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NASA to roll back its mega rocket after failing to complete countdown test – Ars Technica

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Enlarge / The Space Launch System rocket rolls out of the Vehicle Assembly Building in mid-March, 2022.
Trevor Mahlmann

After three attempts to complete a critical fueling test of the Space Launch System rocket, NASA has decided to take a break.

On Saturday night the space agency announced plans to roll the large SLS rocket from the launch pad at Kennedy Space Center to the Vehicle Assembly Building in the coming days. This marks a notable step back for the program, which has tried since April 1 to complete a “wet dress rehearsal” test, during which the rocket is fueled and brought to within 10 seconds of launch.

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The decision comes after three tries during the last two weeks. Each fueling attempt was scuttled by one or more technical issues with the rocket, its mobile launch tower, or ground systems that supply propellants and gases. During the most recent attempt, on Thursday April 14, NASA succeeded in loading 49 percent of the core-stage liquid oxygen fuel tank and 5 percent of the liquid hydrogen tank.

While this represents progress, it did not include the most dynamic portion of the test, during which the rocket is fully fueled and pressurized; and it, the ground systems, and computer systems are put into a terminal countdown when every variable is closely monitored. NASA had hoped to complete this wet dress rehearsal test to work out the kinks in the complicated launch system so that, when the rocket is rolled out later this year for its actual launch, the countdown will proceed fairly smoothly.

NASA said that its contractors, as well as its agency’s, will use the next several weeks to address problems that cropped up during the fueling tests when the SLS rocket returns to the large Vehicle Assembly Building. For example, gaseous nitrogen system supplier Air Liquide will upgrade its capabilities. NASA will also replace a faulty check valve on the upper stage of the rocket, as well as fix a leak on the mobile launch tower’s “tail service mast umbilical,” a 10-meter-tall structure that provides propellant and electricity lines to the rocket on the pad.

The space agency announcement did not provide any information about schedule impacts. It seems probable that it will take a week or so to prepare and roll the SLS rocket back to the Vehicle Assembly Building. Work on the rocket at that location will probably take up most of the month of May, at least.

NASA will then have to make some difficult decisions. It could opt to roll the rocket and its mobile launch tower to the pad a second time and try again to complete the wet dress rehearsal test. Then, following its normal procedure, NASA would roll the rocket back to its assembly building to arm the “flight safety system,” before rolling for a third time to the launch pad for liftoff. It seems the absolute earliest the SLS rocket could launch in such a scenario would be August, but a fall liftoff may be more likely.

Another option NASA could pursue is to roll-out, complete a wet-dress test on the pad, and then if that is successful, to go ahead and launch within a few days. Under such a scenario NASA might be able to launch the SLS rocket in June or July. However, this would be risky due to the flight safety system.

During a teleconference on Friday, Artemis Launch Director Charlie Blackwell-Thompson confirmed that there is a 20-day timeline once the flight safety system is armed. (This is a range safety mechanism used by all orbital rockets that destroys the booster in case it veers off course.) After the system is activated, it will take about a week to make final preparations in the Vehicle Assembly Building and a week to roll to the launch pad and make preparations there. That would leave just a single week for a fueling test, recycling of commodities, and perhaps one or two launch attempts before the 20-day window closes.

In other words, this means the wet dress test would have to be nearly flawless, and then the launch attempt would need to be flawless as well. It would also mean that summertime weather in Florida—when there are numerous thunderstorms and other inclement conditions—would have to cooperate.

Finally, NASA engineers must weigh a host of other factors, such as wear and tear on the rocket, its side-mounted boosters being exposed outside, as well as seemingly innumerable lifetime considerations with the hardware. For example, agency officials are closely tracking the health of the fuel in the solid-rocket boosters, which were stacked about 16 months ago, among other issues.

Still, NASA seems confident that it will get through this painful teething process for the SLS rocket: a program that is now 11 years old and in which NASA has invested more than $30 billion in the rocket and ground systems now being tested.

“There’s no doubt in my mind that we will finish this test campaign, and we will listen to the hardware, and the data will lead us to the next step,” Blackwell-Thompson said Friday. “And we will take the appropriate steps, and we will launch this vehicle. I don’t know exactly what that date is, but there’s no doubt in my mind that we’ll finish the test campaign, and we will be ready to go fly.”

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Scientists claim evidence of 'Planet 9' in our solar system – Supercar Blondie

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A team of scientists claims to have evidence that there is another hidden planet – nicknamed ‘Planet 9’ – lurking in our solar system.

Of course, there have been changes to the number of planets in our solar system over recent – in space terms, anyway – years, as Pluto is no longer considered a proper planet.

Seems a bit harsh, doesn’t it?

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However, a team of astronomers now believe that they have the strongest evidence yet that there is another mysterious planet hovering around our sun.

READ MORE! James Webb Telescope observes light on Earth-like planet for the first time in history

The theory that there could be other planets orbiting our star has been around for years, as scientists have noticed some unusual phenomena on the edge of the solar system that suggest the existence of another celestial body.

The theory that another planet is responsible would also explain the orbit of other objects that are outliers in our system, sitting more than 250 times Earth’s distance from the sun.

Scientist Konstantin Bogytin and his team have long been proponents of this ‘Planet 9’ theory, and now they believe they have ‘the strongest statistical evidence yet that Planet 9 is really out there’.

As we know, it wouldn’t be the only strange thing in our solar system.

Or outside, for that matter.

Perhaps they just need to point a massive space telescope at it and they’ll find evidence of alien life out there.

This new study by Bogytin and his team focused on a number of Trans-Neptunian Objects (TNOs) that lie outside the orbit of Neptune towards the outer reaches of our solar system.

In analyzing the movements of these objects – which can be affected by the orbit of Neptune, as well as passing stars and the ‘galactic tide’ – the scientists concluded that there could be another unseen planet out there.

Dr Bogytin pointed out that there are other potential explanations for the behavior of these objects, but – he believes – Planet 9 is the best bet.

Once the Vera C. Rubin Observatory in Chile becomes active, we might get the best look we’ve had yet.

In a paper, the team wrote: “This upcoming phase of exploration promises to provide critical insights into the mysteries of our solar system’s outer reaches.”

That paper, entitled ‘Generation of Low-Inclination, Neptune-Crossing TNOs by Planet Nine’ is available to read here.

Images in this article were generated using AI

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Marine plankton could act as alert in mass extinction event: UVic researcher – Saanich News

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A University of Victoria micropaleontologist found that marine plankton may act as an early alert system before a mass extinction occurs.

With help from collaborators at the University of Bristol and Harvard, Andy Fraass’ newest paper in the Nature journal shows that after an analysis of fossil records showed that plankton community structures change before a mass extinction event.

“One of the major findings of the paper was how communities respond to climate events in the past depends on the previous climate,” Fraass said in a news release. “That means that we need to spend a lot more effort understanding recent communities, prior to industrialization. We need to work out what community structure looked like before human-caused climate change, and what has happened since, to do a better job at predicting what will happen in the future.”

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According to the release, the fossil record is the most complete and extensive archive of biological changes available to science and by applying advanced computational analyses to the archive, researchers were able to detail the global community structure of the oceans dating back millions of years.

A key finding of the study was that during the “early eocene climatic optimum,” a geological era with sustained high global temperatures equivalent to today’s worst case global warming scenarios, marine plankton communities moved to higher latitudes and only the most specialized plankton remained near the equator, suggesting that the tropical temperatures prevented higher amounts of biodiversity.

“Considering that three billion people live in the tropics, the lack of biodiversity at higher temperatures is not great news,” paper co-leader Adam Woodhouse said in the release.

Next, the team plans to apply similar research methods to other marine plankton groups.

Read More: Global study, UVic researcher analyze how mammals responded during pandemic

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The largest marine reptile ever could match blue whales in size – Ars Technica

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Blue whales have been considered the largest creatures to ever live on Earth. With a maximum length of nearly 30 meters and weighing nearly 200 tons, they are the all-time undisputed heavyweight champions of the animal kingdom.

Now, digging on a beach in Somerset, UK, a team of British paleontologists found the remains of an ichthyosaur, a marine reptile that could give the whales some competition. “It is quite remarkable to think that gigantic, blue-whale-sized ichthyosaurs were swimming in the oceans around what was the UK during the Triassic Period,” said Dean Lomax, a paleontologist at the University of Manchester who led the study.

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Giant jawbones

Ichthyosaurs were found in the seas through much of the Mesozoic era, appearing as early as 250 million years ago. They had four limbs that looked like paddles, vertical tail fins that extended downward in most species, and generally looked like large, reptilian dolphins with elongated narrow jaws lined with teeth. And some of them were really huge. The largest ichthyosaur skeleton so far was found in British Columbia, Canada, measured 21 meters, and belonged to a particularly massive ichthyosaur called Shonisaurus sikanniensis. But it seems they could get even larger than that.

What Lomax’s team found in Somerset was a surangular, a long, curved bone that all reptiles have at the top of the lower jaw, behind the teeth. The bone measured 2.3 meters—compared to the surangular found in the Shonisaurus sikanniensis skeleton, it was 25 percent larger. Using simple scaling and assuming the same body proportions, Lomax’s team estimated the size of this newly found ichthyosaur at somewhere between 22 and 26 meters, which would make it the largest marine reptile ever. But there was one more thing.

Examining the surangular, the team did not find signs of the external fundamental system (EFS), which is a band of tissue present in the outermost cortex of the bone. Its formation marks a slowdown in bone growth, indicating skeletal maturity. In other words, the giant ichthyosaur was most likely young and still growing when it died.

Correcting the past

In 1846, five large bones were found at the Aust Cliff near Bristol in southwestern England. Dug out from the upper Triassic rock formation, they were dubbed “dinosaurian limb bone shafts” and were exhibited in the Bristol Museum, where one of them was destroyed by bombing during World War II.

But in 2005, Peter M. Galton, a British paleontologist then working at the University of Bridgeport, noticed something strange in one of the remaining Aust Cliff bones. He described it as an “unusual foramen” and suggested it was a nutrient passage. Later studies generally kept attributing those bones to dinosaurs but pointed out things like an unusual microstructure that was difficult to explain.

According to Lomax, all this confusion was because the Aust Cliff bones did not belong to dinosaurs and were not parts of limbs. He pointed out that the nutrient foramen morphology, shape, and microstructure matched with the ichthyosaur’s bone found in Somerset. The difference was that the EFS—the mark of mature bones—was present on the Aust Cliff bones. If Lomax is correct and they really were parts of ichthyosaurs’ surangular, they belonged to a grown individual.

And using the same scaling technique applied to the Somerset surangular, Lomax estimated this grown individual to be over 30 meters long—slightly larger than the biggest confirmed blue whale.

Looming extinction

“Late Triassic ichthyosaurs likely reached the known biological limits of vertebrates in terms of size. So much about these giants is still shrouded by mystery, but one fossil at a time, we will be able to unravel their secrets,” said Marcello Perillo, a member of the Lomax team responsible for examining the internal structure of the bones.

This mystery beast didn’t last long, though. The surangular bone found in Somerset was buried just beneath a layer full of seismite and tsunamite rocks that indicate the onset of the end-Triassic mass extinction event, one of the five mass extinctions in Earth’s history. The Ichthyotian severnensis, as Lomax and his team named the species, probably managed to reach an unbelievable size but was wiped out soon after.

The end-Triassic mass extinction was not the end of all ichthyosaurs, though. They survived but never reached similar sizes again. They faced competition from plesiosaurs and sharks that were more agile and swam much faster, and they likely competed for the same habitats and food sources. The last known ichthyosaurs went extinct roughly 90 million years ago.

PLOS ONE, 2024.  DOI: 10.1371/journal.pone.0300289

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