SpaceX has promised that future Starlink satellites will have sunshades so they don’t blocks astronomers’ views of the stars.
Category: satellites – Page 131
Speed as important as size in predicting potentially damaging impacts of coronal mass ejections.
Space weather forecasters need to predict the speed of solar eruptions, as much as their size, to protect satellites and the health of astronauts, scientists have found.
Scientists at the University of Reading found that by calculating the speed of coronal mass ejections (CMEs) when they hit Earth, forecasters could provide more useful early warnings. This would help operators of critical infrastructure such as satellites know if they need to take evasive action or switch off systems to protect them, and warn astronauts when they need to shelter inside shielded parts of the International Space Station.
Miniaturization has enabled technology like smartphones, health watches, medical probes and nano-satellites, all unthinkable a couple decades ago. Just imagine that in the course of 60 years, the transistor has shrunk from the size of your palm to 14 nanometers in dimension, 1000 times smaller than the diameter of a hair.
Miniaturization has pushed technology to a new era of optical circuitry. But in parallel, it has also triggered new challenges and obstacles, for example, controlling and guiding light at the nanometer scale. Researchers are looking for techniques to confine light into extremely tiny spaces, millions of times smaller than current ones. Studies had earlier found that metals can compress light below the wavelength-scale (diffraction limit).
In that aspect, graphene, a material composed from a single layer of carbon atoms, which exhibits exceptional optical and electrical properties, is capable of guiding light in the form of plasmons, which are oscillations of electrons that strongly interact with light. These graphene plasmons have a natural ability to confine light to very small spaces. However, until now, it was only possible to confine these plasmons in one direction, while the actual ability of light to interact with small particles like atoms and molecules resides in the volume into which it can be compressed. This type of confinement in all three dimensions is commonly regarded as an optical cavity.
After SpaceX’s eighth Starlink internet satellite launch, the company released a video of its Falcon 9 rocket jettisoning two $3 million fairings.
SpaceX’s Starlink satellite constellation is still deep into testing mode, but it’s already generating 5 trillion bytes of data on a daily basis and getting software updates on a weekly basis.
Those are a couple of the nuggets coming from a weekend Reddit “Ask Me Anything” session featuring SpaceX’s software team.
The main focus of the online chat was SpaceX’s successful mission sending NASA astronauts Bob Behnken and Doug Hurley to the International Space Station in a Crew Dragon capsule — but one of the team members, Matt Monson, has moved on from Dragon to take charge of Starlink software development.
Changing Course
The Air Force announced an AI initiative called “Skyborg” last March with the goal of flying fighter jets without anyone at the controls. Now, Shanahan says that the Air Force may be more interested in swarm drones and other uses for AI than necessarily taking the pilot out of a fighter plane’s cockpit.
“Maybe I shouldn’t be thinking about a 65ft-wingspan, maybe it is a small autonomous swarming capability,” Shanahan told BBC News. “The last thing I would claim is that carriers and fighters and satellites are going away in the next couple of years.”
SpaceX will launch its next batch of Starlink internet satellites into orbit tonight (June 3) after two weeks of weather delays and the company’s historic first astronaut flight.
A Falcon 9 rocket, which SpaceX has already flown four past missions, will launch 60 new Starlink satellites into orbit from the company’s pad at Launch Complex 40 at Cape Canaveral Air Force Base in Florida. Liftoff is set for 9:25 p.m. EDT (0125 June 4 GMT).
Researchers at Universidad Carlos III de Madrid (UC3M) have patented a new spatial plasma-fueled engine capable of satellite and spacecraft propulsion, with magnetic field geometry and configuration that would minimize losses on walls and their erosion, thereby resolving issues of efficiency, durability, and operating restrictions of engines that are currently in orbit.
Researchers at the University of Science and Technology of China have recently introduced a new satellite-based quantum-secure time transfer (QSTT) protocol that could enable more secure communications between different satellites or other technology in space. Their protocol, presented in a paper published in Nature Physics, is based on two-way quantum key distribution in free space, a technique to encrypt communications between different devices.
“Our main idea was to realize quantum-secure time transfer in order to resolve the security issues in practical time–frequency transfer,” Feihu Xu, one of the researchers who carried out the study, told Phys.org.
Quantum key distribution (QKD) is a technique to achieve secure communication that utilize cryptographic protocols based on the laws of quantum mechanics. Quantum key distribution protocols can generate secret security keys based on quantum physics, enabling more secure data transfer between different devices by spotting attackers who are trying to intercept communications.