Perseverance Collects Its First Martian Rock Sample

The rock core has been sealed in an airtight titanium sample container and will be accessible in the future. 

The first piece of Martian rock, a core from Jezero Crater little thicker than a pencil, was collected today by NASA's Perseverance rover. 

The historic milestone was verified by data obtained by mission controllers at NASA's Jet Propulsion Laboratory (JPL) in Southern California. 

The core has been sealed in an airtight titanium sample container and will be retrievable in the future. 

NASA and ESA (European Space Agency) are preparing a series of future flights to return the rover's sample tubes back Earth for further analysis as part of the Mars Sample Return program. 

These samples would be the first time materials from another planet have been scientifically identified , chosen and returned to our world. 

NASA Administrator Bill Nelson stated, "NASA has a history of establishing high objectives and then achieving them, demonstrating our nation's dedication to exploration and innovation." 

“This is a huge accomplishment, and I can't wait to see what Perseverance and our team come up with next.” 

Perseverance's mission includes studying the Jezero region to understand the geology and ancient habitability of the area, as well as characterizing the past climate, in addition to identifying and collecting samples of rock and regolith (broken rock and dust) while searching for signs of ancient microscopic life. 

“This is really a momentous moment for all of NASA research,” said Thomas Zurbuchen, assistant administrator for science at NASA Headquarters in Washington. 

“We will be doing the same with the samples Perseverance gathers as part of our Mars Sample Return program, much as the Apollo Moon missions showed the lasting scientific significance of returning samples from other planets for examination here on our planet. 

We anticipate jaw-dropping findings across a wide range of scientific disciplines, including investigation into the issue of whether life ever existed on Mars, using the most advanced science equipment on Earth.”

Perseverance Rover Sample Tubes from NASA. 

The rover's sample tubes, marvels of engineering, must be robust enough to securely transport Red Planet materials back to Earth in perfect shape. 

The tubes in NASA's Mars 2020 Perseverance rover's belly are set to transport the first samples from another planet back to Earth in history. 

Future researchers will utilize these carefully chosen samples of Martian rock and regolith (broken rock and dust) to seek for evidence of possible microbial life on Mars in the past, as well as to address other important questions regarding the planet's history. 

On February 18, 2021, Perseverance will touch down at Mars' Jezero Crater. 

The 43 sample tubes heading to Mars, which are about the size and form of a typical lab test tube, must be lightweight and durable enough to withstand the rigors of the round journey, as well as clean enough that future scientists can be sure that what they're studying is 100 percent Mars. 

"When compared to Mars, Earth is brimming with signs of life," Ken Farley, a Mars 2020 project scientist at Caltech in Pasadena, said. 

"We wanted to get rid of those indications completely so that any residual evidence could be reliably identified and distinguished when the first samples were returned."

Engineered containers have been used to transport samples from other planets since Apollo 11. 

In 1969, Neil Armstrong, Michael Collins, and Buzz Aldrin brought back 47.7 pounds (21.8 kilograms) of samples from the Moon's Sea of Tranquility in two triple-sealed briefcase-size metal cases. 

The rock boxes on Apollo, on the other hand, only had to maintain their contents immaculate for approximately 10 days – from the lunar surface until splashdown – before being taken away to the Lunar Receiving Laboratory. 

The scientific value of Perseverance's sample tubes must be isolated and preserved for more than ten years. 

Sample Return from Mars

Mission scientists will decide when and where NASA's newest rover will dig for samples as it explores Jezero Crater. 

The Sample Caching System, the most complex and most sophisticated device ever launched into space, will be used to package this valuable Martian cargo. 

After the samples have been placed on the Martian surface, NASA will complete the relay by launching two more missions in collaboration with ESA (the European Space Agency). 

The sample return campaign's second mission will dispatch a "fetch" rover to collect the hermetically sealed tubes and transfer them to a dedicated sample return container within the Mars Ascent Vehicle. 

If the Mars 2020 Perseverance rover stays healthy for the duration of the mission, it may transport tubes containing samples to the area of the Mars Ascent Vehicle. 

The tubes will subsequently be sent into orbit by the Mars Ascent Vehicle. 

The last mission will send an orbiter to Mars to meet the enclosed samples, collect them in a highly secure containment capsule, and return them to Earth (as early as 2031). 

Sturdy Containers

Each sample tube is made mostly of titanium and weighs less than 2 ounces (57 grams). 

After Perseverance places the tubes on Mars' surface, a white outer covering protects them from being heated by the Sun, which may change the chemical makeup of the samples. 

The crew will be able to identify the tubes and their contents thanks to laser-etched serial numbers on the outside. 

Each tube must fit within Perseverance's Sample Caching System's stringent constraints, as well as those of future missions. 

"We discovered almost 60 distinct measurements to examine despite the fact that they are less than 6 inches [15.2 cm] long," stated JPL Sample Tube Cognizant Engineer Pavlina Karafillis. 

"Because of the complexities of all the intricate processes they would travel through throughout the Mars Sample Return mission, the tube was considered unsuitable for flight if any measurement was off by approximately the thickness of a human hair." #Jezero is 100 percent pure.# Precision engineering is just one aspect of the task at hand. 

The tubes are also the result of stringent cleaning requirements. 

All of NASA's planetary missions use stringent procedures to avoid the entry of organic, inorganic, or biological material from Earth. 

However, since these tubes may contain evidence that life previously existed elsewhere in the cosmos, the Mars 2020 team needed to further minimize the chance that they could house Earthly artifacts that would obstruct the scientific process. 

Nothing should be in a tube until the Sample Caching System starts filling it with 9 cubic inches (147 cubic centimeters) of Jezero Crater, according to the directive (about the size of a piece of chalk). 

"And they meant it when they said 'nothing,'" Ian Clark, the mission's assistant project systems engineer for sample tube cleaning at JPL, said. 

"For example, we wanted to keep the total quantity of Earth-based organic molecules in a particular sample to fewer than 150 nanograms to accomplish the type of research the project is pursuing. 

We were restricted to fewer than 15 nanograms in a sample for a group of certain chemical components - ones that are highly suggestive of life." A billionth of a gram is referred to as a nanogram. 

A typical thumbprint contains approximately 45,000 nanograms of organics, which is about 300 times the maximum permitted in a sample tube. 

The crew had to rewrite the book on cleaning in order to satisfy the mission's strict requirements. 

"All of our assembly was done in a hyper-clean-room environment, which is really a clean room within a clean room," Clark said. 

"The sample tubes would be cleaned with filtered air blasts, washed with deionized water, and acoustically cleaned with acetone, isopropyl alcohol, and other exotic cleaning chemicals in the interim between assembly processes." The crew would test impurities and bake the tubes after each cleaning for good measure. 

Each of the 43 sample tubes chosen for flight from a field of 93 had produced almost 250 pages of paperwork and 3 terabytes of pictures and movies by the time they were chosen. 

Up to 38 of the tubes onboard Perseverance will be filled with Martian rock and regolith. 

The other five are "witness tubes," which have been filled with molecular and particle contaminants-capturing materials. 

They'll be opened one at a time on Mars, mainly at sample collection sites, to observe the ambient environment and record any Earthly impurities or pollutants from the spacecraft that may be present during sample collection. 

The return and analysis of the sample and witness tubes on Earth will enable the entire range of terrestrial scientific laboratory capabilities to examine the samples, utilizing equipment that are too big and complicated to transport to Mars. 

More Information about the Mission

Astrobiology, particularly the hunt for evidence of ancient microbial life, is a major goal of Perseverance's mission on Mars. 

The rover will study the planet's geology and climatic history, lay the path for human exploration of Mars, and be the first mission to gather and store Martian rock and regolith (broken rock and dust). 

Following missions, which NASA is considering in collaboration with ESA (European Space Agency), would send spacecraft to Mars to retrieve these stored samples from the surface and return them to Earth for further study. 

The Mars 2020 mission is part of a broader program that includes lunar missions in order to prepare for human exploration of Mars. 

NASA's Artemis lunar exploration plans are tasked with sending humans to the Moon by 2024 and establishing a long-term human presence on and around the Moon by 2028. 

The Perseverance rover was constructed and is operated by JPL, which is administered for NASA by Caltech in Pasadena, California.

The Mars 2020 Perseverance mission is part of NASA's Moon to Mars exploration strategy, which includes Artemis lunar missions to assist prepare for human exploration of Mars. 

The Perseverance rover was constructed and is operated by JPL, which is administered for NASA by Caltech in Pasadena, California. 

For additional information about Perseverance, go to: 

mars.nasa.gov/mars2020/ 

nasa.gov/perseverance

Courtesy: NASA.gov

~ Jai Krishna Ponnappan

You may also want to read more about Space Missions and Systems here.

How Many Samples Will NASA' s Perseverance Rover Collect On Mars?

On August 6, NASA's Perseverance rover tried to drill into the Martian surface for the first time after six months of traveling on Mars. 

Everything seemed to proceed according to plan, but when the rover's operators examined the sample tube after it had been sealed and stowed within the rover, they discovered it to be empty. 

• Jennifer Trosper, the Perseverance project manager at NASA's Jet Propulsion Laboratory, said, "It went pretty well, other than the rock reacted in a manner that didn't enable us to collect any material in the tube." 

• The mission's operators believe that when the rover bore into the rock to collect a sample, it disintegrated into a fine powder and spilled out of the tube, based on the data. 

Trosper adds, "We need a more cooperative kind of rock." 

• “This one was crumbly — it may have had a firm surface on the outside, but as we went inside, all the grains simply fell apart.” 

• This didn't happen during Earth-based testing of the sample equipment, and it hasn't happened with any of the previous Mars rovers. 

• While the sampling tube cannot be unsealed and reused, researchers had requested a sample of Martian air, which is included in the sealed tube. 

• Trosper explains, "We weren't aiming to capture the air sample, but it's not a waste of a tube." 

There are 43 sample tubes on Perseverance, so there are still lots of chances to gather Martian rocks. 

• When it comes to future sample efforts with Perseverance, Trosper believes this failed endeavor isn't a reason for worry. 

• The crew intends to utilize the scientific equipment aboard the rover to check that a sample was obtained before sealing the tube and stashing it within the rover for the next attempt, which is scheduled for early September.

During its two-year journey, the rover will gather approximately 40 samples. 

• Perseverance will eventually store these samples on Mars' surface, where they will be picked up and returned to Earth by a later NASA mission. 

• Returning the samples to Earth will enable scientists to examine them in much more depth than we can on Mars, particularly when looking for indications of previous life.

The Mars 2020 Perseverance mission is part of NASA's Moon to Mars exploration strategy, which includes Artemis lunar missions to assist prepare for human exploration of Mars. 

The Perseverance rover was constructed and is operated by JPL, which is administered for NASA by Caltech in Pasadena, California. 

For additional information about Perseverance, go to: 

mars.nasa.gov/mars2020/ 

nasa.gov/perseverance

Courtesy: NASA.gov

~ Jai Krishna Ponnappan

You may also want to read more about Space Missions and Systems here.

How Does NASA's Perseverance Rover Take Selfies On Mars?

The historic photo of the rover next to the Mars Helicopter turned out to be one of the most difficult rover selfies ever shot. 

The procedure is explained in detail in this video, which also includes additional audio. 

Have you ever wondered how rovers on Mars snap selfies? 

NASA's Perseverance rover took the historic April 6, 2021, picture of itself alongside the Ingenuity Mars Helicopter in color video. 

The sound of the arm's motors spinning was recorded by the rover's entry, descend, and landing microphone as an added bonus. 

Engineers may use selfies to evaluate the rover's wear and tear. They do, however, inspire a new generation of space aficionados: 

• Many members of the rover crew may recall a favorite picture that first piqued their interest in NASA. 

• Vandi Verma, Perseverance's lead engineer for robotic operations at NASA's Jet Propulsion Laboratory in Southern California, stated, "I got into this when I saw a photo from Sojourner, NASA's first Mars rover." 

• Verma served as a driver for the agency's Opportunity and Curiosity rovers, and she was involved in the first selfie taken by Curiosity on Oct. 31, 2012. 

• “We had no idea when we snapped that first selfie that these would become so iconic and routine,” she added. 

• The rover's robotic arm twists and maneuvers to capture the 62 pictures that make up the image, as shown on video from one of Perseverance's navigation cameras. 

• What it doesn't show is how much effort went into creating the first selfie. Let's take a deeper look. 

Teamwork. 

Perseverance's selfie was made possible by a core group of approximately a dozen individuals, including rover drivers, JPL engineers who conducted tests, and camera operations engineers who created the camera sequence, analyzed the pictures, and stitched them together. 

It took approximately a week to plan out all of the necessary individual instructions. 

• Everyone was working on “Mars time,” which meant being up in the middle of the night and catching up on sleep throughout the day (a day on Mars is 37 minutes longer than on Earth). 

• These members of the crew would occasionally forego sleep in order to complete the selfie. JPL collaborated with Malin Space Science Systems (MSSS) in San Diego, which designed and operated the selfie camera. 

The camera, dubbed WATSON (Wide Angle Topographic Sensor for Operations and eNgineering), is intended for close-up detail pictures of rock textures rather than wide-angle images. 

• Engineers had to order the rover to snap hundreds of separate pictures to create the selfie since each WATSON image only captures a tiny part of a scene. 

• Mike Ravine, MSSS's Advanced Projects Manager, stated, "The thing that required the greatest care was putting Ingenuity into the proper position in the selfie." 

“Considering how tiny it is, I think we did fairly well.” The MSSS image processing experts got to work as soon as the pictures from Mars arrived. 

• They begin by removing any imperfections produced by dust that has collected on the light sensors of the camera. 

• They next use software to combine the individual picture frames into a mosaic and smooth out the seams. 

• Finally, an engineer warps and crops the mosaic to make it seem more like a standard camera picture that the general public is familiar with. 

Simulations on a computer. 

Perseverance, like the Curiosity rover (seen taking a selfie in this black-and-white video from March 2020), has a spinning turret at the end of its robotic arm. 

• The WATSON camera, which remains focused on the rover during selfies while being tilted to record a portion of the landscape, is housed in the turret among other scientific equipment. 
• The arm serves as a selfie stick in the final result, staying just out of frame. 

• Perseverance is considerably more difficult to get to video its selfie stick in action than Curiosity. 
• Perseverance's turret is 30 inches (75 centimeters) wide, compared to Curiosity's 22 inches (55 centimeters). 

• That's the equivalent of waving a road bike wheel a few millimeters in front of Perseverance's mast, the rover's "head." 
• JPL developed software to prevent the arm from colliding with the rover. 

• The engineering team changes the arm trajectory every time a collision is detected in simulations on Earth; the procedure is repeated hundreds of times to ensure the arm motion is safe. 
• The last instruction sequence brings the robotic arm as near to the rover's body as possible without touching it. 

Other simulations are performed to verify that the Ingenuity helicopter is properly positioned in the final photo, or that the microphone can catch sound from the robotic arm's motors, for example. 

Microphone Onboard

Perseverance has a microphone in its SuperCam instrument in addition to its entrance, descent, and landing microphones. 

• The microphones are a first for NASA's Mars mission, and audio will be a valuable new tool for rover engineers in the coming years. 

• It may be used to give crucial information about whether something is functioning properly, among other things. 

• Engineers used to have to make do with listening to a test rover on Earth. 

“It's like your car: even if you're not a technician, you may hear an issue before you know there's a problem,” Verma said. 

The humming engines sound strangely melodic when echoing through the rover's chassis, despite the fact that they haven't heard anything alarming thus yet. 

More Information about the Mission. 

• Astrobiology, particularly the hunt for evidence of ancient microbial life, is a major goal for Perseverance's mission on Mars. 

• The rover will study the planet's geology and climatic history, lay the path for human exploration of Mars, and be the first mission to gather and store Martian rock and regolith (broken rock and dust). 

• Following NASA missions, in collaboration with the European Space Agency (ESA), spacecraft would be sent to Mars to collect these sealed samples from the surface and return them to Earth for further study. 

The Mars 2020 Perseverance mission is part of NASA's Moon to Mars exploration strategy, which includes Artemis lunar missions to assist prepare for human exploration of Mars. 

The Perseverance rover was constructed and is operated by JPL, which is administered for NASA by Caltech in Pasadena, California. 

For additional information about Perseverance, go to: 

mars.nasa.gov/mars2020/ 

nasa.gov/perseverance

Courtesy: NASA.gov

~ Jai Krishna Ponnappan

You may also want to read more about Space Missions and Systems here.

Quantum Computing Threat to Information Security

Current RSA public-key (asymmetric) encryption systems and other versions rely on trapdoor mathematical functions, which make it simple to compute a public key from a private key but computationally impossible to compute the converse, a private key from a public key.

The difficulties of integer factorization and elliptic curve variations of the discrete logarithm issue, both of which have no known solution for computing an inverse in polynomial time, are exploited to create frequently used trapdoor functions (that is, on a finite timescale). 

In a nutshell, this so-called "computational hardness" provides safety. 

In 1994, however, Peter Shor proposed a quantum method that may be employed on a sufficiently large-scale quantum computer to perform integer factorization in polynomial time. 

The now-famous quantum technique has now been proved to solve the discrete logarithm and elliptic-curve logarithm problems in polynomial time as well. 

As a result of the creation of an FTQC in conjunction with this quantum algorithm, the security of present asymmetric public-key cryptography is jeopardized. 

Furthermore, Shor's method exemplifies how advances in the mathematics and physical sciences have the potential to jeopardize secure communications in general. 

In addition to Defense Department and critical cyber infrastructure systems, the world's digital revolution, which includes 4 billion internet users, 2 billion websites, and over $3 trillion in retail transactions, is backed at multiple tiers by existing public-key cryptography. 

While the creation of an FTQC is estimated to be at least a decade or two away, there is still a pressing need to solve this issue because of the ‘record now, exploit later' danger, in which encrypted data is collected and kept for subsequent decryption by an FTQC when one becomes available. 

As a result, the US National Institute of Standards and Technology's Post Quantum Cryptography Project, which includes worldwide partners—a security "patch" for the internet—is prioritizing the development of new "quantum hard" public-key algorithms.

Post Quantum Computing Encryption - Future-Proofing Encryption

Encryption in the post-quantum era. 

Many popular media depictions of quantum computing claim that the creation of dependable large-scale quantum computers will bring cryptography to an end and that quantum computers are just around the corner. 

The latter point of view may turn out to be overly optimistic or pessimistic, if you happen to rely on quantum-computing-proof security. 

While quantum computers have made significant progress in recent years, there's no certainty that they'll ever advance beyond laboratory proof-of-concept devices to become a realistic daily technology. (For a more thorough explanation, see a recent ASPI study.) 

Nonetheless, if quantum computing becomes a viable technology, several of the most extensively used encryption systems would be vulnerable to quantum computer cryptography assaults because quantum algorithms may drastically shorten the time it takes to crack them. 

For example, the RSA encryption scheme for the secure exchange of encryption keys, which underlies most web-based commerce, is based on the practical difficulty of finding prime factors of very big integers using classical (non-quantum) computers.

However, there is an extremely efficient quantum technique for prime factorization (known as ‘Shor's algorithm') that would make RSA encryption vulnerable to attack, jeopardizing the security of the vast quantity of economic activity that relies on the ability to safeguard moving data. 

Other commonly used encryption protocols, such as the Digital Signature Algorithm (DSA) and Elliptic Curve DSA, rely on mathematical procedures that are difficult to reverse conventionally but may be vulnerable to quantum computing assaults. 

Moving to secure quantum communication channels is one technique to secure communications. 

However, while point-to-point quantum channels are conceivable (and immune to quantum computer assaults), they have large administration overheads, and constructing a quantum ‘web' configuration is challenging. 

A traditional approach is likely to be favored for some time to come for applications such as networking military force units, creating secure communications between intelligence agencies, and putting up a secure wide-area network. 

Non-quantum (classical) techniques to data security, fortunately, are expected to remain safe even in the face of quantum computer threats. 

Quantum assaults have been found to be resistant to the 256-bit Advanced Encryption Standard (AES-256), which is routinely employed to safeguard sensitive information at rest. 

Protecting data at rest addresses only half of the problem; a secure mechanism for transferring encryption keys between the start and end locations for data in motion is still required. 

As a result, there's a lot of work being done to construct so-called "post-quantum" encryption systems that rely on mathematical processes for which no quantum algorithms exist. 

IBM has already detailed a quantum-resistant technology for safely transporting data across networks.  If the necessity arises, such a system might possibly replace RSA and other quantum-vulnerable encryption systems.

If everything else fails, there's always encryption technologies for the twenty-first century. 

One technique to improve communication security is to be able to ‘narrowcast' in such a way that eavesdropping is physically difficult, if not impossible. 

However, this is not always practicable, and there will always be messages that must pass over channels that are sensitive to eavesdropping. 

Even so-called "secure" channels can be breached at any time. 

The actual tapping of a subsea cable run to a Soviet naval facility on the Kamchatka Peninsula by the US Navy in the 1970s is a good example. The cable was deemed safe since it ran wholly within Russian territorial seas and was covered by underwater listening posts. 

As a result, it transmitted unencrypted messages. The gathered signals, though not of high intelligence value in and of themselves, gave cleartext ‘cribs' of Soviet naval communications that could be matched with encrypted data obtained elsewhere, substantially simplifying the cryptanalytic work. 

Even some of the LPI/LPD technology systems discussed in earlier sections may be subject to new techniques. 

For example, the Pentagon has funded research on devices that gather single photons reflected off air particles to identify laser signals from outside the beam, with the goal of extracting meaningful information about the beam direction, data speeds, and modulation type. The ultimate objective is to be able to intercept laser signals in the future.  

A prudent communications security approach is to expect that an opponent will find a method to access communications, notwithstanding best attempts to make it as difficult as possible. 

Highly sensitive information must be safeguarded from interception, and certain data must be kept safe for years, if not decades. Cryptographic procedures that render an intercepted transmission unintelligible are required. 

As we saw in the section on the PRC's capabilities, a significant amount of processing power is currently available to target Australian and ally military communications, and the situation is only going to become worse. 

On the horizon are technical dangers, the most well-known of which is the potential for effective quantum computing. Encryption needs to be ‘future proofed.'

As secure intermediates, space-based interconnections are used. 

If the connection can be made un-interceptable, space-based communications might provide a secure communication route for terrestrial organizations. Information and control signals between spacecraft and the Earth have been sent by radio waves to and from ground stations until now. 

Interception is achievable when collection systems are close enough to the uplink transmitter to collect energy from either the unavoidable side lobes of the main beam or when the collection system is able to be positioned inside the same downlink footprint as the receiver. 

The use of laser signals of various wavelengths to replace such RF lines has the potential to boost data speeds while also securing the communications against eavesdropping. 

Using laser communication connection between spacecraft has a number of advantages as well. 

Transmission losses over long distances restrict the efficiency with which spacecraft with low power budgets can exchange vast amounts of data, and RF connections inevitably restrict bandwidth. 

The imposts on space, weight, and power on spacecraft would be reduced if such linkages were replaced by laser communications. 

The benefits might include being able to carry larger sensor and processing payloads, spending more time on mission (owing to reduced downtime to recharge batteries), or a combination of the two. 

In the United States, the Trump administration's Space Force and anticipated NASA operations (including a presence on the moon and deep space missions) have sparked a slew of new space-based communications research initiatives. 

NASA has a ten-year project road map (dubbed the "decade of light") aiming at creating infrared and optical frequency laser communication systems, combining them with RF systems, and connecting many facilities and spacecraft into a reliable, damage-resistant network. 

As part of that effort, it is developing various technology demonstrations. 

Its Laser Communications Relay Demonstration, which is set to be live in June, will utilize lasers to encode and send data at speeds 10 to 100 times faster than radio systems.  

NASA uses the example of transmitting a map of Mars' surface back to Earth, which may take nine years with present radio technology but just nine weeks using laser communications. T

he practicality of laser communications has been demonstrated in laboratory prototype systems, and NASA plans to launch space-based versions later this year. The Pentagon's Space Development Agency (SDA) and the Defense Advanced Research Projects Agency (DARPA) are both working on comparable technologies, but with military and intelligence purposes in mind. 

The SDA envisions hundreds of satellites linked by infrared and optical laser communication connections. 

Sensor data will be sent between spacecraft until it reaches a satellite in touch with a ground station, according to the plan. Information from an orbiting sensor grid may therefore be sent to Earth in subsecond time frames, rather than the tens of minutes it can take for a low-Earth-orbiting satellite to pass within line of sight of a ground station. 

Furthermore, because to the narrow beams created by lasers, an eavesdropper has very limited chance of intercepting the message. Because of the increased communication efficiency, ‘traffic jams' in the considerably more extensively utilized radio spectrum are significantly less likely to occur. 

This year, the SDA plans to conduct a test with a small number of "cubesats." Moving to even higher frequencies, X-ray beams may theoretically transport very high data-rate messages. In terrestrial applications, ionization of air gases would soon attenuate signals, but this isn't an issue in space, and NASA is presently working on gigabit-per-second X-ray communication lines between spacecraft.  

Although NASA is primarily interested in applications for deep space missions (current methods can take many hours to transmit a single high-resolution photograph of a distant object such as an asteroid after a flyby), the technology has the potential to link future constellations of intelligence-gathering and communications satellites with extremely high data-rate channels. On board the International Space Station, NASA has placed a technology demonstration.

Communications with a low chance of being detected. 

One technique to keep communications safe from an enemy is to never send them over routes that can be detected or intercepted. For mobile force units, this isn't always practicable, but when it is, communications security may be quite effective. 

The German army curtailed its radio transmissions in the run-up to its Ardennes operation in December 1944, depending instead on couriers and landlines operating within the region it held (which was contiguous with Germany, so that command and control traffic could mostly be kept off the airwaves).

 The build-up of considerable German forces was overlooked by Allied intelligence, which had been lulled into complacency by having routinely forewarned of German moves via intercepted radio communications. 

Even today, when fibre-optic connections can transmit data at far greater rates than copper connections, the option to go "off air" when circumstances allow is still valuable. Of course, mobile troops will not always have the luxury of transferring all traffic onto cables, especially in high-speed scenarios, but there are still techniques to substantially minimize the footprint of communication signals and, in some cases, render them effectively undetectable. 

Frequency-hopping and spread-spectrum radios were two previous methods for making signals less visible to an eavesdropper. 

Although these approaches lower the RF footprint of transmissions, they are now vulnerable to detection, interception, and exploitation using wideband receivers and computer spectral analysis tools. Emerging technologies provide a variety of innovative approaches to achieve the same aim while improving security. 

The first is to use extremely directed ‘line of sight' signals that may be focused directly at the intended receiver, limiting an adversary's ability to even detect the broadcast. This might be accomplished, for example, by using tightly concentrated laser signals of various wavelengths that may be precisely directed at the desired recipient's antenna when geography allow. 

A space-based relay, in which two or more force components are linked by laser communication channels with a constellation of satellites, which are connected by secure links (see the following section for examples of ongoing work in that field), offers a difficult-to-intercept communications path. 

As a consequence, data might be sent with far less chance of being intercepted than RF signals. The distances between connecting parties are virtually unlimited for a satellite system with a worldwide footprint for its uplinks and downlinks. Moving radio signals to wavelengths that do not travel over long distances due to atmospheric absorption, but still give effective communications capabilities at small ranges, is a second strategy that is better suited to force elements in close proximity. 

The US Army, for example, is doing research on deep ultraviolet communications (UVC). 5 UVC has the following benefits over radio frequencies such as UHF and VHF: 

• the higher frequency enables for faster data transfer

• very low-powered signals can still be received over short distances

• signal strength rapidly drops off over a critical distance 

Communications with a low chance of being detected. One technique to keep communications safe from an enemy is to never send them over routes that can be detected or intercepted. 

For mobile force units, this isn't always practicable, but when it is, communications security may be quite effective. The German army curtailed its radio transmissions in the run-up to its Ardennes operation in December 1944, depending instead on couriers and landlines operating within the region it held (which was contiguous with Germany, so that command and control traffic could mostly be kept off the airwaves). 

The build-up of considerable German forces was overlooked by Allied intelligence, which had been lulled into complacency by having routinely forewarned of German moves via intercepted radio communications. 

Even today, when fiber-optic connections can transmit data at far greater rates than copper connections, the option to go "off air" when circumstances allow is still valuable. Of course, mobile troops will not always have the luxury of transferring all traffic onto cables, especially in high-speed scenarios, but there are still techniques to substantially minimize the footprint of communication signals and, in some cases, render them effectively undetectable. 

Frequency-hopping and spread-spectrum radios were two previous methods for making signals less visible to an eavesdropper. 

Although these approaches lower the RF footprint of transmissions, they are now vulnerable to detection, interception, and exploitation using wideband receivers and computer spectral analysis tools. Emerging technologies provide a variety of innovative approaches to achieve the same aim while improving security. 

The first is to use extremely directed ‘line of sight' signals that may be focused directly at the intended receiver, limiting an adversary's ability to even detect the broadcast. 

This might be accomplished, for example, by using tightly concentrated laser signals of various wavelengths that may be precisely directed at the desired recipient's antenna when geography allow. 

A space-based relay, in which two or more force components are linked by laser communication channels with a constellation of satellites, which are connected by secure links (see the following section for examples of ongoing work in that field), offers a difficult-to-intercept communications path. 

As a consequence, data might be sent with far less chance of being intercepted than RF signals. The distances between connecting parties are virtually unlimited for a satellite system with a worldwide footprint for its uplinks and downlinks. 

Moving radio signals to wavelengths that do not travel over long distances due to atmospheric absorption, but still give effective communications capabilities at small ranges, is a second strategy that is better suited to force elements in close proximity. 

The US Army, for example, is doing research on deep ultraviolet communications (UVC). 5 UVC has the following benefits over radio frequencies such as UHF and VHF: 

• the higher frequency allows for faster data transfer 

• very low-powered signals can still be heard over short distances 

• there is a quick drop-off in signal strength at a critical distance