Irregular appearances of glacial and interglacial climate states

During the last 2.6 million years of Earth's climate has altered between glacial and interglacial states. As such, there have been times in which the transition between the two climate states appeared with either regular or irregular periodicity. AWI researcher Peter Kohler has now discovered that the irregular appearance of interglacials has been more frequent than previously thought. His study makes a significant contribution to our understanding of Earth's fundamental climate changes.

Credit: Pixabay

In order to understand human beings' role in the development of our current climate, we have to look back a long way, since there has always been climate change - albeit over vastly different timescales than the anthropogenic climate change, which is mainly due to the use of fossil fuels over the past 200 years. Without humans, for millions of years, climate altered between glacial and interglacial states over periods of many thousands of years, mainly because of the Earth's tilt which changes by a few degrees with a periodicity of 41,000 years. 

This in turn changes the angle at which the sun's rays strike Earth - and as such the energy that reaches the planet, especially at high latitudes in summer. However, there is strong evidence that during the course of the last 2.6 million years, interglacials have repeatedly been 'skipped'. The Northern Hemisphere - particularly North America - remained frozen for long periods, despite the angle of the axial tilt changing to such an extent that more solar energy once again reached Earth during the summer, which should have melted the inland ice masses. This means Earth's tilt can't be the sole reason for Earth's climate to alter between glacial and interglacial states.

In order to solve the puzzle, climate researchers are investigating more closely at what points in Earth's history irregularities occurred. Together with colleagues at Utrecht University, physicist Peter Kohler from the Alfred Wegener Institute (AWI) has now made a significant contribution towards providing a clearer picture of the sequence of glacial and interglacial periods over the last 2.6 million years. Until now, experts thought that, especially over the past 1.0 million years, glacial and interglacial periods deviated from their 41,000- year cycle, and that interglacial periods were skipped, as a result of which some glacial periods lasted for 80,0000 or even 120,000 years. "For the period between 2.6 and 1.0 million years ago, it was assumed that the rhythm was 41,000 years," says Peter Kohler. But as his study, which has now been published in the scientific journal Nature Communications, shows, there were also repeated irregularities during the period between 2.6 and 1.0 million years ago.

Kohler's study is particularly interesting because he re-evaluated a well-known dataset that researchers have been using for several years - the LR04 climate dataset - yet arrived at completely different conclusions. This dataset consists of a global evaluation of core samples from deep-sea sediments that are millions of years old, and includes measurements from the ancient shells of microscopic, single-celled marine organisms - foraminifera - that were deposited on the ocean floor. Foraminifera incorporate oxygen from the seawater into their calcium shells. But over millennia, the level of specific oxygen isotopes - oxygen atoms that have differing numbers of neutrons and therefore different masses - varies in seawater.

18O reveals what the world was like in the past

The LR04 dataset contains measurements of the ratio of the heavy oxygen isotope 18O to the lighter 16O. The ratio of 18O/16O stored in the foraminifera's shells depends on the water temperature. But there is also another effect that leads to relatively large amounts of 18O being found in the foraminifera's shells in glacial periods: when, during the course of a glacial period, there is heavy snowfall on land, which leads to the formation of thick ice sheets, the sea level falls - in the period studied, by as much as 120 m. Since 18O is heavier than 16O, water molecules containing this heavy isotope evaporate less readily than molecules containing the lighter isotope. As such, comparatively more 18O remains in the ocean and the 18O content of the foraminifera shells increases. 

Aerial view of the Beyond EPICA camp [Credit: Beyond EPICA]

"If you take the LR04 dataset at face value, it means you blur two effects - the influence of ocean temperature and that of land ice, or rather that of sea level change," says Peter Kohler. "This makes statements regarding the alternation of the glacial periods uncertain." And there is an additional factor: climate researchers mainly determine the sequence of glacial periods on the basis of glaciation in the Northern Hemisphere. But using 18O values doesn't allow us to say whether prehistoric glaciation chiefly occurred in the Northern Hemisphere or in Antarctica.

Computer model separates the influencing parameters

In an attempt to solve this problem, Kohler and his team evaluated the LR04 dataset in a completely different way. The data was fed into a computer model that simulates the growth and melting of the large continental ice sheets. What sets it apart: the model is capable of separating the influence of temperature and that of sea level change on the 18O concentration. Furthermore, it can accurately analyse where and when snow falls and the ice increases - more in the Northern Hemisphere or in Antarctica. "Mathematicians call this separation a deconvolution," Kohler explains, "which our model is capable of delivering." 

The results show that the sequence of glacials and interglacials was irregular even in the period 2.6 to 1.0 million years ago - a finding that could be crucial in the coming years. As part of the ongoing major EU project 'BE-OIC (Beyond EPICA Oldest Ice Core)', researchers are drilling deeper than ever before into the Antarctic ice. With the oldest ice core recovered to date, 'EPICA', they have 'only' travelled back roughly 800,000 years into the past. 

The ancient ice provides, among other things, information on how much carbon dioxide Earth's atmosphere contained at that time. With 'Beyond EPICA' they will delve circa 1.5 million years into the past. By combining the carbon dioxide measurements with Kohler's analyses, valuable insights can be gained into the relation between these two factors - the fluctuations in the sequence of glacials and the carbon dioxide content of the atmosphere. And this can help us understand the fundamental relationship between greenhouse gases and climate changes in Earth's glacial history.

Source: Alfred Wegener Institute for Polar and Marine Research [October 26, 2020]

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Evolutionary pattern of genus Cribroconcha reveals survival strategy of ostracods from late Paleozoic

Ostracods are microcrustacea that first appeared in the Ordovician and are still developing today. Although tiny, they are the most abundant fossil records of the Arthropod phylum, and the most diverse species of Crustaceans, with about 65,000 living and fossil species.

Distinct species of Cribroconcha Cooper, 1941
[Credit: NIGPAS]

Ostracods offer special insights into the characteristics of Devonian bio-environmental events. The ostracode genus Cribroconcha Cooper, 1941, is characterized by distinct morphological features, rapid evolutionary rates and wide geographical distribution, making it a potential index fossil for stratigraphic correlation and palaeoecological changes.

Recently, Dr. SONG Junjun from the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences (NIGPAS) and her colleagues made a thorough analysis of the evolutionary pattern of Cribroconcha lineages and the established biozones.

To date, 37 species and two subspecies (36 species plus one species that with two subspecies) of the ostracode genus Cribroconcha Cooper, 1941, have been reported worldwide, ranging in age from the Middle Devonian to the Early Permian with an acme during the Carboniferous.

Based on the geographical distribution and morphological characteristics of Cribroconcha, two evolutionary lineages (i.e., Lineage 1 and Lineage 2) were identified, which originated in the European and the Kazakhstan plates, respectively. Lineage 1 can be subdivided into three types: 1-A (stable type), 1-B (reshaped type) and 1-C (spiny type).

Distribution of Cribroconcha species from the Late Devonian
to the Early Permia [Credit: NIGPAS]

The researchers found that 1-A stable type species inherited the characteristics of the early species totally. The 1-B reshaped type had elongate carapaces with subrectangular outline and subquadrate posterior border. Compared with the early species, species of this type only changed in the outline. The 1-C spiny type had the longest stratigraphic range and most species of this type had two sharp spines in the posterior border.

Most species of the 1-A and 1-B are benthic and living in a shallow marine environment. Some species of 1-C are nektonic and appeared in the deep cold waters from the shelf to the basin.

Only 1-C type species extended to the Early Permian, which implies the survival strategy of spiny type was successful. The morphological variability of spiny type is also related to the glacial event across the Devonian-Carboniferous boundary in the northern Gondwana, which generated cold deep water currents invading the palaeotethysian basins.

The research results were published in the journal Palaeogeography, Palaeoclimatology, Palaeoecology.

Author: Li Yuan | Source: Chinese Academy of Sciences [October 26, 2020]

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Timeline of early eukaryotic evolution unveiled

One of the most important and puzzling events in the evolution of life has been the origin of the first complex eukaryotic cells. Almost all lifeforms that we can perceive with the naked eye, such as algae, plants, animals and fungi, are made up of complex cells known as 'eukaryotes'. A collaborative study between the groups of Toni Gabaldon, ICREA researcher at the Institute for Research in Biomedicine (IRB Barcelona) and the Barcelona Supercomputing Center (BSC-CNS), and Berend Snel at the University of Utrecht, has concluded that the first cell to incorporate a mitochondrion (considered the key step to the increased complexity of eukaryotic cells) already presented eukaryote-like complexity in structure and functions. This scenario serves as a bridge between the signs of complexity observed in some archaeal genomes and the proposed role of mitochondria in triggering eukaryogenesis.

Timeline of early eukaryotic evolution unveiled the mitochondrial acquisition occurred
in a scenario of increasing complexity [Credit: Utrecht University, IRB Barcelona]

"The acquisition of mitochondria was considered either to be the crucial first step or the last step in the development of eukaryotic cell complexity," explains Gabaldon, "our findings show that it was indeed a crucial event, but that it happened in a scenario where cell complexity had already increased."

Complexity as a prelude to the diversity of life

For roughly the first half of the history of life on Earth, the only forms of life were the relatively simple cells of bacteria. "Eukaryotic cells are larger, contain more DNA and are made up of compartments, each with their own task," explains first author Julian Vosseberg. "In that sense, you could compare bacterial cells with a tent, while eukaryotic cells are more like houses with several rooms."

How and when organisms traded the tent for a house is still a mystery, as there are no intermediate forms. One important moment in evolution was the origin of mitochondria, a component of eukaryotic cells that function as their 'power plants'. Mitochondria were once free-living bacteria, but during evolution, they were absorbed by the ancestors of today's eukaryotic cells. As gene duplication probably drove the increase in cell complexity, the researchers attempted to reconstruct the evolutionary events based on these genetic changes.

Bioinformatics for evolutionary path reconstruction

"We can use the DNA of contemporary species to reconstruct evolutionary events. Our genes were formed over aeons of evolution. They have changed dramatically over that time, but they still hold echoes of a distant past." Vosseberg adds, "We have a vast quantity of genetic material available, from a variety of organisms, and we can use computers to reconstruct the evolution of thousands of genes, including ancient gene duplications. These reconstructions have enabled us to uncover the timing of important intermediate steps."

The co-corresponding author, Berend Snel, from the University of Utrecht, says, "Scientists did not have a timeline of these events. But now we've managed to reconstruct a rough timeline." To achieve this, the researchers adapted an existing method developed at Gabaldon's lab to create a new protocol, which has resulted in novel insights. These indicate that a lot of complex cellular machinery had evolved even before the symbiosis with mitochondria, including the development of transport within the cell and the cytoskeleton. "The symbiosis wasn't an event that served as the catalyst for everything else. We observed a peak in gene duplications much earlier in time, indicating that cell complexity had already increased before that moment," says Snel.

"Our study suggests that the ancestral host that acquired the mitochondrial endosymbiont had already developed some complexity in terms of a dynamic cytoskeleton and membrane trafficking" says Gabaldon "this might have favoured the establishment of symbiotic associations with other microorganisms, including the mitochondrial ancestor, which eventually became integrated".

Source: Institute for Research in Biomedicine (IRB Barcelona) [October 26, 2020]

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Tracking the Himalayan history from the evolution of hundreds of frogs, lizards and snakes

The Himalaya are among the youngest and highest mountains in the world, but the exact timing of their uplift and origins of their biodiversity are still in debate. Generally, there are two hypotheses about the uplift process of the Himalaya. The "Stepwise Hypothesis" states that the Himalaya rose slowly from 1000-2500 m during 56-23 million years ago (Ma), before an additional rapid uplift to 4000 m during 23-19 Ma, and a final rise to the current average elevations (~5000 m) at around 15 Ma. Alternatively, recent hydrological and thermal evidences support that this region was probably not elevated to current elevation till mid-Pliocene ("Late Orogeny Hypothesis").

The Himalaya and representative amphibians and reptiles
[Credit: Science China Press]

Time-based records of biological processes can be informative about montane histories and environmental changes. Various hypotheses about Himalayan origins can be tested using phylogenetic information and estimates of the timing of biological speciation events. To address the question about the timing of the Himalaya uplift, we carried out field work across the Himalaya to collect samples of amphibians and reptiles. The Himalayan region encompasses multiple countries and has many access challenges, so sampling across the entire region is difficult, which has inhibited integrative studies of the origin of the Himalayan biota.

Combining 14 time-calibrated phylogenies of Himalayan-associated amphibian and reptile families involving 85 genera and 1628 species, we estimated times of divergence among 183 species that occur in the Himalaya. We identified 230 biogeographic events related to the Himalayan species. The dynamics of in situ diversification and dispersal rates remained essentially parallel across the Cenozoic. Both the in situ diversification rate, as well as the dispersal rate into the Himalaya, fit the Stepwise Hypothesis for the origin of this mountain range. In contrast, our estimates of origination and peak diversification are not consistent with the late-uplift hypothesis.

Biotic assembly through time of herpetofauna in the Himalaya. (a): The rates of in situ diversification
 and dispersal of the Himalayan herpetofauna through time (smoothed across 5 Ma windows).
Dispersal indicates "dispersal into the Himalaya." MDivE = maximal number of observed
 in situ diversification events per Ma. MDisE = maximal number of observed dispersal events
per Ma. Ambiguous events are separately listed. (b): Dispersal events from adjacent regions
 into the Himalaya (smoothed across 5 Ma windows). MDisE = maximal number
of observed dispersal events per Ma [Credit: Science China Press]

The rapid Himalayan uplift and associated intensified South Asia Monsoon not only promoted a pulse of uplift-driven in situ diversification, but also affected the rates of biotic interchange. Biotic interchange was restricted by the lack of a moist environment that is required by many reptiles and amphibians. In contrast, an expanded tropical forest belt is thought to have persisted between the Himalaya and Southeast Asia since the middle Miocene, which likely accounts for the high dispersal rates between these two regions.

This work has important implications about the assembly process of Himalayan herpetofauna and its conservation. Our analyses show a deep-rooted origin of Himalayan herpetofauna originating in the Paleocene, but with rapid diversification in the Miocene.

The study is published in the National Science Review 2020.

Source: South China Press [October 26, 2020]

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Hidden losses deep in the Amazon rainforest

Few places on Earth are as rich in biodiversity and removed from human influence as the world's largest rainforest -- the Amazon. Scientists at Louisiana State University (LSU) have been conducting research within the pristine rainforest for decades. However, they began to notice that some of the animals, specifically birds that forage on and near the forest floor, had become very difficult to find.

New research shows animal patterns are changing in the absence of landscape change, which signals
a sobering warning that simply preserving forests will not maintain rainforest biodiversity
[Credit: Vitek Jirinec, LSU]

"What we think is happening is an erosion of biodiversity, a loss of some of the richness in a place where we would hope biodiversity can be maintained," said LSU School of Renewable Natural Resources Professor Philip Stouffer, who is the lead author of a new study published in Ecology Letters.

Stouffer began leading field research deep within the Amazon rainforest, north of Manaus, Brazil, when he was a post-doctoral researcher with the Smithsonian in 1991. With support from the National Science Foundation, he continued to oversee bird monitoring at the Biological Dynamics of Forest Fragments Project until 2016. However, around 2008, he and his graduate students noticed that they could seldom find some bird species that they had observed in previous years.

Stouffer and his students devised a research plan to collect new data that would be directly comparable to historical samples from the early 1980s. LSU graduate students Vitek Jirinec and Cameron Rutt collaborated with Stouffer to synthesize the results, aided by the computational modeling expertise from co-author LSU Department of Oceanography & Coastal Sciences Assistant Professor Stephen Midway. The team analyzed the vast dataset that spanned more than 35 years and covered 55 sites to investigate what Stouffer and his graduate students had observed in the field.

"It's a very robust dataset from a variety of places collected over many years. It's not just some fluke. It looks like there's a real pattern and it looks like it could be linked to things we know are happening with global climate change that are affecting even this pristine place," Midway said.

This downward trend signals a shifting baseline that could have gone undetected.

"Our nostalgia was correct--certain birds are much less common than they used to be," Stouffer said. "If animal patterns are changing in the absence of landscape change, it signals a sobering warning that simply preserving forests will not maintain rainforest biodiversity."

Winners and losers

In general, the birds that have experienced the most dramatic declines live on or near the forest floor where they forage on arthropods, mostly insects. However, there is some variation among species winners and losers in the rainforest.

The iconic voice of the Amazon rainforest, the Musician Wren, is one of the birds that researchers
have discovered is on the decline in pristine, remote parts of the Amazon
[Credit: Philip Stouffer, LSU]

For example, the Wing-banded Antbird , or Myrmornis torquata, is one of the species that has declined since the 1980s. It is also one of the species that forages insects on the forest floor by searching under leaves and other debris. Also declining is the Musician Wren , or Cyphorinus arada, a seldom-seen bird with one of the iconic voices of the Amazon.

Conversely, the White-plumed Antbird , or Pithys albifrons, has not declined and remains common. Its foraging strategy may be the key to its resilience. The White-plumed Antbird follows swarms of marauding ants that churn up other insects hidden on the forest floor. The antbird jockeys for an advantageous position ahead of the ant swarm and preys upon the fleeing insects. The White-plumed Antbird is not tied to one location in the rainforest. It travels and eats a variety of prey surfaced by the swarms of ants.

The scientists also found that frugivores, or birds that also eat fruit, are increasing in abundance. This suggests that omnivorous birds with more flexible diets can adjust to changing environmental conditions.

More research is needed to better understand the hidden losses and shifting baseline that are happening in the Amazon rainforest and other parts of the planet. "The idea that things are changing, even in the most pristine parts of our planet yet we don't even know it, illustrates the need for us to pay more attention," Stouffer said.

Source: Louisiana State University [October 26, 2020]

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The uncertain future of the oceans

The ocean plays a key role in the current climate change, as it absorbs a considerable part of the atmospheric carbon dioxide emitted by mankind. On the one hand, this slows down the heating of the climate, and on the other hand, the dissolution of CO2 in seawater leads to acidification of the oceans. This has far-reaching consequences for many marine organisms and thus also for the oceanic carbon cycle. One of the most important mechanisms in this cycle, is called the biological carbon pump. Part of the biomass that phytoplankton forms in the surface ocean through photosynthesis sinks to the depths in the form of small carbonaceous particles. As a result, the carbon is stored for a long time in the deep sea. The ocean thus acts as a carbon sink in the climate system. How strongly this biological pump acts varies greatly from region to region and depends on the composition of species in the ecosystem.

One of the mesocosm experiments evaluated in the current study took place
in 2010 in Kongsfjord, Spitsbergen [Credit: Kerstin Nachtigall]

The study, which has now been published in the journal Nature Climate Change, is one of the most comprehensive studies so far on the effects of ocean acidification on marine ecosystems. Scientists at the GEOMAR Helmholtz Centre for Ocean Research in Kiel have now been able to show for the first time that ocean acidification influences the carbon content of sinking organic material, and thus the biological pump. Surprisingly, the observed changes were highly variable. The carbon content of sinking particles increased or decreased significantly with increasing CO2, depending on the composition of species and the structure of the food web. Since the underlying data cover a wide range of ocean regions, this seems to be a global phenomenon. These findings allow a completely new assessment of the effects of ocean acidification.

Dr. Jan Taucher, marine biologist and main author of the study, says: "Interestingly, we found that bacterial and animal plankton, such as small crustaceans, play a key role in how the carbon cycle and biological pump respond to ocean acidification. Until now, it has been widely held that biogeochemical changes are mainly driven by reactions of phytoplankton. Therefore, even modern Earth system models do not take into account the interactions we observe between the marine food web and the carbon cycle. Our findings thus help to make climate models more realistic and improve climate projections".

Up to now, most of the knowledge on this topic has been based on idealized laboratory experiments, which only represent ecological interactions and the dynamics of the complex marine food web in a highly simplified way. This makes it difficult to transfer such results to real ocean conditions and project them into the future. In order to gain a more realistic insight, the study summarizes several field experiments that were conducted with large-volume test facilities, so-called mesocosms, in different ocean regions, from arctic to subtropical waters.

Mesocosms are, so to speak, oversized test tubes in the ocean, in which changes in environmental conditions in a closed but otherwise natural ecosystem can be studied. For the present study, a large amount of data from five mesocosm experiments was synthesized to provide a more precise picture of plankton communities and biogeochemical processes within the ecosystem. A total of over ten thousand data points were included in the analysis.

The newly gained knowledge can now be used to implement the complex ecological interactions in Earth system models, thus contributing to further improve climate projections.

Source: GEOMAR Helmholtz Centre for Ocean Research Kiel [October 26, 2020]

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Data reveals evidence of molecular absorption in the atmosphere of a hot Neptune

An international team of scientists recently measured the spectrum of the atmosphere of a rare hot Neptune exoplanet, whose discovery by NASA's Transiting Exoplanet Survey Satellite (TESS) was announced just last month.

This artist's impression shows the LTT9779 system approximately to scale, with the hot Neptune-sized
 planet at left and its bright, nearby star at right. The trail of material streaming off of the planet
is hypothetical but likely, based on the intense irradiation of this planet
[Credit: Ethen Schmidt, Kansas University]

The discovery was made with data provided from the now-retired NASA Spitzer Space Telescope, which allows a unique, infrared view of the universe to look into regions of space that are hidden from optical telescopes.

One of the main goals of NASA's TESS mission is to find new, small planets that would be good targets for atmospheric characterization. Early in its mission, it found LTT9779b, a planet orbiting a Sun-like star located 260 light years away from Earth. This planet, a little larger than Neptune, orbits very close to its star. The planet is found in the "hot Neptune desert," where planets shouldn't exist. Indeed, most close-in hot exoplanets are either gas giants the size of Jupiter or Saturn that have enough mass to retain most of their atmosphere using their high gravity against the evaporation caused by the star, or small rocky exoplanets that have lost their atmosphere to the star long ago.

This artist's impression shows LTT9779b near the star it orbits, and highlights the planet's
ultra-hot (2000 Kelvin) day-side and its quite-toasty night-side (around 1000 K)
[Credit: Ethen Schmidt, Kansas University]

"This ultra-hot Neptune is a 'medium-sized' exoplanet that orbits very close to its star (it takes just 19 hours to complete an orbit), but its low density indicates that it still has an atmosphere weighing at least 10 percent of the planet's mass," explained University of New Mexico Physics and Astronomy Assistant Professor Diana Dragomir, who is leading the work which involved more than 25 institutions.

The age of this system is 2 billion years. At this high temperature, the planet's atmosphere should have evaporated long ago, early in the system's life. "Hot Neptunes are rare, and one in such an extreme environment as this one is difficult to explain because its mass isn't large enough to hold on to an atmosphere for very long. So how did it manage? LTT9779b had us scratching our heads, but the fact that it has an atmosphere gives us a rare way to investigate this type of planet, so we decided to probe it with another telescope," Dragomir added.

This artist's impression shows LTT9779b transiting the star it orbits. This transit briefly blocks
an appreciable fraction of the star's light, and is how the planet was first discovered
by NASA's TESS mission [Credit: Ethen Schmidt , Kansas University]

To investigate its atmospheric composition and shed further light on its origin, scientists obtained secondary eclipse observations with the Spitzer Infrared Array Camera (IRAC) of the hot Neptune. The Spitzer observations confirmed an atmospheric presence and enabled a measurement of the planet's very high temperature, approximately 2,000 Kelvin (about 3,000 degrees Fahrenheit). "For the first time, we measured light coming from a planet that shouldn't exist!" Said Dragomir.

After combining the Spitzer observations with a measurement of the secondary eclipse in the TESS bandpass, the scientists studied the resulting emission spectrum and identified evidence of molecular absorption in the planet's atmosphere, which they believe is likely due to carbon monoxide. This molecule is not unexpected in the atmospheres of hot large planets (hot Jupiters), but to find it in a hot Neptune may provide clues on the origin of this planet and how it managed to hold onto its atmosphere. This result constitutes the first detection of atmospheric features in an exoplanet discovered by TESS, and the first-ever for an ultra-hot Neptune.

"If there's a lot of atmosphere surrounding the planet, as is the case for LTT9779b, then you can study it more easily," said Dragomir. "A smaller atmosphere would be much harder to observe." The results indicate that LTT9779b is an excellent target for additional characterization with NASA's upcoming James Webb Space Telescope (JWST), which could also verify whether the observed molecular absorption is indeed due to carbon monoxide.

A companion paper, led by Kansas University Assistant Professor Ian Crossfield, also found signs that point to the planet's atmosphere having a higher level of heavy elements than expected. This is additionally intriguing because the two similarly-sized planets in our Solar System, Neptune and Uranus, are primarily composed of light elements like hydrogen and helium.

"LTT9779 is one of those super-exciting targets, a very rare gemstone for our understanding of hot Neptunes. We believe we detected carbon-monoxide in its atmosphere and that the permanent dayside is very hot, while very little heat is transported to the night side," said Bjorn Benneke, professor at Universite de Montreal and member of the Institute for Research on exoplanets (iREx). "Both findings make LTT9779b say that there is a very strong signal to be observed making the planet a very intriguing target for future detailed characterization with JWST."

Together, these results set the stage for similar investigations of a larger sample of exoplanets discovered in this hot Neptune desert, which are key to uncovering the origin of this unique population of exoplanets.

The research was published in The Astrophysical Journal Letters.

Source: University of New Mexico [October 26, 2020]

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