Month: October 2023

Early next month, SpaceX will send a clutch of science experiments to the space station investigating a range of topics, from high-speed laser communications to rolling atmospheric waves on Earth.

A SpaceX Falcon 9 rocket, carrying the uncrewed Dragon spacecraft, is scheduled to launch toward the International Space Station (ISS) no earlier than Nov. 5, kicking off the CRS-29 cargo mission. Launch coverage will be available here at Space.com, via NASA Television.

“All of the science really supports the initiatives of NASA, as well as the ISS program, in supporting innovative research, being able to improve science capabilities on the International Space Station, and for future commercial and exploration programs,” said Meghan Everett, deputy program scientist for the ISS program at NASA’s Johnson Space Center in Houston, during a telephone press conference on Thursday (Oct. 26).

An example is the laser experiment, called ILLUMA-T (“Integrated LCRD Low-Earth-Orbit User Modem and Amplifier Terminal”), which aims to boost ISS communications while assisting future missions in deep space. ILLUMA-T is the remaining hardware item needed to transmit data through the agency’s Laser Communications Relay Demonstration (LCRD) satellite that launched in 2021. When the system is ready, the satellite will relay the information to optical ground stations in Hawaii and California. 

Related: SpaceX to launch final piece of NASA’s 1st two-way laser communications relay  

“Future missions have potentially exceptionally large data needs, and so we have to think about how we’re going to meet those needs,” NASA’s Jason Mitchell said during the same press conference. “We all understand that more data means more discoveries,” added Mitchell, the director for the advanced communications and navigation technologies division at NASA’s space communication and navigation program. (That program is funding ILLUMA-T.)

NASA is looking to beef up its communications capabilities beyond those provided by the radio spectrum, which the agency has mostly been using for missions in the past 65 years. While the experiment is not the first laser demonstration in space, it will be the first two-way laser communications relay, agency officials have stated.

The system will use infrared light to transmit videos and images faster. NASA is counting on this technology to help amp up science returns over long distances, particularly at the moon and Mars, where the agency has plans for new human and robotic missions. 

“One of our big goals in this demonstration is to demonstrate the pointing of that laser system … from the ISS, as it’s traveling in its orbit,” Glenn Jackson, acting project manager for ILLUMA-T at NASA’s Goddard Space Flight Center near Baltimore, said in the phone call.

Given that the ISS is traveling around our planet at roughly 18,000 mph (29,000 kph), that’s no small feat. Even small Earth lasers encounter pointing issues, which may be exacerbated in space, Jackson said. An example he cited: “If you have a laser pointer and you’re trying to point that laser to a whiteboard or to your chalkboard in your classroom, sometimes you see that laser bouncing around a bit.”

The ILLUMA-T system is smaller and less massive than radio gear, which allows more room for other science payloads or fuel on future missions. Less power use also provides more resources for science instruments drawing on the spacecraft’s battery.

Other benefits include fewer issues in getting the required spectrum for launch – unlike radio, the optical spectrum is not as highly regulated, and getting a license is easier, Mitchell pointed out. 

The hope is to reduce the risk and to bring laser communications to users across the solar system as the technology matures. For example, NASA’s Artemis 2 crew that will circle the moon in 2024 plans to debut its own optical communications system “to understand what operational needs are for that [lasers] from a lunar perspective,” Mitchell said.

Numerous partners are involved in the experiment. It is managed by NASA Goddard in partnership with two entities: NASA Johnson and the Massachusetts Institute of Technology (MIT) Lincoln Laboratory in Lexington, Massachusetts. 

Select other experiments going up on CRS-29 include (in NASA’s words):

• NASA’s Atmospheric Waves Experiment (AWE). It uses an infrared imaging instrument to measure the characteristics, distribution, and movement of atmospheric gravity waves. These waves roll through Earth’s atmosphere when air is disturbed, and play a role in defining the climate. 
• Aquamembrane-3, an investigation from the European Space Agency (ESA). It continues evaluation of replacing the multi-filtration beds used for water recovery on the space station with a type of membrane known as an Aquaporin Inside Membrane.
• Gaucho Lung, sponsored by the ISS National Lab. It studies how mucus lining the respiratory system affects delivery of drugs carried in a small amount of injected liquid, known as a liquid plug. 
• Rodent Research-20. “That study is designed to look at reproductive health in female mice,” Everett said in the press conference. “We will look at the function of the ovaries during flight, and after flight … that will give us indication of the effects of microgravity on reproductive function. (It will) hopefully improve some of our knowledge of reproductive health here on the ground.” The research uses hardware developed by NASA’s Ames Research Center to safely house the animals. 

Hundreds of Roman Empire forts popped up in old spy satellite imagery depicting regions of Syria, Iraq and nearby “fertile crescent” territories of the eastern Mediterranean.

These satellites were once used for reconnaissance in the 1960s and 1970s, but their data is now declassified. Some of their archived images are now allowing for fresh archaeology finds in Earth zones often difficult for researchers to visit.

The newly found 396 forts, spotted straight from space, confirm and extend an aerial survey of the region performed in 1934; this survey had recorded 116 forts on the Roman Empire’s eastern frontier. Archaeologists continue to agree with the basic conclusion of that nearly century-old study, which is that Rome was fortifying its frontier — and the new study brings fresh perspective.

Related: Space archaeology is a thing. And it involves lasers and spy satellites  

“These forts are similar in form to many Roman forts from elsewhere in Europe and North Africa. There are many more forts in our study than elsewhere, but this may be because they are better preserved and easier to recognize,” lead author Jesse Casana, a professor of anthropology focusing on the Middle East at New Hampshire’s Dartmouth College, told Space.com in an email interview. “However, it could also have been a real product of intensive fort construction, especially during the second and third centuries AD.”

The origins of Roman Empire forts 

Most historians say the Roman Empire began around 27 BCE. The older Republic had been in the throes of a lengthy civil war after a group of senators assassinated the dictator Julius Caesar in 44 BCE, alleging Caesar had grown too powerful. 

Eventually, the Senate backed one of the rivals for Rome’s leadership — Octavian, Caesar’s heir — and gave the young man temporary dictatorship powers, as well as military backing. Very simply put, this resulted in Octavian overcoming his rivals. In 27 BCE, he received one-man leadership powers permanently from the Senate. Now called Augustus (“the exalted one”), his stated aim was to “restore the Republic” while consolidating his powers for himself and his successors.

The line of “imperators” (emperors) continued after Augustus for centuries. But during the period when the study’s newly found Roman forts were constructed – roughly spanning the second and sixth centuries CE, though other times are likely included – various difficulties were arising. Particularly in the third and fourth centuries, for example, there was no established line of emperor succession, leading to repeated assassinations and coups. 

The huge Roman Empire, stretching at its largest from Britain to Egypt, was also struggling to maintain its borders, in part due to sheer size and in part due to incursions from nomadic groups grappling with climate change. Following a few reorganizations, the Roman Empire was officially divided between two heirs in 395 CE, after the death of Emperor Theodosius I. The western side was gradually taken over by other peoples, while the eastern side persisted in what we now call the Byzantine Empire down to roughly the 1400s CE.

That brings in how the newly found forts’ functioned at the empire’s edge. 

In a 1934 study based on flights performed in the 1920s, pioneering French archaeologist Antoine Poidebard found 116 forts in an aerial survey, the study authors stated. He suggested the fortifications were supposed to be a defensive line against Persians (more properly, the Parthians and the Sasanians, who were other superpowers of the era). But a limitation of his work is that he mainly flew his plane where he believed forts would be found. The forts, to be fair, were surveyed before the existence of modern-day archaeological standards. 

Casana and fellow researchers’ new satellite image study was, on the other hand, able to cover more ground and counteracted Poidebard study’s bias. It showed the freshly discovered 396 forts had no discernible defensive north-south pattern against eastern peoples, and were instead scattered.

Related: A comet explosion may have started agriculture in Syria 12,800 years ago

The new results may confirm the suspicions of some earlier scholars, who argued the 116 Poidebard forts were too far apart to form a connective line of defenses. Instead, the encampments in modern-day Syria and Iraq were possibly used to protect caravans bringing valuable goods to and from Rome’s provinces, while allowing for communications and intercultural exchanges. 

The story of the satellites

The study images came via two satellite programs originally used for surveillance during the Cold War between the United States and the Soviet Union (and their respective allies). The nations pursued military technologies (including early space missions) on “political, economic, and propaganda fronts” with minimal use of weapons, according to Encyclopedia Britannica. 

During this time, the “Space Race” was also in full-force,  seeing both space powers rapidly accrue milestones with human and robotic space missions, such as launching the first people and sending spacecraft around the solar system. (The rivalry sometimes coalesced into moments of collaboration, however, such as the Apollo-Soyuz Test Project space mission that launched astronauts and cosmonauts together in 1975.)

One of the aims of the Cold War was rapid military reconnaissance using satellites that could promptly return photographic images to Earth. The Central Intelligence Agency’s Corona program, with assistance from the U.S. Air Force, imaged areas in nations such as China and the Soviet Union between 1959 and 1972. A successor program called Hexagon (also called Big Bird, KH-9 or KeyHole-9) continued surveying Soviet military zones between 1971 and 1986, led by the National Reconnaissance Office.

But most importantly for the new study, these satellites were specifically built to take clear and precise images.

“Because these images preserve a high-resolution, stereo perspective on a landscape that has been severely impacted by modern-day land-use changes, including urban expansion, agricultural intensification and reservoir construction, they constitute a unique resource for archaeological research,” the study authors stated in their work, published Thursday (Oct. 25) in Antiquity.

And it was actually the images’ declassification that offers such rich data harvesting grounds for archaeologists, Casana told Space.com, as the pictures are easy to source and relatively inexpensive. 

“All the satellite images we used in this study are publicly available through the U.S. Geological Survey, who serve them on their EarthExplorer data distribution portal,” he explained. “Images that are already scanned can be downloaded there for free, while unscanned images can be purchased for $30 USD.”

After downloading the images, however, came hours of processing to georeference and spatially correct the images. These processes are needed to accurately map features on the Earth’s surface using GPS technology, which itself was originally used for the military as well. Archaeologists have reshared most of their work with the community via the Corona Atlas Project led by the University of Arkansas’ Center for Advanced Spatial Technologies. The site even includes “a basic archaeological site database for the Middle East to help locate sites of interest,” Casana said.

Related: Declassified US spy satellites reveal rare look at secret Cold War space program

Aside from continuing the work of Poidebard, who was cited as influential to “a long history of scholarship” in the new study, the declassified Corona and Hexagon imagery provide other benefits to archaeologists. Ancient sites are subject to many threats, Casana pointed out. The public and media focus on the damage caused by looting and the military, but archaeologists find that “destruction of sites by urban development, agricultural intensification, and dam construction are far more widespread and severe,” he said. (Climate change has a role to play in these problems, too, as communities seek to protect food and water resources against a warming planet.)

“The real value in historical, high-resolution imagery like Corona and Hexagon is in preserving a picture of a landscape that by and large no longer exists,” Casana said, noting the spy imagery is roughly half a century old and there has been a lot of change in Iraq and Syria since then. “Our study also helps show that an unknown number of other sites were also likely lost in the time between Poidebard’s flights in the 1920s and the Corona imagery of the late 1960s,” he added.

More broadly, the study may also add nuance to how the Romans managed their empire frontiers. Ancient Romans were famously militaristic and well-known for incursions reaching areas as far as Britain; they sometimes even fought with or allied with local tribes depending on the local commander’s (or emperor’s) purpose. At the same time, however, the Romans depended on trade and valued it. The researchers say their new fort study may help provide more fodder for the Roman empire’s interregional links.

But the new study might be subject to preservation bias, the authors warn. The density of forts seen in some areas – as well as the distribution of those forts that remain visible after all the eons – may reflect the reality that many others were lost due to “settlement and land-use practices,” the authors stated. And the ground continues to change rapidly; many forts Poidebard spotted were no longer visible just a generation later, in the spy satellite images. 

That said, the archaeologists have found an additional 106 “fort-like features” in a subregion of the satellite study, in which future discoveries may lurk. “We are planning to expand the survey to prospect for more sites, including forts and others,” Casana said. “We will work within our current survey area using additional forms of imagery, such as the more recently declassified Hexagon and U2 spy plane imagery, as well as expanding regionally into other parts of the Middle East.”

This podcast originally aired on August 17, 2021.

Karen Hopkin: This is Scientific American’s Science, Quickly. I’m Karen Hopkin.

What has one head, one foot and one heck of an origin story? No, it’s not a strange new superhero. It’s a microscopic worm called a rotifer that was brought back to life after spending about 25,000 years locked in the arctic permafrost. Its tale is told in the journal Current Biology. [Shmakova et al., A living bdelloid rotifer from 24,000-year-old Arctic permafrost.]

Stas Malavin: So this is a long term topic for this lab.

Hopkin: Stas Malavin of the Institute of Physicochemical and Biological Problems in Social Science in Pushchino, Russia. He and his colleagues have spent decades probing the Siberian permafrost. And they’ve managed to revive a variety of interesting organisms, from a plant seed and simple bacteria to scores of more sophisticated single-celled critters.

Malavin: We have isolated around 30 or 40 strains already of unicellular eukaryotes.

Hopkin: But for some reason, people weren’t totally wowed by resurrected amoebas.

Malavin: Yeah, they don’t respect them, definitely. Rotifer is much, much better.

Hopkin: Rotifers are better—or at least more interesting—because they’re multicellular animals, with a head and a body, that can eat, crawl around and make more rotifers. And considering they’re more or less teeny tiny worms, they’re actually cute little guys.

Malavin: No, they don’t have guys. They are all females [laughs].

Hopkin: In fact, these little ladies reproduce asexually, laying eggs that hatch into the next generation of self-propagating rotifers. So they’re easy to grow in the lab, although not as easy to gather in the lowlands of Siberia.

Malavin: So this place is relatively distant. First, we go by two or three planes. Then we go by boat or by helicopter to those places.

Hopkin: Then they drill.

Malavin: One or two or more boreholes. In older times, people used the first borehole as fridge to store consequent cores in there.

Hopkin: Nowadays portable freezers help them keep their samples chilled until they get to the lab. There, Malavin and his team cut a small piece from the center of the core to prevent potential contamination with modern microbes. Then they pop it in a nice warm petri dish.

Malavin: This is called an enrichment cultivation in microbiology. Because those organisms are attached to particles, they are contorted, folded up, and we cannot see them even with microscope. So we need to wait until they reactivate from this cryptobiosis, come out from this permafrost piece, start moving, multiplying, and so on.

Hopkin: Not every sample yields success.

Malavin: Usually we see nothing. It’s relatively rare event when something alive is isolated from this cores—which is also considered an indirect proof that it’s not a contamination. Because, you know, if it was like every sample, or maybe each second sample, will yield some live organism. Here it’s about one out of 20 or even more rare.

Hopkin: And in one sample collected in 2015, the researchers found this one little rotifer. They allowed it to reproduce and conducted some DNA analyses, which showed that although their frozen rotifer is similar to modern varieties, it’s not exactly the same.

Malavin: So we consider it a new species to science.

Hopkin: And based on radiocarbon dating of other organic materials in the permafrost sample, they consider it to be between 20,000 and 30,000 years old.

Malavin: That’s approximate. But anyway, it’s two orders of magnitude or maybe three orders of magnitude more than was known for cryptobiosis in those animals.

Hopkin: So, the previous record for frozen rotifers was a decade or so. And this guy—I mean, gal—was around when woolly mammoths walked the planet.

Now, the fact that rotifers can spring to life after a thaw is not a total surprise. Entering a state of cryptobiosis allows even modern rotifers to survive seasonal changes in their local environment and more otherworldly assaults.

Malavin: They were actually sent into space, into open space, and they survived, and so on.

Hopkin: The next step is studying how rotifers can chill for millennia and still maintain their cellular integrity.

Malavin: The main mechanism, actually, is the suspension of animation, the suspension of metabolism up to almost zero or maybe zero state. So they don’t need energy, almost don’t need energy.

Hopkin: They also produce special proteins that act as antifreeze or control the formation of ice crystals: findings that could enhance the preservation of human tissues and organs.

Malavin: That’s why we are going to study proteins that help rotifers to survive in those conditions.

Hopkin: And when they figure it out …

Malavin: Maybe we cry, “Yeaaaah! We did it!” Ha. Or something like that.

Hopkin: For Scientific American’s Science, Quickly this is Karen Hopkin.

[The above text is a transcript of this podcast.]