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Stars and planets are naturally associated with one another. While some planets have gone rogue and are drifting through space, the vast majority are in solar systems, where they’re gravitationally bound and orbit their stars in predictable ways. But some planets stray too close to their stars, with dire consequences. These exoplanets have something to teach us about the exoplanet population.

Our exoplanet discoveries (~6,000 and counting) have shown us that our Solar System is not representative. Other solar systems contain planets nothing like ours, in orbits not seen in our Solar System. TOI-1227b is one of them.

TOI-1227b is a roughly Jupiter-size planet with about 20% of Jupiter’s mass. It orbits an M-dwarf, or red dwarf star, about 330 light-years away. It was discovered in 2022 in data from NASA’s Transiting Exoplanet Survey Satellite (TESS).

TOI-1227b is suffering an existential crisis. It orbits extremely close to its star, only about 1/5th as far away as Mercury is from the Sun. New research shows that this planet is young, only about eight million years old. It’s a diaper-wearing infant when compared to Earth. Sadly for this young planet, instead of putting on weight, it’s losing its mass.

The research is titled “The Age and High Energy Environment of the Very Young Transiting Exoplanet TOI 1227b,” and will be published in The Astrophysical Journal but is available at arxiv.org. The lead author is Attila Varga, a Ph.D. student at the Rochester Institute of Technology (RIT) in New York. At only eight million years old, the exoplanet is the second youngest planet astronomers have ever found transiting in front of its star.

“We have conducted new X-ray imaging and optical spectroscopic observations of TOI 1227 aimed at ascertaining its age and the influence of its high-energy radiation on the exoplanet, TOI 1227b,” the researchers write.

The star it orbits, TOI-1227, is much smaller and dimmer than the Sun. As an M-dwarf, it’s far less massive than the Sun, and much dimmer in visible light. However, that dimness doesn’t describe the entire spectrum of the star’s output.

M-dwarfs are notorious for their extreme flaring, which produces powerful X-rays. Unlike the Sun, M-dwarfs are fully convective. Convection takes place throughout the interior of the star, which creates the powerful magnetic fields responsible for the flaring. In TOI-1227 b’s case, the unfortunate young gas giant is right in the crosshairs of this destructive flaring.

This illustration shows how low-mass, M-dwarf stars are fully convective. This convection creates the stars’ powerful, destructive flaring. Image Credit: NASA/CXC/M.Weiss

“It’s almost unfathomable to imagine what is happening to this planet,” said lead author Varga in a press release. “The planet’s atmosphere simply cannot withstand the high X-ray dose it’s receiving from its star.”

“Our modeling suggests that TOI 1227b is currently undergoing rapid atmospheric mass loss at rates on the order of ∼ 10^12 g s^−1,” the authors write. That equates to losing about 1 million metric tons of its atmosphere every single second. Varga and his co-authors calculated that in only one billion years, the planet will lose its entire atmosphere.

Powerful X-rays from stars like TOI 1227 strip away exoplanet atmospheres with several different, yet connected, mechanisms.

This figure shows TOI-1227’s spectral energy distribution. The red points are from archival photometry from GAIA, 2MASS, and WISE, and blue points are synthetic photometry points from an atmospheric model. The black line represents the best fit. Since X-rays span from about 0.01 to 10 nanometers, the figure shows that X-rays are blasting away at the exoplanet TOI-1227b. Image Credit: Varga et al. 2025. The Astrophysical Journal.

When X-rays strike molecules in the atmosphere, they ionize them and heat them up. This can heat the atmosphere to thousands of degrees Kelvin, which makes the atmosphere puff up. As the atmosphere extends further into space, the planet’s gravity has a weaker hold on it. The heating can be even more extreme in some cases, and this can essentially boil away some lighter molecules like molecular hydrogen.

Photodissociation plays a role, too. X-rays have enough energy to break water molecules apart into hydrogen and oxygen atoms. Since hydrogen is so light, it can easily escape to space. On top of that, the X-rays can raise the temperature of the star’s stellar wind, giving it more energy and making it more efficient at stripping away the atmosphere.

“A crucial part of understanding planets outside our solar system is to account for high-energy radiation like X-rays that they’re receiving,” said co-author Joel Kastner, also of RIT. “We think this planet is puffed up, or inflated, in large part as a result of the ongoing assault of X-rays from the star.”

The researchers think that the planet is losing the mass equivalent to two Earth atmospheres every two centuries. While many things astronomers discover take a long time to play out, this is happening much more quickly. Most things in astronomy are measured in millions or billions of years, not centuries.

“The future for this baby planet doesn’t look great,” said co-author Alexander Binks of the Eberhard Karls University of Tübingen in Germany. “From here, TOI 1227 b may shrink to about a tenth of its current size and will lose more than 10 percent of its weight.”

A hypothetical visualization of TOI-1227b. The planet is rapidly losing its atmosphere as intense X-ray radiation from its star strips it away. Image Credit: NASA Eyes on Exoplanets

Some of these numbers are not exact, because a lot depends on understanding the mass of the planet. In this case, that mass is proving elusive to determine exactly. To come up with these numbers, the team performed multiple simulations and settled on the most likely outcomes.

There’s a small planet radius gap in the exoplanet population, where planets with radii between 1.5 and 2 times Earth’s radius are very scarce. Photo-evaporation driven mass loss is the suspected cause of this gap, and astronomers want to observe planets like TOI 1227b to learn more about the process.

“The nearby, young transiting exoplanet system TOI 1227 represents a vital benchmark for understanding very early stages of exoplanet evolution around low-mass stars,” the researchers conclude, noting that “Follow-up photometric and spectroscopic observations aimed at further establishing the nature of the TOI 1227 system and providing tighter constraints on the mass and atmospheric mass loss,” are needed.

The hunt for potentially habitable rocky planets in our galaxy has been the holy grail of exoplanet studies for decades. While the discovery of over 5,900 exoplanets in over 4.400 planetary systems has been a remarkable achievement, only a small fraction (217) have been confirmed as terrestrial – aka. rocky or “Earth-like.” Furthermore, obtaining accurate information on a rocky exoplanet’s atmosphere is very difficult, since potentially habitable rocky planets are much smaller and tend to orbit closer to their stars.

Thanks to next-generation instruments like the James Webb Space Telescope (JWST), exoplanet studies are transitioning from discovery to characterization. However, no atmospheres have been clearly identified around rocky planets yet, and the atmospheric data Webb has collected so far is subject to some uncertainty. A summary of Webb’s findings was featured in a recent study by researchers from the Max Planck Institute for Astronomy (MPIA) and the Johns Hopkins University Applied Physics Laboratory (JHUAPL). Based on their summary, they recommend a “five-scale height challenge” to assist astronomers in atmospheric characterization.

The study was led by Laura Kreidberg, a Professor at the MPIA and the Director of its Atmospheric Physics of Exoplanets (APEx) Department. She was joined by Kevin B. Stevenson, a research astronomer at the JHUAPL, and the Consortium on Habitability and Atmospheres of M-dwarf Planets (CHAMPs). The preprint of the paper that details their findings, “A first look at rocky exoplanets with JWST,” recently appeared online and is being reviewed for publication in the Proceedings of the National Academy of Sciences (PNAS).

Artist’s impression of the surface of Barnard’s Star b. Credit: ESO/M. Kornmesser

As they outline in their paper, Webb has achieved some impressive milestones thanks to its advanced suite of sensitive and high-resolution infrared optics, combined with coronagraphs and spectrometers. “[T]he most precise transmission spectra for rocky planets yet, and detection of heat emanating from about half a dozen rocky planets,” Kreidberg told Universe Today via email. “JWST has also allowed us to push these measurements of thermal emission (heat) to cooler rocky planets than ever before – now as low as 100 degrees C (compared to 800 degrees C previously).”

Thanks to its observations, Webb has also enabled extensive theoretical work to predict the atmospheric properties of rocky planets. This is particularly true of those orbiting M-type red dwarf stars, which account for 80% of stars in the Milky Way. This has demonstrated that atmospheres can be shaped by many physical processes, including volatile elements delivered by comets and asteroids, atmospheric loss, interior-atmosphere interaction, and biological processes. Of these, atmospheric loss is especially important since it is unknown which rocky planets observed by Webb have retained their atmospheres.

Based on Webb’s observations to date, the concept of the “cosmic shoreline” has emerged as a popular framework to determine which planets are more likely to have atmospheres. According to this framework, planets with a higher escape velocity (more massive planets) and lower irradiation are more likely to retain atmospheres. However, it is still unknown how this “shoreline” is affected based on stellar type and irradiation history. Meanwhile, late-stage stars are known for exposing their planets to greater levels of high-level radiation, especially late M-type stars that are known to have extended UV-bright phases that can last up to 6 billion years.

Greater exposure to high-energy irradiation leads to greater atmospheric loss, and M-type stars are known for their intense flare activity. To address these unknowns, the team recommends a new framework to achieve greater precision in identifying rocky planet atmospheres. Said Kreidberger:

The five-scale height challenge is a goal to reach the measurement precision needed to detect Earth-like atmospheric features. The largest spectral feature in Earth’s atmosphere is carbon dioxide, and it spans about five scale heights (a unit astronomers use to refer to the typical vertical extent of an atmosphere). So far, the data is not precise enough to see a feature this small, so more observations are needed!

Artist’s impression of the surface of Proxima Centauri b. Credit: ESO/M. Kornmesser

Thanks to JWST’s large aperture, stability, and near-to-mid-infrared wavelength coverage, astronomers are now at a point where the characterization of atmospheres around rocky planets is finally possible. In particular, it is now possible to detect the tiny signals expected from volatile elements like water (H2O), carbon dioxide (CO2), methane (CH4), ammonia (NH3), carbon monoxide (CO), and others. Looking ahead, astronomers will be able to obtain transmission and emission spectra from rocky exoplanets around M-type stars during planetary transits and eclipses. Said Kreidberger:

The five-scale height challenge sets a benchmark for how precise the data needs to be to detect an Earth-like atmosphere. This is going to require both more data and better modelling to remove noise from the star and JWST’s detectors. There was already a JWST observing program (GO 7073, Charting the Cosmic Shoreline) approved to attempt this for a small sample of rocky planets most likely to have atmospheres.

While the JWST is incapable of studying the atmospheres of Earth analogs around Sun-like stars, future next-generation missions like the Habitable Worlds Observatory (HWO) will be able to do so via direct imaging. In the meantime, the framework proposed by Kreidberger’s team could help astronomers pave the way by constraining rocky exoplanet atmospheres further. “[W]e have made great progress with JWST already in our understanding of which rocky planets could have atmospheres,” added Kreidberger. “This is a critical first step, well before we get to biosignatures. We need to learn to walk before we can run!

Further Reading: arXiv

Wild tomatoes rooted on the raw lava of Fernandina and Isabela Islands have done something biologists once filed under “nearly impossible,” reviving a molecular defense that disappeared from their relatives millions of years ago during species evolution.

The phenomenon has been traced to a tiny tweak in the plants’ chemistry, and it now stands as the clearest plant example of reverse evolution, the re‑emergence of an ancestral trait after a long dormancy.

Lead author Adam Jozwiak at the University of California, Riverside, working with colleagues from the Weizmann Institute, mapped the unexpected comeback.

Evolution of wild tomatoes

Wild tomatoes on the islands produce a mix of bitter chemicals that help protect them from insects and animals that might try to eat them.

On the youngest islands, the mix has shifted toward an older type of toxin usually found in eggplants, not modern tomatoes, showing that this ancient version can still work better under harsh conditions like lava soil and intense heat.

The change comes down to a single enzyme in the plant that decides how its natural defense chemicals are made.

By slightly altering this enzyme, the plant switches back to an older version of its toxin that had been lost for millions of years.

“Just four amino acids changed everything,” reported the study team, noting that the modified enzyme brought back the older, more aggressive version of the toxin. It wasn’t a random mutation, but a precise shift that reactivated a long-dormant chemical pathway.

Life on lava and sand

The western Galápagos islands are among the youngest in the chain, with rugged volcanic ground and almost no soil. Plants growing there face intense heat, limited nutrients, and constant threats from insects and animals.

In those conditions, bringing back a stronger chemical defense gives the tomatoes a better chance of surviving, and evolution seems to have reached into the plant’s genetic history instead of creating something entirely new.

When tomato evolution hits reverse

Although it was once assumed that lost traits almost never return, research shows that evolution can sometimes retrace its steps. 

In some cases, structures that disappeared for millions of years have reappeared, such as larval stages in salamanders or wings in certain insects.

These reversals challenge the old idea that evolution always moves in one direction and suggest that dormant genetic pathways can be reactivated when conditions shift. 

The tomato work tightens the evidence because stereochemistry can be measured atom by atom, making accidental convergence unlikely.

Lessons for crop science

Changing four amino acids in GAME8 inside greenhouse tobacco forced the host to synthesize the ancestral toxin, showing that minimal editing is enough to remodel an entire metabolic branch.

Researchers now wonder whether carefully steering stereochemistry could dial pest resistance up or down in other crops while avoiding off‑flavors that plague tomato breeders. 

Island survey data hint at an evolutionary gradient: tomatoes on older eastern islands keep the modern toxin, central islands sit in the middle, and the youngest lava fields host plants in nearly full chemical retreat.

That pattern suggests evolution’s arrow is flexible, and under shifting climates crops might again reach backward for solutions thought obsolete.

How four amino acids changed the story

Most enzymes are highly specific, and even minor alterations can break them. But in this case, the GAME8 enzyme was surprisingly flexible.

By replacing just four amino acids in its active site, scientists restored the enzyme’s older behavior, allowing the plant to make the ancient version of its chemical defense again. 

This kind of precise control over a plant’s internal chemistry is unusual and suggests that nature sometimes keeps old instructions ready to use when needed. 

The researchers used molecular docking and structural models to predict which amino acids made the difference.

Lab tests confirmed their predictions, highlighting how small tweaks in sequence can flip a tomato plant’s entire chemical output.

This work also demonstrates how directed enzyme evolution, a common tool in biotechnology, occurs naturally under harsh selection pressures like those on the Galápagos lava fields.

Impacts beyond tomatoes

Tomatoes belong to the Solanaceae family, which includes peppers, potatoes, and tobacco. All of them produce related alkaloids, and this study suggests they might also hold buried chemical routes.

Understanding how GAME8 evolved can help scientists modify alkaloid profiles in related plants, potentially unlocking medicinal or agricultural uses with more precision.

Some glycoalkaloids are mildly toxic to humans, and breeders often try to reduce them. But with the ability to dial in the stereochemistry, it might be possible to keep the benefits while avoiding the downsides.

This also raises fresh questions for evolutionary theory, particularly around how often so-called “lost” traits are truly gone, or just waiting for the right trigger to come back.

The study is published in Nature Communications.

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Using cannabis could make changes to your body’s epigenetic code, research has discovered. The findings, which were published in a study in 2023, suggest that using marijuana in any way can affect the code that your body uses to switch on and off different genes. This research is vital to fully understanding the effects marijuana use has on the body and could open the door to further research down the line.

As one of the most used drugs in the world, the way that marijuana affects the human body is still not fully understood. We have some understanding of its impact, but this research shows that it has a much longer reach than scientists might have previously expected. One of the markers found during the research ties directly to the markers seen in tobacco use, suggesting a much closer association between the use of tobacco and marijuana.

Further, the researchers wanted to see how using cannabis changes the epigenetic code, as fully understanding this could help them ascertain whether it has any directly negative or positive effects on human health. Most notably, they wanted to see how it might affect the genes associated with aging, which are typically controlled by the body’s epigenetic code. Understanding changes to the body’s epigenetic code can help us understand how heat affects aging, as well as what the body’s epigenetic age is.

To conduct their research, the scientists used data gathered from willing participants that had their use of cannabis surveyed over the years. The researchers looked at blood samples taken five years apart, and compared the blood based on factors like consecutive cannabis use, as well as whether or not they had used the drug recently.

Together, the data showcased just how much using cannabis changes the epigenetic code. They found several markers that could be tied to both consecutive and recent use. However, the researchers note that additional research is needed to truly understand the connections and how far they reach throughout the code. For now, though, this research has at least provided some novel insights into the association between using marijuana and epigenetic factors.