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Big planets get a head start in pancake-thin nurseries –

Big planets get a head start in pancake-thin nurseries
Images of the Oph163131 disk as seen by ALMA (left) and HST (right). The limits of the millimeter-sized particles in the disk observed by ALMA are outlined in white. They are concentrated in a much narrower layer than the finer (micron-sized) dust observed by the Hubble Space Telescope. Credit: ALMA (ESO/NAOJ/NRAO) /Hubble/NASA/ESA /M. Villenave

Super-thin planet nurseries have a boosted chance of forming big planets, according to a study announced this week at the Europlanet Science Congress (EPSC) 2022 in Granada, Spain. An international team, led by Dr. Marion Villenave of NASA Jet Propulsion Laboratory (JPL), observed a remarkably thin disk of dust and gas around a young star, and found that its structure accelerated the process of grains clumping together to form planets.

“Planets only have a limited opportunity to form before the disk of gas and dust, their nursery, is dissipated by radiation from their . The initial micron-sized particles composing the disk must grow rapidly to larger millimeter-sized grains, the building blocks of . In this thin disk, we can see that the large particles have settled into a dense midplane, due to the combined effect of stellar gravity and interaction with the gas, creating conditions that are extremely favorable for planetary growth,” explained Dr. Villenave.

Using the Atacama Large Millimeter Array (ALMA) in Chile, the team obtained very high resolution images of the proto-planetary disk Oph163131, located in a nearby star-forming region called Ophiuchus. Their observations showed that, while disk is twice the diameter of our Solar System, at its outer edge the bulk of the dust is concentrated vertically in a layer only half the distance from Earth to the Sun. This makes it one of the thinnest planetary nurseries observed to date.

“Looking at proto-planetary disks edge-on gives a clear view of the vertical and radial dimensions, so that we can disentangle the dust evolution processes at work,” said Villenave. “ALMA gave us our first look at the distribution of millimeter-sized grains in this disk. Their concentration into such a was a surprise, as previous Hubble Space Telescope (HST) observations of finer, micron-sized particles showed a region extending almost 20 times higher.”

Simulations by the team based on the observations show that the seeds of gas-giant planets, which must be at least 10 Earth-masses, can form in the outer part of the disk in less than 10 million years. This is within the typical lifetime of a planetary nursery before it dissipates.

“Thin planet nurseries appear to be favorable for forming big planets, and may even facilitate planets forming at large distance from the central star,” said Villenave. “Finding further examples of these thin disks might help provide more insights into the dominant mechanisms for how wide-orbit planets form, a field of research where there are still many open questions.”

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What keeps plant roots growing toward gravity? Study identifies four genes –

What happens belowground in a corn field is easy to overlook, but corn root architecture can play an important role in water and nutrient acquisition, affecting drought tolerance, water use efficiency, and sustainability. If breeders could encourage corn roots to grow down at a steeper angle, the crop could potentially access important resources deeper in the soil.

A first step toward that goal is learning the genes involved in gravitropism and root growth in response to gravity. In a new study published in the Proceedings of the National Academy of Sciences, University of Wisconsin scientists, in collaboration with researchers at the University of Illinois, identify four such genes in corn and the model plant Arabidopsis.

When a germinating seed is turned on its side, some roots make a sudden, steep turn towards gravity, while others turn a fraction more slowly. The researchers used machine vision methods to observe subtle differences in root gravitropism in thousands of seedlings and combined that data with genetic information for each seedling. The result mapped the likely positions of gravitropism genes in the genome.

The map got the researchers to the right neighborhood in the genome – regions of a few hundred genes – but they were still a long way from identifying specific genes for gravitropism. Fortunately, they had a tool that could help.

Relevant genetics
“Because we had previously performed the same experiment with the distantly related Arabidopsis plant, we were able to match genes within the relevant regions of the genome in both species. Follow-up tests verified the identity of four genes that modify root gravitropism. The new information could help us understand how gravity shapes root system architectures,” says Edgar Spalding, professor in the Department of Botany at the University of Wisconsin and lead author of the study.

Matt Hudson, professor in the Department of Crop Sciences at the University of Illinois and study co-author, adds, “We looked at an under-researched trait in maize that is important for a number of reasons, especially in the context of climate change. And we did it by making the evolutionary differences between plants work in our favor.”

Corn and Arabidopsis, a small mustard relative, exhaustively described by plant biologists, evolved about 150 million years apart in evolutionary history. Hudson explains that although both species share basic plant functions, the genes controlling them have likely been jumbled within the genome over time. That turns out to be a good thing for narrowing down common genes.

In closely related species, genes tend to line up in approximately the same order in the genome (e.g., ABCDEF). Although the same genes might exist in distantly related species, the order of genes in the region the trait maps to doesn’t match (e.g., UGRBZ). After the researchers identified where to look in each genome, the otherwise mismatched gene sequences made the common genes (in this case, B) pop out.

“I thought it was super cool that we could identify genes we wouldn’t have found otherwise just by comparing genomic intervals in unrelated plant species,” Hudson says. “We were pretty confident they were the right genes when they popped right out of this analysis, but Spalding’s group then spent seven or eight more years getting solid biological data to verify they do, indeed, play a role in gravitropism. Having done that, I think we’ve validated the whole approach so that you could use this method for many different phenotypes in the future.”

Spalding notes the method was probably particularly successful because precise measurements were made in a common environment.

“Often, maize researchers will measure their traits of interest in a field, whereas Arabidopsis researchers tend to raise their plants in growth chambers,” he says. “We measured the root gravitropism phenotype in a highly controlled way. These seeds were grown on a petri dish, and the assay lasted just hours, as opposed to traits you might measure in the real world that are open to all sorts of variabilities.”

Even when traits can be measured in a common environment, not all traits make good candidates for this method. The researchers emphasize traits in question should be fundamental to basic plant function, ensuring the same ancient genes exist in unrelated species. 

“Gravitropism may be especially amenable to study through this approach because it would have been key to the original specialization of shoots and roots after the successful colonization of land,” Spalding says.

Hudson notes gravitropism will be key to the colonization of a different landscape, as well.

“NASA is interested in growing crops on other planets or in space, and they need to know what you’d have to breed for to do that,” he says. “Plants are pretty discombobulated without gravity.”

For more information:
University of Illinois

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Brand New Scarlet & Violet Pokémon Revealed, And It’s A Floppy One – Kotaku


The sadly low-res video shows the little beasties popping their heads out of the sand on the beach, implying we’ve got at least a Water-type here. Multi-lingual discussion during the video has Pokécologists (everyone start using this term) question whether it’s related to Diglett, but then conclude that no, it’s a whole new species of Pokémon.


Goodness knows what is going on in that video, with the Wingulls seemingly stuck in the air, and the background looking like it’s running on GBA.

This makes it the 16th new Pokémon unique to the Paldean region to be revealed, ahead of November’s release of Pokémon Scarlet and Violet. Most of which have been utterly bonkers.


Generally when The Pokémon Company reveals a new creature, we get a hint dropped like this, and then a nice press release packed with information. So be sure to check back later for an update on this post with all that extra news.


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Russia’s Alrosa discovers 22 new diamond deposits in Zim – Mnangagwa – New

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By Bloomberg News

Russian miner Alrosa PSJC has discovered 22 new diamond deposits in Zimbabwe, according to the southern African nation’s president, Emmerson Mnangagwa.

Alrosa will only be allowed to work on two of the diamond deposits, while the rest will be made available to other investors, Zimbabwe’s Information Ministry said, citing comments by Mnangagwa in New York at the weekend. The president attended a business meeting on the sidelines of the United Nations General Assembly.

The Russian company declined an emailed request for comment.

In 2019, Alrosa signed an agreement with the state-owned Zimbabwe Mining Development Corp. to jointly explore for gems in the country. At the time, the company said it would spend $12 million exploring some of the 40 diamond mining rights it holds in the country.

Many in the diamond industry refuse to deal in Russian gems following the invasion of Ukraine and after mining giant Alrosa was hit with US sanctions.

After returning to Zimbabwe on Tuesday, Mnangagwa said there was interest from US-based investors in a number of sectors including mining and agriculture. A group of those investors will come to the country next month to look at opportunities, the state-owned Zimbabwe Broadcasting Corp. reported.

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