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Science

Astronomers Find a Planet Like Jupiter, but It Doesn’t Have any Clouds

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Can you picture Jupiter without any observable clouds or haze? It isn’t easy since Jupiter’s latitudinal cloud bands and its Great Red Spot are iconic visual features in our Solar System. Those features are caused by upswelling and descending gas, mostly ammonia. After Saturn’s rings, Jupiter’s cloud forms are probably the most recognizable feature in the Solar System.

Now astronomers with the Center for Astrophysics | Harvard & Smithsonian (CfA) have found a planet similar in mass to Jupiter, but with a cloud-free atmosphere.

These planets are scarce, and astronomers think only about 7% of exoplanets are like this. The discovery allows scientists to study how they form. Without clouds in the way, a clearer view awaits.

The team of astronomers behind the finding published their results in The Astrophysical Journal Letters. The title is “Evidence of a Clear Atmosphere for WASP-62b: The Only Known Transiting Gas Giant in the JWST Continuous Viewing Zone.” Lead author of the study is Munazza Alam, a grad student at the CfA.

WASP-62b is the nearest planet to WASP-62, a main-sequence star almost 600 light-years from Earth. 62b is the only planet in the system. It’s just over half as massive as Jupiter, and orbits WASP-62 in about 4.5 days. It’s about 1.4 times as large as Jupiter. It falls squarely into the category of Hot Jupiters, with an average temperature of about 1330 K (1057 C; 1934 F.)

Can you picture Jupiter without clouds? We can’t either. Image Credit: Hubble/NASA/ESA

The planet’s temperature, size, and density properties aren’t rare. What’s rare is the cloudlessness of its atmosphere. And the exoplanet’s atmosphere is of special interest to lead author Alam. In a press release, Alam said, “For my thesis, I have been working on exoplanet characterization. I take discovered planets, and I follow up on them to characterize their atmospheres.”

The WASP name comes from the Wide Angle Search for Planets (WASP) South. The planet was first discovered in 2012 and was one of seven Hot Jupiters found at the same time.

WASP-62b was discovered with WASP, but Alam and her colleagues used the Hubble to study it more closely. “I’ll admit that at first, I wasn’t too excited about this planet,” Alam said. “But once I started to take a look at the data, I got excited.”

Using spectroscopy, they watched closely as the planet transited in front of its star three times, looking for potassium and sodium. As the starlight passed through the planet’s atmosphere they identified sodium’s complete spectroscopic signature, but no potassium. The sodium signature told them that the atmosphere was clear.

“This is smoking gun evidence that we are seeing a clear atmosphere,” Alam said.

A screenshot of WASP-62b from NASA’s Eyes on Exoplanets website. Image Credit: NASA

In an email exchange with Universe Today, Alam elaborated on the team’s spectroscopic findings and what they mean.

The focus on potassium and sodium is based on a couple of things. First of all, their spectra are easily observable in optical light. “Sodium and potassium are two species that are readily observable in exoplanet atmosphere observations taken at optical wavelengths, and their presence or absence can help us infer if there are clouds or hazes in an exoplanet’s atmosphere,” Alam said.

Sodium and potassium also play a role in exoplanet atmospheres, though the details aren’t clear. “Sodium and potassium are two elements that play an interesting – yet not well understood – role in the atmospheric physics and chemistry of exoplanets,” Alam explained. She also mentioned that sodium was the first absorption feature identified in an exoplanet’s atmosphere.

The detection of sodium’s complete spectroscopic signature tells astronomers that the atmosphere is clear, even if there’s no way to see the atmosphere. “Clouds in a planet’s atmosphere will mask or obscure parts of the absorption line,” Alam explained. “In the absence of clouds, we can resolve the full sodium signature – which has a tent-like shape with a peak at the core of the absorption feature and broad line wings. For our observations of WASP-62b, this is the second time that we’ve observed the full sodium feature (i.e., with its line wings) in an exoplanet and the first time that we’ve done so from space.”

This figure from the study shows the Hubble Space Telescope Imaging Spectrograph data for WASP-62b and the only other known exoplanet with a clear atmosphere, WASP-96b. Both exoplanets show the “…prominent pressure-broadened wings of the Na D-lines at 0.59 ?m.” Seeing the sodium spectrum with wings indicates that both planets have clear atmospheres. WASP-96b also shows the presence of lithium and potassium. Image Credit: Alam et al, 2021.

But the complete sodium signature does more than tell us that the exoplanet’s atmosphere is cloud-free. It can help explain how much sodium there is and indicate what other elements are in the atmosphere.

“Not only does it tell us that the atmosphere is clear, it can also help us to constrain really precise abundances (quantities) of sodium – as well as other elements that are present in the planet’s atmosphere,” Alam said. “These abundances are useful for measuring key quantities that can help us trace back the origins and evolution of this planet.”

There’s clearly something different going on when a cloud-free planet forms. Since there are so few of them, astronomers are only at the beginning of studying them. The only other cloud-free exoplanet that we know of is the hot Saturn named WASP-96b, found in 2018.

It’ll be up to the James Webb Space Telescope to examine this exoplanet’s atmosphere more closely. And its clear skies make that prospect even more exciting. The Webb’s advanced observing capabilities mean it should be able to identify even more of the chemical constituents in WASP-62b’s atmosphere.

“In preparation for JWST, identifying targets that are cloud-free/haze-free is important for mobilizing community efforts to observe the best planets for detailed atmospheric follow-up.”

From “Evidence of a Clear Atmosphere for WASP-62b: The Only Known Transiting Gas Giant in the JWST Continuous Viewing Zone.”

Due to JWST’s orientation and position in space, it’ll have two small continuous viewing zones (CVZ). They’re centred on each pole of the ecliptic. Fortune is smiling on Alam and other exoplanet scientists because WASP-62b is in one of Webb’s CVZs.

James Webb’s field of view contains two continuous viewing zones, indicated by ovals in the image. The rest of the JWST’s field of regard sweeps through the sky over time. As luck would have it, WASP-62b is in one of JWST’s CVZs. Image Credit: NASA/JWST.

The team of researchers even predicted what the JWST might find in 62b’s atmosphere. In their paper they write “We predict that JWST observations of WASP-62b, within the scope of the ERS program, can conclusively detect Na (12.1?), H2O (35.6?), FeH (22.5?), SiH (6.3?), NH3 (11.1?), CO (8.1?), CO2 (9.7?), and CH4 (3.6?).” They also say that the JWST can offer precise constraints on the abundance of chemicals in the atmosphere.

As part of their work, and to help make the case for follow-up observations with the Webb, the team predicted what the Webb might find. Image Credit: Alam et al, 2021.

In their conclusion, the authors make their case for follow-up observations of WASP-62b with the JWST.

“In preparation for JWST, identifying targets that are cloud-free/haze-free is important for mobilizing community efforts to observe the best planets for detailed atmospheric follow-up. Although alternative targets have since been put forward, WASP-62 is the only star in the JWST CVZ with a known transiting giant planet that is bright enough for high-quality atmospheric characterization via transit spectroscopy.”

The James Webb Space Telescope is scheduled to launch at the end of October 2021.

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Health

New Covid variant and children: CDC doesn’t know if variants cause rare complication in kids

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Multisystem inflammatory syndrome (MIS-C) in children is a troubling complication of Covid-19 infection that can cause heart damage and typically shows up about three weeks after a child has been infected. Many MIS-C cases follow a Covid-19 infection that had no symptoms.

While children are much less likely than adults to be hospitalized or die from Covid-19, children are as just as likely as adults to become infected.

About 2.68 million children in the US have tested positive for the virus as of January 21, according to the American Academy of Pediatrics, and the number of infections has increased recently. Last week alone, 165,480 new child cases were identified through testing, the report said. That’s an 16% increase in child Covid-19 cases over two weeks. Children represent 12.7% of all cases in the US.

The CDC says that as of the end of December, it had reports of 1,659 cases of MIS-C.

If the Covid-19 variants are more contagious, then there is a chance that there could be more instances of MIS-C, but the CDC said it does not have the evidence yet to determine if the variants are leading to more cases.

“All I can say right now is we don’t know,” Dr. Angela Campbell, a CDC medical officer with the Influenza Division, told a meeting of the CDC’s Advisory Committee on Immunization Practices.

“We are very interested in that question,” Campbell said.

The CDC is “certainly concerned” about the variants and is encouraging public health departments to be on the look out for cases, Campbell added. She said the CDC has heard from a handful of states that have said they are seeing more MIS-C cases, but it’s unclear if that is due to the overall surge in Covid-19 cases or if it is related to the variant.

“It’s just not possible to figure that out right now,” Campbell said.

MIS-C has disproportionately affected children of color. There is a sixfold higher incidence of MIS-C among Black children relative to White children. Hispanic children are four times as likely to develop MIS-C and Asian Pacific Islander children are three times as likely to develop the condition as White children, Campbell said.

Children recover with prompt treatment. The CDC advises that parents or caregivers contact a doctor right away if kids have fever, abdominal pain, vomiting, diarrhea, neck pain, rash, bloodshot eyes or extra tiredness.

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Technology

“Seamless updates” is a great Android feature that the Samsung Galaxy S21 Ultra still doesn’t have

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‘Seamless updates’, first introduced back in 2016 and arrived on every Google Pixel phone, allows for firmware updates to be installed to a secondary partition while the phone remains in use. This eliminates downtime between firmware updates to a single reboot, after which the secondary partition becomes the main one and the update has already completed. This also acts as a failsafe in case an update goes wrong – the system can fall back on the previous partition.

Update notification on a Samsung Galaxy S21 Ultra

Google has backed off on this requirement since it’s no longer in the Android CDD (Compatibility Definition Document). The CDD acts as a guideline for Android OEMs and lists what Google requires from OEMs for their devices to be compatible with the newest version of Android.

It’s presumed that the requirement was backed off by pressure from OEMs like Samsung, who’s latest Galaxy S21 smartphones do not have the framework to support seamless updates. Android Police has confirmed that the new Samsung Galaxy S21 Ultra does not support the feature. While Google had previously planned to require the feature, it is now mentioned in the CDD that OEMs “SHOULD” support a/b system updates. The “a” and “b” refer to the identical partitions that alternate between firmware updates.

Without seamless updates, an Android device will need to spend several minutes of downtime on a bootloader screen, without the ability to use any applications or make any phone calls, even of the emergency kind. Samsung’s reasoning for delaying such a feature is unknown.

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Health

Being fit doesn’t outweigh the dangers of obesity, new study suggests

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New research has just plunged a dagger through the core of the mentality that you can be “fat but fit.”

Physical activity does nothing to cancel the harmful effects of excess body weight on cardiovascular health, according to a bombshell study published Thursday in the European Journal of Preventive Cardiology, a journal of the European Society of Cardiology.

The findings contradict previous studies concluding that maintaining physical activity could lessen the effects of extra body weight on heart health.

“One cannot be ‘fat but healthy,’ ” said the study’s author, Alejandro Lucia, a professor of exercise physiology at the European University of Madrid.
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“One cannot be ‘fat but healthy,’ ” said the study’s author, Alejandro Lucia, a professor of exercise physiology at the European University of Madrid. “This was the first nationwide analysis to show that being regularly active is not likely to eliminate the detrimental health effects of excess body fat. Our findings refute the notion that a physically active lifestyle can completely negate the deleterious effects of overweight and obesity.”

Lucia cites previous research that suggested, in adults and children, a “fat-but-fit” lifestyle could be in similar cardiovascular heath to those who are “thin but unfit” — and adds that’s led people astray from the true priority.

“This has led to controversial proposals for health policies to [prioritize] physical activity and fitness above weight loss,” he said. “Our study sought to clarify the links between activity, body weight, and heart health.”

SKIPPING DINNER MIGHT LEAD TO WEIGHT GAIN, NEW STUDY SAYS

This study surveyed data from 527,662 working Spanish adults, all insured by a large occupational risk prevention company. Thirty-two percent of the participants were women; The average age was 42.

They were categorized by activity level and body weight — with some 42 percent classified as normal weight with a body mass index (BMI) of 20 to 24.9. Approximately 41 percent were overweight, with a BMI of 25 to 29.9, while 18 percent were considered obese, with a BMI of 30 or above. The majority of the study’s pool, more than 63 percent, were physically inactive. About 24 percent were regularly active and just more than 12 percent were considered insufficiently active.

The research team then examined the associations between BMI, level of physical activity, and high cholesterol, high blood pressure and diabetes — the three of which carry big risks for heart attack and stroke.

They found that across all BMI measurements, any physical activity was linked to a lower likelihood of diabetes, high cholesterol and high blood pressure when compared to no exercise at all.

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“This tells us that everyone, irrespective of their body weight, should be physically active to safeguard their health,” said Lucia.

So yes, being active is important. But size still matters.

Regardless of activity levels, the overweight and obese participants faced higher cardiovascular risks than those with normal body weight. When compared to inactive normal-weight adults, physically active obese people were still about twice as likely to have high cholesterol, four times more likely to have diabetes and five times more likely to have high blood pressure.

“Exercise does not seem to compensate for the negative effects of excess weight,” he added. “This finding was also observed overall in both men and women when they were [analyzed] separately.”

Lucia concluded that obesity and inactivity must both be combatted.

“It should be a joint battle,” he said. “Weight loss should remain a primary target for health policies together with promoting active lifestyles.”

However, the study makes no mention or recommendations for diet — and when it comes to an example of physical activity, Lucia said “walking 30 minutes per day is better than walking 15 minutes a day.”

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Sean Heffron, MD, a cardiologist at the Center for the Prevention of Cardiovascular Diseases at NYU Langone Health, underscored that obesity is a risk factor for cardiovascular disease — as is insufficient physical activity — but weight loss requires a two-part formula.

“Exercise in and of itself isn’t the kind of way to lose weight,” he said. “It’s complementary to having an ideal body weight,” but improving your diet is the other piece of the puzzle.

This content originally appeared in The New York Post.

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