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NASA likely to redo hot-fire test of its Space Launch System core stage

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Enlarge / At 4:27pm central time on Saturday, the SLS rocket core stage ignited its four RS-25 engines at NASA’s Stennis Space Center. The test was to last up to eight minutes.

Trevor Mahlmann for Ars

Following the unsuccessful completion of a Space Launch System hot fire test, NASA is likely to conduct a second “Green Run” firing in February.

On Tuesday, three days after the first hot-fire test attempt, NASA released a summary of its preliminary analysis of data from the 67.2-second test firing. The report highlights three issues, none of which appears to be overly serious but will require further investigation.

The agency found that the test, conducted at the Stennis Space Center in Mississippi, was automatically shut down by an out-of-limits reading of hydraulic pressure in the thrust vector control mechanism used to gimbal, or steer, the engines. At 64 seconds into the test, the rocket began a pre-programmed sequence to gimbal its engines as if it were in flight. Shortly after, the pump-return pressure fell below the redline of 50 pounds per square in gauge, to 49.6. This pressure limit, the agency said, was more stringent than an actual flight redline and was set to protect against potential damage on the test stand.

Another issue, the “major component failure” in Engine 4, actually appears to be a relatively minor problem in which a redundant sensor failed. This is good, because it means that NASA would likely not have to swap out this engine from the core stage. There are four space shuttle main engines used on the SLS rocket.

Finally, the “flash” observed in the engine section seems to be fairly normal. A visual inspection of the thermal blankets between engines shows some scorching, but this is expected. There were no indications of a fire, leak, or other issue.

To repeat or not repeat?

The published NASA summary does not discuss whether the agency will press ahead with a second test of the core stage. Prior to the test, NASA had hoped to run the engines for at least 250 seconds to obtain a full suite of data about the core stage performance. Obviously, they only ran the engines for about one-quarter of that time.

According to sources at the agency, program managers are in fact leaning toward conducting a second hot-fire test in Mississippi. Due to the need to obtain more propellant at the test site, conduct minor refurbishment to the vehicle, and possibly change the erratic sensor on Engine 4, the agency estimates it will require about three to four weeks before conducting another test.

NASA and the core stage’s primary contractor, Boeing, did collect a lot of data about the test. The agency said that, of its 23 test objectives, 15 were completed with 100 percent of the data sought. Four others got most of the data sought, while three had partial data, and one no data. (This was a test of how the liquid oxygen tank pressure would respond when liquid oxygen was largely used up and the tank emptied.)

NASA engineers are now studying the data in greater detail and will soon perform a risk assessment to determine the hazards of skipping a second test. As it is standard practice to re-test in such circumstances, it is highly likely a second test will occur.

It remains difficult to quantify what this means to the schedule for launching this core stage as part of the Artemis I mission. Before this delay, NASA was already going to struggle to make its goal of launching an uncrewed Orion spacecraft around the Moon before the end of 2021. There was not much margin left in the schedule, and a launch this year assumed smooth operations in stacking and integration—a big assumption. Now it appears likely that NASA will lose at least a month.

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China’s carbon pollution now surpasses all developed countries combined

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Carbon pollution from China’s bustling, coal-intensive economy last year outstripped the carbon pollution of the US, the EU, and other developed nations combined, making up a whopping 27 percent of all greenhouse gas emissions worldwide.

As China’s economy has grown in the last 30 years, so too have its emissions. While pollution from developed countries has largely been flat since 1990, it has more than tripled in China. The country’s soaring emissions and stable population mean that its per capita emissions have grown quickly, too. At 10.1 tons per person, emissions are just below the 10.5 ton average of the 37-nation Organization for Economic Cooperation and Development, or OECD.

The US still leads the world in per capita emissions, at 17.6 tons per person, according to Rhodium Group’s numbers, though President Joe Biden has pledged that the US will halve emissions by 2030. The other developed countries in the report include all 27 current EU member states: the UK, Australia, Canada, Chile, Iceland, Israel, Japan, Korea, Mexico, New Zealand, Norway, Switzerland, and Turkey.

China’s draconian lockdowns early in the COVID-19 pandemic allowed the country’s economy to bounce back relatively quickly, and as a result, Rhodium expects that China’s emissions per capita in 2020 will surpass the average of the OECD nations.

Over the last few years, China’s growing carbon emissions have drawn the attention of leaders from around the world. In 2018, the Communist Party lifted a ban on the construction of new coal plants, and its policies have become more generous in years since. Though China has installed a large number of solar panels and wind turbines, fossil fuels still power the vast majority of its industries and transportation modes. Its electrical grid is particularly carbon-intensive—half of the world’s coal is burned inside China’s borders.

China counters that it’s within its rights to burn such vast quantities of fossil fuels since developed countries did the same over the past few centuries. The country is not entirely wrong: developed economies have produced the most cumulative emissions since 1750, around 1,000 gigatons. But China’s rise means it has swiftly become the largest contributor in recent years. The country emitted 52 megatons of carbon dioxide and equivalent greenhouse gases in 2019, according to a report by the Rhodium Group, and has emitted a cumulative 200 gigatons since 1750.

China’s argument has merit, but it also elides the fact that renewable sources like wind and solar were not available on the same scale as fossil fuels for much of the last 300 years. Half the OECD’s cumulative carbon emissions were produced before 1980, when wind and solar were expensive compared with fossil fuels. Today, though, those numbers have largely flipped. In the US, it’s now more expensive to run 80 percent of the nation’s coal power plants than it would be to shut them down and install new wind farms and solar plants.

Wind and solar prices are dropping in China, too. They’re expected to undercut new coal plants this year, according to consultancy Wood Mackenzie, which could make the 247 GW of coal power the country has under development look not just archaic but unnecessarily expensive. It could imperil China’s investments elsewhere. The country is the world’s largest financier and developer of coal plants abroad, with over 100 GW funded by Chinese companies.

China’s pledge for the Paris Agreement states that it will hit its carbon pollution peak in 2030 and reach net zero 30 years later. Those targets appear achievable, according to the Climate Action Tracker, an independent analyst, but the group says the goals are “highly insufficient” to reach the 2˚ C warming target set forth in the agreement.

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Researchers peek at proprietary data of US particle physics lab Fermilab

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Multiple unsecured entry points allowed researchers to access data belonging to Fermilab, a national particle physics and accelerator lab supported by the Department of Energy.

This week, security researchers Robert Willis, John Jackson, and Jackson Henry of the Sakura Samurai ethical hacking group have shared details on how they were able to get their hands on sensitive systems and data hosted at Fermilab.

After enumerating and peeking inside the fnal.gov subdomains using commonly available tools like amass, dirsearch, and nmap, the researchers discovered open directories, open ports, and unsecured services that attackers could have used to extract proprietary data.

A naked FTP server

Among the exposed assets was Fermilab’s FTP server, ftp.fnal.gov, containing heaps of data that allowed “anonymous” login without a password.
Enlarge / Among the exposed assets was Fermilab’s FTP server, ftp.fnal.gov, containing heaps of data that allowed “anonymous” login without a password.

Sakura Samurai

The server exposed configuration data for one of the Fermilab’s experiments called “NoVa,” which concerns studying the purpose of neutrinos in the evolution of cosmos.

The researchers discovered that one of the tar.gz archives hosted on the FTP server contained Apache Tomcat server credentials in plaintext:

Sakura Samurai

The researchers verified that the credentials were valid at the time of their discovery but ceased experimenting further so as to keep their research efforts ethical.

Thousands of documents and project tickets exposed

Likewise, in another set of unrestricted subdomains, the researchers found over 4,500 tickets used for tracking Fermilab’s internal projects. Many of these contained sensitive attachments and private communications.

Sakura Samurai

And yet another server ran a web application that listed the full names of users registered under different workgroups, along with their email addresses, user IDs, and other department-specific information.

A fourth server identified by the researchers exposed 5,795 documents and 53,685 file entries without requiring any authentication.

“I was surprised that a government entity, which has over a half a billion-dollar budget, could have so many security holes,” Willis, the Sakura Samurai researcher, told Ars in an interview. “I don’t believe they have even basic computer security after this engagement, which is enough to keep you up at night. I wouldn’t want a malicious actor to steal important data, which has cost the US hundreds of millions to produce, while also leaving the potential to manipulate equipment that could have a severe impact.”

Serious flaws resolved swiftly

The research activities performed by Willis, Jackson, and Henry were consistent with Ferminab’s vulnerability disclosure policy. Fermilab was quick to respond to the researchers’ initial report and squashed the bugs swiftly.

“Fermilab managed the interactions regarding the findings in a quick and positive way. They didn’t question the authenticity of our vulnerabilities and immediately dug in and patched—acknowledging the sense of urgency,” Jackson said. “The first thought that we had was about the possibility of a nation-state threat actor acquiring this data, especially because it’s no surprise that Fermilab works on groundbreaking scientific research.”

“We knew we had to act quickly and inform Fermilab. Nonetheless, still crazy to see the ease in which we acquired sensitive data, which included credentials to scientific equipment and servers,” he added.

This discovery of a US government-funded national lab having serious security flaws that are trivial to exploit comes as multiple US federal agencies continue to be targets of cyberattacks.

Just last week, Ars reported that threat actors had potentially hacked at least five US government agencies via Pulse Connect Secure VPN vulnerabilities. Separately, the FBI is investigating an extortion attempt by ransomware operators against the Metropolitan Police Department in Washington, DC.

Fermilab declined to comment.

The researchers’ detailed findings related to the research are provided in their blog post.

Ax Sharma is a security researcher, engineer, and reporter who publishes in leading publications. His expertise lies in malware research, reverse engineering, and application security. He’s an active community member of the OWASP Foundation and the British Association of Journalists.

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Earliest known burial in Africa is that of a small, fragile child

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Mohammad Javad Shoaee

78,000 years ago, a child died two to three years into their life in the coastal highlands of what is now Kenya. Archaeological evidence suggests that survivors wrapped the small body tightly before laying it, curled on one side with the tiny head resting on a pillow, in a carefully dug pit in Panga ya Saidi cave. The child’s grave is now the oldest known example of people in Middle Stone Age Africa burying their dead.

A child called Mtoto

A thesaurus is a handy thing, but sometimes seemingly tiny differences in meaning can actually have a huge impact. Consider the implications of “disposing of bodies” versus “laying the dead to rest.” One of the things archaeologists are most interested in about the lives of the earliest members of our species—and our close relatives, now extinct—is when and how we first began to make that distinction.

When did early humans stop viewing a dead human body as something smelly to be removed from the living area before it attracted scavengers and sickness? When did they decide it needed to be treated carefully to ensure safe passage to an afterlife—or perhaps give peace for the living?

Short of time travel, the best way archaeologists can figure out when people started believing in concepts like a spirit or an afterlife is to figure out when people started burying their dead with, as paleoanthropologist Louise Humphrey of the National History Museum of London puts it, “an investment of time and resources beyond what is strictly required to dispose or make use of the corpse.” That could mean placing the body carefully in a particular position, wrapping it in a shroud or supporting it with pillows, or even burying objects in the grave.

Mtoto is what archaeologists named the 78,000-year-old toddler’s skeleton recently unearthed at Panga ya Saidi Cave in Kenya (Mtoto is a Swahili word for child). And Mtoto clearly received that kind of tender attention from their community.

The remains were located by paleoanthropologist Maria Martinon-Torres, of Spain’s National Research Center on Human Evolution, and her colleagues. They found the small grave pit dug into several older layers of sediment in the cave, with the pit filled in with a mix of sediment scooped up from the cave floor. Inside, a few “fragile and degraded” pieces of bone were all that remained: the base of the skull and part of the lower jaw, part of the spine and ribs, and some fragments of arm and leg bones. The remains were so fragile that archaeologists had to wrap the whole burial pit in plaster and bring the plaster-wrapped chunk of sediment back to a lab at the Museum of Kenya to excavate under better conditions.

Mtoto lay on the right side, with the legs curled up to the chest. The child’s right collarbone and upper ribs had been turned and pressed inward, exactly the way archaeologists would expect if someone had wrapped the child’s upper body tightly, perhaps with a cloth or hide, before burial. Sometime after burial, the head and neck had collapsed downward, as if a support—maybe a cushion or a wooden block—had decayed away underneath it. And a few large shells mixed in with the grave soil may (or may not) have been funeral offerings.

When Martinon-Torres and her colleagues examined a few of Mtoto’s teeth—a mixture of deciduous, or baby, teeth and adult molars that hadn’t emerged from the jaw yet—they saw that the child was clearly a member of our species, Homo sapiens. And optically stimulated luminescence, a dating technique that measures when rock or sediment last saw sunlight, placed the grave soil at around 78,000 years old. That makes Mtoto the oldest human with a formal, deliberate grave in Africa.

Life and death in the Middle Stone Age

What does that actually tell us about the lives and beliefs of ancient people or the gradual emergence of the first human cultures? The Middle Stone Age was a period when what archaeologists think of as “modern human behavior” started taking the world by storm. It had been going on for about 200,000 years when Mtoto died, and it lasted for at least another 50,000 years. Modern human behavior, in this case, includes things like using symbols, creating art, and making jewelry, and people at several places in Africa were definitely doing those things long before Mtoto’s people grieved their loss.

In Europe and the Levant, archaeologists have found evidence that people—both Homo sapiens and Neanderthals—buried their dead in or near their living spaces as early as 120,000 years ago. That’s also what seems to have happened with Mtoto at Panga ya Saidi.

“Burial in residential localities, such as at Panga ya Saidi, has been suggested to reflect mourning behavior and the intention to keep the dead nearby,” wrote Martinon-Torres and her colleagues. Of course, that’s an informed guess; archaeologists can’t really know what ancient people were thinking. But it fits what we know about similar choices in several modern cultures.

But all of that—burials dating to 120,000 years ago in the Levant, combined with evidence of symbolic thinking and art much earlier than that in Africa—makes it seem a little surprising that the earliest actual burial in Africa is just 78,000 years old. After all, burial seems like such a key piece of evidence about ancient spiritual beliefs, and people clearly had laid the cultural groundwork for those beliefs long before Mtoto’s time.

The key may be that “laying the dead to rest” doesn’t always mean “digging a hole and filling it up with dirt afterward.” A quick look at modern cultures around the world reveals lots of different ideas about the proper way to lay the dead to rest, and each culture has its own reasons for what it does. Many of those funeral practices wouldn’t be likely to leave archaeological traces tens of thousands of years in the future.

Burial just happens to be one of the practices that’s most likely to leave remains mostly intact for archaeologists to find, and it’s also relatively easy to recognize a deliberate burial. But in tropical settings like coastal Kenya, buried bones don’t always last millennia; even what was left of Mtoto’s skeleton was in a “fragile and degraded” state, after all. It’s reasonably likely that for every burial like Mtoto’s, there are others that have long since vanished without a trace—lives, deaths, and afterlives forever beyond knowing.

“The absence of a behavior does not necessarily imply that the capacity for such behavior was lacking,” wrote Martinon-Torres and her colleagues.

There’s more than one way to hide a body

People in Africa evidently laid their dead to rest very deliberately, although in other ways, perhaps for hundreds of thousands of years before Mtoto’s burial—and possibly before Homo sapiens had technically come into being. Paleoanthropologists Lee Berger and John Hawks contend that Homo naledi carried their dead through the narrow tunnels into the darkness of Rising Star Cave in South Africa around 300,000 years ago. Archaeologists are still debating that claim, but if Berger and Hawks are correct, Rising Star is an example of a funerary cache—a place where people put their dead without necessarily digging a hole to bury them in. Sima de los Huesos cave in Spain may have served a similar purpose for other hominins there around 400,000 years ago.

The other two earliest human “burials” in Africa are a 68,000-year-old grave in Taramsa, Egypt, and a 58-to 74,000-year-old one at Border Cave, South Africa. But they’re also technically funerary caches rather than burials, according to the researchers. Regardless of the technicalities, at both sites, people clearly took time and effort to lay the remains to rest with care; the infant at Border Cave was even interred with a perforated shell, painted with ocher.

And that’s the really unsettling thing all three of Africa’s oldest human graves have in common: they all belong to young children. It suggests, wrote Martinon-Torres and her colleagues, that “Homo sapiens populations were intentionally preserving the corpses of young members of their groups between about 78,000 and 69,000 years ago.” In fact, if we look at every known Homo sapiens or Neanderthal burial from 120,000 years ago to the end of the Pleistocene, slightly more than half belong to children.

Children’s bones are smaller, more fragile, and less likely to survive millennia in the ground or the recesses of a cave than those of adults. That may tell us something about ancient demographics; it could point to a higher percentage of children in the population, a higher child mortality rate, or likely a combination of both.

Nature, 2021 DOI: 10.1038/s41586-021-03457-8  (About DOIs).

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