Wednesday, August 13, 2025

 SPACE/COSMOS


'Ariane 6 is a launcher for European sovereignty'


Issued on: 13/08/2025 FRANCE24



The Ariane 6 rocket on Wednesday blasted off carrying Europe's next generation satellite for warning against extreme weather events. As many European countries simmer in a deadly heatwave, the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) said its MetOp-SGA1 satellite will give "earlier warnings to help protect lives and property from extreme weather". Oliver Farry welcomes Olivier Sanguy, Editor-in-Chief of Space News, joins us from Cité de l’Espace in Toulouse, France.It's a new kind of satellite


Video by:
Oliver FARRY    

Auction of world’s largest Mars meteorite sparks ownership debate


By AFP
August 12, 2025


The 54-pound Martian meteorite NWA 16788, the largest known piece of Mars ever discovered on Earth, was sold for a record $5.3 million at Sotheby's New York - Copyright AFP Frederic DIDES
Charlotte CAUSIT

The recent auction of a Martian meteorite — for a record-grabbing $5.3 million at Sotheby’s New York — has sparked questions over its provenance and renewed debate over who gets to claim rocks fallen from the heavens.

The hefty 54-pound (25-kilogram) stone is the largest Martian meteorite ever discovered on Earth, according to its Sotheby’s listing, and was found in November 2023 in the vast Saharan desert in Niger.

The government of Niger has announced that it will open an investigation following the auction, saying it appears to “have all the characteristics of illicit international trafficking.”

On Friday, the government suspended exports of precious stones and meteorites until further notice.

Sotheby’s has rejected the accusations, insisting that the meteorite was “was exported from Niger and transported in line with all relevant international procedure.”

In light of the controversy, however, a review of the case is underway, a Sotheby’s spokesperson told AFP.

“The stone journeyed 140 million miles through space, and hurtled through Earth’s atmosphere before crashing in the Sahara Desert,” the Sotheby’s listing said.

Following its discovery, the jagged, ochre-colored stone was then sold to an international dealer, briefly exhibited in Italy, and eventually ended up in the auction catalog in New York.

For American paleontologist Paul Sereno, who has worked closely with Niger’s authorities for years, all signs suggest that the stone left the country “illicitly.”

“Everybody’s anonymous — from the person who found it, the dealers, the guy who bought it, everybody’s anonymous,” he told AFP, making no secret of his frustration.

“If they had put on baseball gloves and caught the meteorite as was hurtling towards Earth before it landed in any country, they could claim it… but I’m sorry, it landed there. It belongs to Niger,” he said.



– ‘We should respect it’ –



Laws governing the ownership of meteorites vary based on their point of impact.

In the United States, for example, if a rock falls on private land, the property owners have ownership rights.

In Niger, however, a law governs “national cultural patrimony,” which includes rare mineralogical specimens, according to Matthieu Gounelle, a professor at France’s National History Museum, and his father Max Gounelle, a French university professor.

Both are specialists in regulations governing the collection and sale of meteorites.

“In our opinion, there is no doubt that meteorites should be included among the rare mineralogical specimens” protected by Nigerien law, they told AFP.

Beyond the legal battle and the possible involvement of a trafficking network, the sale of the meteorite also raises science ethics questions.

The rock, named NWA 16788, has unique scientific research value.

Much larger than other Martian meteorites that have been recorded to date, it offers a unique insight into the geological history of the Red Planet.

Like other Martian meteorites, it is believed to have been ejected into space when an asteroid slammed into Mars.

“This is nature’s heritage. In many ways, it’s world heritage, and it’s telling us things about the cosmos. We should respect it,” Sereno said.

“It’s not something to my mind that should be auctioned up to potentially disappear into someone’s mantle.”

burs-cha/des/jgc


Early galaxies — or something else? Mizzou scientists uncover mysterious objects in the universe


Using data from NASA’s James Webb Space Telescope, University of Missouri researchers identified 300 unusual early galaxy candidates



University of Missouri-Columbia

Galaxy graphic 

image: 

Graphic showing the mysterious objects in the universe that the University of Missouri researchers identified.in their study.

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Credit: Bangzheng “Tom” Sun/University of Missouri





In a new study, scientists at the University of Missouri looked deep into the universe and found something unexpected. Using infrared images taken from NASA’s powerful James Webb Space Telescope (JWST), they identified 300 objects that were brighter than they should be.

“These mysterious objects are candidate galaxies in the early universe, meaning they could be very early galaxies,” said Haojing Yan, an astronomy professor in Mizzou’s College of Arts and Science and co-author on the study. “If even a few of these objects turn out to be what we think they are, our discovery could challenge current ideas about how galaxies formed in the early universe — the period when the first stars and galaxies began to take shape.”

But identifying objects in space doesn’t happen in an instant. It takes a careful step-by-step process to confirm their nature, combining advanced technology, detailed analysis and a bit of cosmic detective work.

Step 1: Spotting the first clues

Mizzou’s researchers started by using two of JWST’s powerful infrared cameras: the Near-Infrared Camera and the Mid-Infrared Instrument. Both are specifically designed to detect light from the most distant places in space, which is key when studying the early universe.

Why infrared? Because the farther away an object is, the longer its light has been traveling to reach us.

“As the light from these early galaxies travels through space, it stretches into longer wavelengths — shifting from visible light into infrared,” Yan said. “This stretching is called redshift, and it helps us figure out how far away these galaxies are. The higher the redshift, the farther away the galaxy is from us on Earth, and the closer it is to the beginning of the universe.”

Step 2: The ‘dropout’

To identify each of the 300 early galaxy candidates, Mizzou’s researchers used an established method called the dropout technique.

“It detects high-redshift galaxies by looking for objects that appear in redder wavelengths but vanish in bluer ones — a sign that their light has traveled across vast distances and time,” said Bangzheng “Tom” Sun, a Ph.D. student working with Yan and the lead author of the study. “This phenomenon is indicative of the ‘Lyman Break,’ a spectral feature caused by the absorption of ultraviolet light by neutral hydrogen. As redshift increases, this signature shifts to redder wavelengths.”

Step 3: Estimating the details

While the dropout technique identifies each of the galaxy candidates, the next step is to check whether they could be at “very” high redshifts, Yan said.

“Ideally this would be done using spectroscopy, a technique that spreads light across different wavelengths to identify signatures that would allow an accurate redshift determination,” he said.

But when full spectroscopic data is unavailable, researchers can use a technique called spectral energy distribution fitting. This method gave Sun and Yan a baseline to estimate the redshifts of their galaxy candidates — along with other properties such as age and mass.

In the past, scientists often thought these extremely bright objects weren’t early galaxies, but something else that mimicked them. However, based on their findings, Sun and Yan believe these objects deserve a closer look — and shouldn’t be so quickly ruled out.

“Even if only a few of these objects are confirmed to be in the early universe, they will force us to modify the existing theories of galaxy formation,” Yan said.

Step 4: The final answer

The final test will use spectroscopy — the gold standard — to confirm the team’s findings.

Spectroscopy breaks light into different wavelengths, like how a prism splits light into a rainbow of colors. Scientists use this technique to reveal a galaxy’s unique fingerprint, which can tell them how old the galaxy is, how it formed and what it’s made of.

“One of our objects is already confirmed by spectroscopy to be an early galaxy,” Sun said. “But this object alone is not enough. We will need to make additional confirmations to say for certain whether current theories are being challenged.’’ 

The study, “On the very bright dropouts selected using the James Webb Space Telescope NIRCam instrument,” was published in The Astrophysical Journal.

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