Among the more confounding planets discovered to date are “hot Jupiters” — massive balls of gas that are about the size of our own Jovian planet but that zing around their stars in less than 10 days, in contrast to Jupiter’s plodding, 12-year orbit. Scientists have discovered about 400 hot Jupiters to date. But exactly how these weighty whirlers came to be remains one of the biggest unsolved mysteries in planetary science.

Now, astronomers have discovered one of the most extreme ultrahot Jupiters — a gas giant that is about five times Jupiter’s mass and blitzes around its star in just 16 hours. The planet’s orbit is the shortest of any known gas giant to date.

Due to its extremely tight orbit and proximity to its star, the planet’s day side is estimated to be at around 3,500 Kelvin, or close to 6,000 degrees Fahrenheit — about as hot as a small star. This makes the planet, designated TOI-2109b, the second hottest detected so far.

Judging from its properties, astronomers believe that TOI-2109b is in the process of “orbital decay,” or spiraling into its star, like bathwater circling the drain. Its extremely short orbit is predicted to cause the planet to spiral toward its star faster than other hot Jupiters.

The discovery, which was made initially by NASA’s Transiting Exoplanet Survey Satellite (TESS), an MIT-led mission, presents a unique opportunity for astronomers to study how planets behave as they are drawn in and swallowed by their star.

“In one or two years, if we are lucky, we may be able to detect how the planet moves closer to its star,” says Ian Wong, lead author of the discovery, who was a postdoc at MIT during the study and has since moved to NASA Goddard Space Flight Center. “In our lifetime we will not see the planet fall into its star. But give it another 10 million years, and this planet might not be there.”

The discovery is reported today in the Astronomical Journal and is the result of the work of a large collaboration that included members of MIT’s TESS science team and researchers from around the world.

Transit track

On May 13, 2020, NASA’s TESS satellite began observing TOI-2109, a star located in the southern portion of the Hercules constellation, about 855 light years from Earth. The star was identified by the mission as the 2,109th “TESS Object of Interest,” for the possibility that it might host an orbiting planet.

Over nearly a month, the spacecraft collected measurements of the star’s light, which the TESS science team then analyzed for transits — periodic dips in starlight that might indicate a planet passing in front of and briefly blocking a small fraction of the star’s light. The data from TESS confirmed that the star indeed hosts an object that transits about every 16 hours.

The team notified the wider astronomy community, and shortly after, multiple ground-based telescopes followed up over the next year to observe the star more closely over a range of frequency bands. These observations, combined with TESS’ initial detection, confirmed the transiting object as an orbiting planet, which was designated TOI-2109b.

“Everything was consistent with it being a planet, and we realized we had something very interesting and relatively rare,” says study co-author Avi Shporer, a research scientist at MIT’s Kavli Institute for Astrophysics and Space Research.

Day and night

By analyzing measurements over various optical and infrared wavelengths, the team determined that TOI-2109b is about five times as massive as Jupiter, about 35 percent larger, and extremely close to its star, at a distance of about 1.5 million miles out. Mercury, by comparison, is around 36 million miles from the Sun.

The planet’s star is roughly 50 percent larger in size and mass compared to our Sun. From the observed properties of the system, the researchers estimated that TOI-2109b is spiraling into its star at a rate of 10 to 750 milliseconds per year — faster than any hot Jupiter yet observed.

Given the planet’s dimensions and proximity to its star, the researchers determined TOI-2109b to be an ultrahot Jupiter, with the shortest orbit of any known gas giant. Like most hot Jupiters, the planet appears to be tidally locked, with a perpetual day and night side, similar to the Moon with respect to the Earth. From the month-long TESS observations, the team was able to witness the planet’s varying brightness as it revolves about its axis. By observing the planet pass behind its star (known as a secondary eclipse) at both optical and infrared wavelengths, the researchers estimated that the day side reaches temperatures of more than 3,500 Kelvin.

“Meanwhile, the planet’s night side brightness is below the sensitivity of the TESS data, which raises questions about what is really happening there,” Shporer says. “Is the temperature there very cold, or does the planet somehow take heat on the day side and transfer it to the night side? We’re at the beginning of trying to answer this question for these ultrahot Jupiters.”

The researchers hope to observe TOI-2109b with more powerful tools in the near future, including the Hubble Space Telescope and the soon-to-launch James Webb Space Telescope. More detailed observations could illuminate the conditions hot Jupiters undergo as they fall into their star.

“Ultrahot Jupiters such as TOI-2109b constitute the most extreme subclass of exoplanet,” Wong says. “We have only just started to understand some of the unique physical and chemical processes that occur in their atmospheres — processes that have no analogs in our own solar system.”

Future observations of TOI-2109b may also reveal clues to how such dizzying systems come to be in the first place. “From the beginning of exoplanetary science, hot Jupiters have been seen as oddballs,” Shporer says. “How does a planet as massive and large as Jupiter reach an orbit that is only a few days long? We don’t have anything like this in our solar system, and we see this as an opportunity to study them and help explain their existence.”

This research was supported, in part, by NASA.

“This is the first study to report that among individuals with a least one risk factor for heart failure, those taking aspirin were more likely to subsequently develop the condition than those not using the medication,” said study author Dr. Blerim Mujaj of the University of Freiburg, Germany. “While the findings require confirmation, they do indicate that the potential link between aspirin and heart failure needs to be clarified.”

The influence of aspirin on heart failure is controversial. This study aimed to evaluate its relationship with heart failure incidence in people with and without heart disease and assess whether using the drug is related to a new heart failure diagnosis in those at risk.

The analysis included 30,827 individuals at risk for developing heart failure who were enrolled from Western Europe and the US into the HOMAGE study. “At risk” was defined as one or more of the following: smoking, obesity, high blood pressure, high cholesterol, diabetes and cardiovascular disease. Participants were aged 40 years and above and free of heart failure at baseline. Aspirin use was recorded at enrolment and participants were classified as users or non-users. Participants were followed-up for the first incidence of fatal or non-fatal heart failure requiring hospitalisation.

The average age of participants was 67 years and 34% were women. At baseline, a total of 7,698 participants (25%) were taking aspirin. During the 5.3-year follow-up, 1,330 participants developed heart failure.

The investigators assessed the association between aspirin use and incident heart failure after adjusting for sex, age, body mass index, smoking, alcohol use, blood pressure, heart rate, blood cholesterol, creatinine, hypertension, diabetes, cardiovascular disease, and treatment with renin-angiotensin-aldosterone-system inhibitors, calcium channel blockers, diuretics, beta-blockers and lipid-lowering drugs. Taking aspirin was independently associated with a 26% raised risk of a new heart failure diagnosis.

To check the consistency of the results, the researchers repeated the analysis after matching aspirin users and non-users for heart failure risk factors. In this matched analysis, aspirin was associated with a 26% raised risk of a new heart failure diagnosis. To check the results further, the analysis was repeated after excluding patients with a history of cardiovascular disease. In 22,690 participants (74%) free of cardiovascular disease, aspirin use was associated with a 27% increased risk of incident heart failure.

Dr. Mujaj said: “This was the first large study to investigate the relationship between aspirin use and incident heart failure in individuals with and without heart disease and at least one risk factor. Aspirin is commonly used — in our study one in four participants were taking the medication. In this population, aspirin use was associated with incident heart failure, independent of other risk factors.”

He concluded: “Large multinational randomised trials in adults at risk for heart failure are needed to verify these results. Until then, our observations suggest that aspirin should be prescribed with caution in those with heart failure or with risk factors for the condition.”

Story Source:

Materials provided by European Society of Cardiology. Note: Content may be edited for style and length.

As part of the Australian Imaging, Biomarkers and Lifestyle Study of ageing, researchers from Edith Cowan University (ECU) investigated whether coffee intake affected the rate of cognitive decline of more than 200 Australians over a decade.

Lead investigator Dr Samantha Gardener said results showed an association between coffee and several important markers related to Alzheimer’s disease.

“We found participants with no memory impairments and with higher coffee consumption at the start of the study had lower risk of transitioning to mild cognitive impairment — which often precedes Alzheimer’s disease — or developing Alzheimer’s disease over the course of the study,” she said.

Drinking more coffee gave positive results in relation to certain domains of cognitive function, specifically executive function which includes planning, self-control, and attention.

Higher coffee intake also seemed to be linked to slowing the accumulation of the amyloid protein in the brain, a key factor in the development of Alzheimer’s disease.

Dr Gardener said although further research was needed, the study was encouraging as it indicated drinking coffee could be an easy way to help delay the onset of Alzheimer’s disease.

“It’s a simple thing that people can change,” she said.

“It could be particularly useful for people who are at risk of cognitive decline but haven’t developed any symptoms.

“We might be able to develop some clear guidelines people can follow in middle age and hopefully it could then have a lasting effect.”

Make it a double

If you only allow yourself one cup of coffee a day, the study indicates you might be better off treating yourself to an extra cup, although a maximum number of cups per day that provided a beneficial effect was not able to be established from the current study.

“If the average cup of coffee made at home is 240g, increasing to two cups a day could potentially lower cognitive decline by eight per cent after 18 months,” Dr Gardener said.

“It could also see a five per cent decrease in amyloid accumulation in the brain over the same time period.”

In Alzheimer’s disease, the amyloid clumps together forming plaques which are toxic to the brain.

The study was unable to differentiate between caffeinated and de-caffeinated coffee, nor the benefits or consequences of how it was prepared (brewing method, the presence of milk and/or sugar etc).

Dr Gardener said the relationship between coffee and brain function was worth pursuing.

“We need to evaluate whether coffee intake could one day be recommended as a lifestyle factor aimed at delaying the onset of Alzheimer’s disease,” she said.

More than just caffeine

Researchers are yet to determine precisely which constituents of coffee are behind its seemingly positive effects on brain health.

Though caffeine has been linked to the results, preliminary research shows it may not be the sole contributor to potentially delaying Alzheimer’s disease.

“Crude caffeine” is the by-product of de-caffeinating coffee and has been shown to be as effective in partially preventing memory impairment in mice, while other coffee components such as cafestol, kahweol and Eicosanoyl-5-hydroxytryptamide have also been seen to affect cognitive impairment in animals in various studies.

‘Higher Coffee Consumption Is Associated With Slower Cognitive Decline and Less Cerebral A?-Amyloid Accumulation Over 126 Months: Data From the Australian Imaging, Biomarkers, and Lifestyle Study’ was published in Frontiers of Ageing Neuroscience.

The findings shed new light on the history of our ancestors and debunk old assumptions that infant mortality rates were consistently high in ancient populations.

The study also opens up the possibility mothers from early human societies may have been much more capable of caring for their children than previously thought.

“It has long been assumed that if there are a lot of deceased babies in a burial sample, then infant mortality must have been high,” lead author Dr Clare McFadden, from the ANU School of Archaeology and Anthropology, said.

“Many have assumed that infant mortality was very high in the past in the absence of modern healthcare.

“When we look at these burial samples, it actually tells us more about the number of babies that were born and tells us very little about the number of babies that were dying, which is counterintuitive to past perceptions.”

The researchers examined United Nations (UN) data from the past decade for 97 countries that looked at infant mortality, fertility and the number of deaths that occurred during infancy. The analysis revealed that fertility had a much greater influence on the proportion of deceased infants than the infant mortality rate.

Because there is very little known about early human societies, the UN data helped the researchers make interpretations about humans from the past 10,000 years.

“Archaeology has often looked at the proportion of deceased infants to learn something about infant mortality. There was an assumption that nearly half, 40 per cent, of all babies born in prehistoric populations died within the first year of their lives,” Dr McFadden said.

After analysing the UN data, Dr McFadden found no evidence to support this assumption.

“Burial samples show no proof that a lot of babies were dying, but they do tell us a lot of babies were being born,” she said.

“If mothers during that time were having a lot of babies, then it seems reasonable to suggest they were capable of caring for their young children.”

The ANU findings could help researchers understand more about humans that inhabited the Earth tens of thousands of years ago and in particular, how mothers in ancient societies cared for and interacted with their children.

Dr McFadden said as we piece together more clues about the history of humans, it’s important we “bring some humanity” back to our ancestors.

“Artistic representations and popular culture tend to view our ancestors as these archaic and incapable people, and we forget their emotional experience and responses such as the desire to provide care and feelings of grief date back tens of thousands of years, so adding this emotional and empathetic aspect to the human narrative is really important,” she said.

The researchers would also like to see greater emphasis placed on the stories of women in past populations, which they say have long been neglected in favour of male stories.

“We hear a lot of stories about conflict involving males and even narratives around colonisation and expansion of populations tend to have a focus on men and I think it’s really important to be telling these stories of women in the past and what the female experience was like, including the roles they played in the community and as a mother,” Dr McFadden said.

“We hope that further research, applied with the lens of our findings, will add to our understanding of infant care and motherhood in the past.”

Gender perception is much more complicated in children because gender differences in speech may emerge before sex-related anatomical differences between speakers. This suggests listeners may need to consider speaker age when guessing speaker gender and the perception of gender may depend on acoustic information not strictly related to anatomical differences between boys and girls.

In the Journal of the Acoustical Society of America, published by the Acoustical Society of America through AIP Publishing, researchers at the University of California, Davis and the University of Texas at Dallas report developing a database of speech samples from children ages 5 to 18 to explore two questions: What types of changes occur in children’s voices as they become adults, and how do listeners adjust to the enormous variability in acoustic patterns across speakers?

Listeners assess a speaker’s gender, age, height, and other physical characteristics based primarily on the speaker’s voice pitch and on the resonance (formant frequencies) of their voice.

“Resonance is related to speaker height — think violin versus cello — and is a reliable indicator of overall body size,” said Santiago Barreda, from the University of California, Davis. “Apart from these basic cues, there are other more subtle cues related to behavior and the way a person ‘chooses’ to speak, rather than strictly depending on the speaker’s anatomy.”

When Barreda and Peter Assmann, from the University of Texas at Dallas, presented listeners with both syllables and sentences from different speakers, gender identification improved for sentences. They said this supports the stylistic elements of speech that highlight gender differences and come across better in sentences.

They made two other important findings. First, listeners can reliably identify the gender of individual children as young as 5.

“This is well before there are any anatomical differences between speakers and before there are any reliable differences in pitch or resonance,” said Barreda. “Based on this, we conclude that when the gender of individual children can be readily identified, it is because of differences in their behavior, in their manner of speaking, rather than because of their anatomy.”

Second, they found identification of gender of speakers must take place jointly with the identification of age and likely physical size.

“Essentially, there is too much uncertainty in the speech signal to treat age, gender, and size as independent decisions,” he said. “One way to resolve this is to consider, for example, what do 11-year-old boys sound like, rather than what do males sound like and what do 11-year-olds sound like, as if these were independent questions.”

Their work suggests “perception of gender can depend on subtle cues based on behavior and not anatomy,” said Barreda. “In other words, gender information in speech can be largely based on performance rather than on physical differences between male and female speakers. If gendered speech followed necessarily from speaker anatomy, there would be no basis to reliably identify the gender of little girls and boys.”

The performative nature of gender has long been argued on theoretical grounds, and these experimental results support this perspective.