Sea star’s ability to clone itself may empower this mystery globetrotter — ScienceDaily

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For decades, biologists have captured tiny sea star larvae in their nets that did not match the adults of any known species. A Smithsonian team recently discovered what these larvae grow up to be and how a special superpower may help them move around the world. Their results are published online in the Biological Bulletin.

“Thirty years ago, people noticed that these asteroid starfish larvae could clone themselves, and they wondered what the adult form was,” said staff scientist Rachel Collin at the Smithsonian Tropical Research Institute (STRI). “They assumed that because the larvae were in the Caribbean the adults must also be from the Caribbean.”

Scientists monitor larvae because the larvae can be more sensitive to physical conditions than the adults and larval dispersal has a large influence on the distribution of adult fishes and invertebrates. Collin’s team uses a technique called DNA barcoding to identify plankton. They determine the DNA sequence of an organism, then look for matches with a sequence from a known animal in a database.

“This mystery species was one of the most common in our samples from the Caribbean coast of Panama,” Collin said. “We knew from people’s studies that the DNA matched sequences from similar larvae across the Caribbean and it matched unidentified juvenile starfish caught in the Gulf of Mexico — but no one had found a match to any known adult organism in the Caribbean. So we decided to see if the DNA matched anything in the global ‘Barcode of Life’ data base.”

“That’s when we got a match with Valvaster striatus, a starfish that was thought to be found only in the Indo West Pacific,” Collin said. “The is the first-ever report of this species in the Atlantic Ocean. We could not have identifed it if Gustav Paulay

Modelling extreme magnetic fields and temperature variation on distant stars

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IMAGE

IMAGE: The maps show the heat distribution. The bue regions are cooler – and the yellow regions are hotter.

It describes data taken from the following magentars: 4U 0142+61, 1E 1547.0-5408, XTE…
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Credit: University of Leeds

New research is helping to explain one of the big questions that has perplexed astrophysicists for the past 30 years – what causes the changing brightness of distant stars called magnetars.

Magnetars were formed from stellar explosions or supernovae and they have extremely strong magnetic fields, estimated to be around 100 million, million times greater than the magnetic field found on earth.

The magnetic field generates intense heat and x-rays. It is so strong it also affects the physical properties of matter, most notably the way that heat is conducted through the crust of the star and across its surface, creating the variations in brightness across the star which has puzzled astrophysicists and astronomers.

A team of scientists – led by Dr Andrei Igoshev at the University of Leeds – has developed a mathematical model that simulates the way the magnetic field disrupts the conventional understanding of heat being distributed uniformly and creates hotter and cooler regions where there may be a difference in temperature of one million degrees Celsius.

Those hotter and cooler regions emit x-rays of differing intensity – and it is that variation in x-ray intensity that is observed as changing brightness by space-borne telescopes.

The findings are published today (12 October) in the journal Nature Astronomy. The research was funded by the Science and Technology Facilities Council (STFC).

Dr Igoshev, from the School of Mathematics at Leeds, said: “We see this constant pattern of hot and cold regions. Our model – based on the physics of magnetic fields and the physics of heat – predicts the

Rare Peacock Stars Could Potentially Detonate Deadly Gamma Rays In The Milky Way [Video]

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KEY POINTS

  • Gamma-ray bursts are one of the most energetic occurrences in the universe
  • Apep’s two stars are 10 to 15 times more massive and 100,000 times brighter than the Sun
  • The two stars also orbit each other about every 125 years

Apep, one of the Wolf-Rayets binary star systems dubbed as the “exotic peacocks of the stellar world” discovered in 2018, was found to have the capacity to detonate long gamma ray bursts that are potentially deadly. If it detonates, the explosion could be something never seen in the Milky Way before, according to scientists.

“As well as exhibiting all the usual extreme behavior of Wolf-Rayets, Apep’s main star looks to be rapidly rotating. This means it could have all the ingredients to detonate a long gamma-ray burst when it goes supernova,” Peter Tuthill, study lead and professor from the University of Sydney, said in a press release. 

In the study published in the Monthly Notices of the Royal Astronomical Society, the team explained that gamma-ray bursts are one of the most energetic occurrences in the universe, adding that “they are potentially deadly.” 

If the detonation happens on Earth, for instance, the explosion can destroy the ozone layer, exposing everyone and everything to the sun’s ultraviolet radiation. The scientists clarify that Apep’s axis of rotation is far from Earth and won’t affect humans when an explosion happens in the future.  

Apep, a binary star system that is 8,000 light-years from Earth, was classified as a Wolf-Rayet two years ago. Being categorized as a Wolf-Rayet is already rare. Only a handful of stars made the cut to be categorized as one. Their temperatures are so hot that they collapse in a supernova explosion faster than the ordinary stars.   

In the case of Apep, it is also recognized as one of

In Stars of Science First, Jury Decides No Elimination

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DOHA, Qatar, Oct. 11, 2020 /PRNewswire/ — For the first time in the history of Qatar Foundation’s Stars of Science, the jury agreed to advance all top eight contestants in the concept prototyping episode to the next phase – displaying the TV show’s commitment to scientific integrity and fairness.

In Stars of Science First, Jury Decides No Elimination

To view the Multimedia News Release, please click: https://www.multivu.com/players/uk/8793251-in-stars-of-science-first-no-elimination/

Dr. Khalid Al-Ali, Stars of Science jury member, noted that the show’s contestants ran into unprecedented circumstances with the outbreak of COVID-19, causing disproportionate difficulties in materials procurement and shipping delays.

“Exceptional times necessitate exceptional action. We, the jury members of Stars of Science, place fairness firmly on top of the show’s platform of opportunity. We work hard to give the contestants a level playing field in order for the best to truly excel,” said Dr. Al-Ali.

During the proof of concept episode, several contestants laid out a roadmap for the next stages of the competition. However, COVID-19 hampered some contestants’ progress, as they did not have the necessary resources to start proving the concept of their innovation. Jamal Shaktour was among the most affected, as crucial supplies from abroad did not arrive in time for the jury’s review.

“These exceptional times pushed all of us to adapt to the new norms dictated by the pandemic, as we had to work with what we had available and persevere,” said Shaktour. “The jury’s decision is a golden opportunity to all of us and is a push to motivate us even further, prove ourselves, and shine.”

This episode witnessed the return of Majed Lababidi, who competed during Season 3 in 2011, as a co-host alongside the show’s long-time presenter, Khalid Al Jumaily. Lababidi is an example of the show’s strong track record of empowering young Arab minds

AI Created a Detailed 3D Map of Stars, Galaxies, and Quasars

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Pan-STARRS telescope in Hawai’i

Pan-STARRS telescope in Hawai’i
Image: University of Hawai’i

A team of astronomers from the University of Hawaiʻi at Mānoa’s Institute for Astronomy (IfA) has produced the most comprehensive astronomical imaging catalog of stars, galaxies, and quasars ever created with help from an artificially intelligent neural network.

The group of astronomers from the University of Hawaiʻi at Mānoa’s Institute for Astronomy (IfA) released a catalog containing 3 billion celestial objects in 2016, including stars, galaxies, and quasars (the active cores of supermassive black holes). Needless to say, the parsing of this extensive database—packed with 2 petabytes of data—was a task unfit for puny humans, and even grad students. A major goal coming out of the 2016 catalog release was to better characterize these distant specks of light, and to also map the arrangement of galaxies in all three dimensions. The Pan-STARRS team can now check these items off their to-do list, owing to the powers of machine learning. The results of their work have been published to the Monthly Notices of the Royal Astronomical Society.

Their PS1 telescope, located on the summit of Haleakalā on Hawaii’s Big Island, is capable of scanning 75% of the sky, and it currently hosts the world’s largest deep multicolor optical survey, according to a press release put out by the University of Hawaiʻi. By contrast, the Sloan Digital Sky Survey (SDSS) covers just 25% of the sky.

Density map of the universe, for galaxies between 1.5 and 3 billion light years away.

Density map of the universe, for galaxies between 1.5 and 3 billion light years away.
Image: University of Hawai’i

To provide the computer with a frame of reference, and to teach it how to discern celestial classes of objects from one another, the team turned to publicly available spectroscopic measurements. These measures of colors and sizes of objects numbered in the millions, as Robert