like planets. Astronomers need to know whether a star is a single or a binary star before claiming that no small planets exist in this system. If it is a single one, it could be said that there are no small planets. But when the host is in a binary star, you don’t know if a small planet is obscured by the companion star or does not exist at all. To find out, one would need more observations with a different technique. “

“We have shown that it is more difficult to find Earth-sized planets in binary star systems because small planets are lost in the light of their two parent stars,” added Dr. Steve Howell, director of speckle imaging work at NASA Ames, added a co-author on paper. “Your transits are ‘filled in’ by the light of the companion star. This is an important finding in the exoplanet work. The results will help theorists to create their models for the formation and evolution of planets in binary star systems. “

An illustration of the Kepler-47 circumbinary planetary system. Photo credit: NASA / JPL Caltech / T. Pyle

Another aspect of the study was that Dr. Lester and her colleagues analyzed the distance between binary companions in systems in which TESS discovered large planets. They found that pairs that host exoplanets are typically further apart than binary pairs that do not know any exoplanets. This could be interpreted as an indication that no planets form around stars that have nearby stellar companions.

In the future, this could be used to put additional restrictions on where astronomers should look for rocky planets. Dr. Lester and her team’s speckle imaging study also illustrates how exoplanet studies move from exoplanet discovery to characterization. In addition to characterizing the atmospheres and surface environments of exoplanets, there is also the crucial task of characterizing planetary systems.

By knowing which types of stars are most likely to support rocky exoplanets, astronomers and astrobiologists can narrow down their search for planets that are best suited for “life as we know it.”

Further reading: NOIR Lab

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By Larry Behrens
July 06, 2021

As President Biden continues to advance his environmental agenda with his attacks on American oil and gas workers, it is high time to shed some light on the failures he advocated. He may claim that his proposal to produce 80% of American electricity from carbon-free sources is a bold new idea, it’s actually a green failure that he’s trying to recycle … and we have the receipts from two states to do so to prove.

Let me introduce you to California and Arizona, two neighboring states, one of which has accepted the Biden Green Plan for years while the other has rejected it. Rest assured, Biden, John Kerry, and their army of eco-warriors hope you are ignoring these uncomfortable truths.

In November 2018, Arizona voters beat Prop 127 by a margin of more than 2 to 1. The electoral measure was heavily promoted by former presidential candidate, current extreme eco-left billionaire Tom Steyer. Similar to Biden’s plan, Prop 127 required that Arizona get 50 percent of its electricity from “renewable” sources by 2030. Remember, these are the same voters who elect a Democrat in the US Senate and fair Biden’s votes. two years later the race for the presidency tipped to the left. In other words, Prop 127, less restrictive than the Biden Plan, turned out to be too extreme for voters in the center

While 70 percent of Arizonans opposed the (future) Biden plan, California lawmakers passed SB 100, which enforced a renewable standard of 60 percent by 2030.

The very different results speak for themselves.

Working families in California were at the end of blackouts in August 2020 as temperatures hit triple digits in some areas. These blackouts, the first in nearly 20 decades, may not be the last as regulators warn that the Golden State could “go out” in the summer of 2021 as well.

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At the same time as California’s families were battling electricity to stay cool, Phoenix residents had to endure temperatures in excess of 110 degrees for 50 days in a row. Still, families were able to stay cool because Arizona gets most of its energy from natural gas and nuclear power. Both sources are banned under California’s radical plan. Voters rejected the Biden Plan and not only did power flow on, but their wallets did not suffer. Lower energy costs and no power outages are the result in Arizona.

California’s families are already paying some of the highest eclectic tariffs in the country, but the price of electricity has soared nearly 11 percent in the last year alone. So, while the people of California dodged rolling blackouts, they also paid an ever-increasing premium for adopting the Biden Plan.

For the record, the average Arizona electric bill rose just 0.1 percent over the same period.

Unfortunately, these terrible results are just the beginning. Today California is able to sidestep some of the worst effects of its dire decisions because its leaders import 25 percent of all its electricity from other states, including places that, as you guessed, produce that electricity from carbon-based sources. You shouldn’t be surprised to learn that one of the states selling power to California is … Arizona.

If the US adopts the California / Biden Plan, there will be no substitute state for us to import our electricity. There are only high prices, rolling blackouts and empty promises. These are the only real sources of power in the Biden Plan.

Larry Behrens is the author of the report “Lights Out: How Green Mandates Are Undermining the Affordability and Reliability of Electricity”. He currently works as the Western States Director for Power The Future, an organization that fights for America’s energy workers. He was previously the communications director for New Mexico Governor Susana Martinez. You can find him on Twitter at @larrybehrens

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A close pass by Comet Wirtanen in 2018 offered researchers an unprecedented opportunity.

Comets are full of surprises. Not only do they often perform below or occasionally above expectations, but they also offer a glimpse of what remains of the very early solar system. In December 2018, astronomers had the unprecedented opportunity to study one of these relics of the early solar system up close when Comet 46P / Wirtanen passed Earth only 30 times the Earth-Moon distance (7.1 million miles away ) flew by in the century.

The orbit of comet 46P / Wirtanen. NASA / JPL

The short-period comet 46P Wirtanen was discovered in 1948 by the astronomer Carl A. Wirtanen and orbits the Sun every 5.4 years on an orbit that takes it from a perihelion of 1.06 AU from the Sun to an aphelion of 5.13 AU directly outside of the perihelion of Jupiter.

The 2018 approach to Earth was particularly favorable for the comet, and this time astronomers at the WM Keck Observatory in Maunakea, Hawaii were ready. Keck’s near-infrared spectrograph (NIRSPEC) just received a major upgrade with more pixels and higher sensitivity, an upgrade that would receive the comet’s first light spectra.

Instruments also need hugs. Dr. Emily Martin with the newly upgraded NIRSPEC instrument. WM-Keck Observatory.

And the results recently published in the Planetary Science Journal were a spectacular success. Not only did the team classify a list of key compounds observed in the outgassing of Comet Wirtanen, they also discovered a high alcohol ratio for the comet along with an abnormal warming mechanism.

“46P / Wirtanen has one of the highest alcohol-aldehyde ratios measured to date of all comets,” says Neil Dello Russo (JHU / APL) in a current press release. “This gives us information about how carbon, oxygen and hydrogen molecules were distributed in the early solar system in which Wirtanen originated.”

Findings from the most recent NIRSPEC upgrade. Keck Observatory Astronomy Talk Video

The Keck study also found continuous warming of cometary material that sublimes through coma, the well-known ring of gas and dust that surrounds a comet’s core. The amount of heat is believed to decrease with distance and was more than what could be explained by simple incident solar radiation.

“Interestingly, we found that the temperature measured for water gas in the coma did not decrease significantly with distance from the nucleus, which suggests a warming mechanism,” says Erika Gibb (University of Missouri-St. Louis) in the current press release.

One possibility is ionization by sunlight close to the core. “Another possibility is that solid chunks of ice fly away from Wirtanen.” Says Gibb. This has been documented in the past. Especially during NASA’s EPOXI mission to Comet Hartley 2. “These chunks of ice fall away from the core and sublimate and release energy further out in the coma.”

This copious release of water is consistent with a young, hyperactive comet like 46P / Wirtanen. Like many periodic comets, Wirtanen was likely trapped in the inner solar system over the past million years. Ancient comets are considered to be one of the possible sources of the earth’s primordial seas.

An Arecibo radar image of Comet 46P captured during the 2018 pass near Earth. Photo credit: Arecibo / NASA / NSF

So far it has been difficult to capture the effects in the internal coma, where icy grains release water, in contrast to the sublimation of ethane, hydrogen cyanide and acetylene in the external coma; Missions like ESA’s Rosetta to Comet 67P / Churyumov-Gerasimenko only gave us a glimpse into this process, and the Earth’s atmosphere makes this process difficult to study.

The Keck Observatory Complex. Photo credit: WM Keck Observatory

The Keck team used the infrared NIRSPEC instrument to determine specific wavelengths of water transition, which made it possible to analyze the distribution of volatiles throughout the coma. This capability is a major innovation for a ground-based telescope.

Comet Wirtanen is also worth studying, as it has been shortlisted for exploration proposals in the past: NASA’s Comet Hopper mission would have sent a nuclear powered lander to the comet, and Wirtanen was the original destination of the Rosetta mission.

One day we can see Comet Wirtanen up close. For now, raise a glass to Wirtanen and NIRSPEC and keep in mind that comets could well be the source of the ice in this next refreshing drink.

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Guest contribution by Eric Worrall

According to the big computer, we are doomed to suffer more and more harmful weather extremes. But the researchers can’t tell us exactly why because their black box neural network won’t explain its prediction.

Human activity influences global precipitation, study results

Anthropogenic global warming has contributed to extreme precipitation events around the world, researchers say globally

Charlotte Burton
Wed July 7, 2021 3 p.m. AEST

…

Although there are regional variations and some locations are becoming drier, Met Office data shows that overall, heavy rainfall is increasing worldwide, meaning the rainiest days of the year are getting wetter. Changes in precipitation extremes – the number of days with very heavy rainfall – are also a problem. These short, intense periods of rain can lead to flash floods with devastating effects on infrastructure and the environment.

“We are already observing a temperature increase of 1.2 degrees Celsius compared to the pre-industrial level,” emphasized Dr. Sihan Li, a senior research fellow at Oxford University who was not involved in the study. She said: “If the warming continues to increase, we will have more intense episodes of extreme precipitation, but also extreme drought events.”

Li said that the machine learning method used in the study is state-of-the-art, but does not currently allow the assignment of individual factors that can influence precipitation extremes, such as anthropogenic aerosols, land use changes or volcanic eruptions.

The machine learning method used in the study learned from data alone. Madakumbura pointed out that in the future we can support this learning by dictating climate physics to the algorithm so that it learns not only whether the extreme rainfall has changed, but also the mechanisms why they have changed. “That’s the next step,” he said.

…

Read more: https://www.theguardian.com/environment/2021/jul/07/human-activity-influencing-global-rainfall-study-finds

The abstract of the study;

Anthropogenic influence on extreme precipitation over global land areas, which can be seen in several observation datasets

Gavin D. Madakumbura, Chad W. Thackeray, Jesse Norris, Naomi Goldenson & Alex Hall

The intensification of extreme precipitation under anthropogenic influences is predicted robustly by global climate models, but is very difficult to recognize in the observation data. Large internal variability distorts this anthropogenic signal. Models generate different orders of magnitude of precipitation reactions to anthropogenic forcing, mainly due to different schemes for the parameterization of processes on a subgrid scale. In the meantime, there are several global observation data sets of daily precipitation, which were developed with different techniques and inhomogeneously sampled data in space and time. Previous attempts to identify the human impact on extreme precipitation did not take into account the model uncertainty and were limited to certain regions and observation datasets. With machine learning methods that take these uncertainties into account and identify the temporal development of the spatial pattern, we find a physically interpretable anthropogenic signal that can be detected in all global observation data sets. Machine learning efficiently generates multiple lines of evidence that support the detection of an anthropogenic signal in extreme global precipitation.

Read more: https://www.nature.com/articles/s41467-021-24262-x

As an IT professional who has developed commercial AI systems, I find it incredible that the researchers appear naive enough to believe that their AI machine spending has value without corroborating the evidence. They admit they will try to understand how their AI works – but in my opinion they skipped the gun and made big claims based on a black box result.

Consider the following;

Amazon has ditched the AI ​​recruiting tool that prefers men for technical jobs

Specialists have been creating computer programs for reviewing résumés since 2014 in order to automate the search process

…

Amazon’s machine learning specialists discovered a big problem: their new recruiting engine didn’t like women.

…

But in 2015, the company found that its new system was not evaluating candidates for software developer jobs and other technical positions on a gender-neutral basis.

This is because Amazon’s computer models were trained to screen applicants by observing samples in résumés submitted to the company over a 10 year period. Most came from men, reflecting male dominance in the tech industry.

In fact, Amazon’s system taught itself that male candidates are preferred. It punished CVs containing the word “women”, as in “Women’s Chess Club Captain”. And it has downgraded graduates from two all-women colleges, according to people familiar with the matter.

Amazon has edited the programs in such a way that they are neutral to these special conditions. But that wasn’t a guarantee that the machines wouldn’t develop other ways of sorting candidates that could prove discriminatory, people said.

…

Read more: https://www.theguardian.com/technology/2018/oct/10/amazon-hiring-ai-gender-bias-recruiting-engine

In retrospect, it is clear what happened. The Amazon AI was told to try to select the most suitable candidates and it found that more male candidates were being accepted for technical jobs, likely because more male candidates were applying. It was concluded from this that men are more suitable for technical professions.

It is important to note that this male bias in engineering professions is a purely Western cultural problem. When I went to a software development shop in Taipei, there were as many women as men developing software. The women I met in western IT shops and in this IT shop in Taipei were just as smart and tech-savvy as any man. Somehow we persuade our women not to take up technical professions.

My point is, when scientists unleash a black box AI on a dataset, they have no way of knowing if that AI’s output is what they think it is until they carefully tear the AI ​​apart to find out exactly how it formed his conclusions.

Climatologists believe they have discovered a significant camouflaged anthropogenic impact. Or they may have discovered a large hidden bias in their data or models. To be fair, they admit that there could be problems with their training data and the climate models they use to retrospectively see what conditions would have been without anthropogenic impact. “… Additionally, the training GCMs may underestimate the low frequency natural variability such as the Atlantic multidecadal variability and the Pacific decadal oscillation. …“. That admission should have been her headline.

By the time they break down their black box system, figure out exactly how their AI is finishing up, and present the actual method for review, the method currently hidden in their AI, it seems remarkably premature to make a big announcement, just because they like the look of their result.

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