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Archive for the ‘satellites’ category: Page 122

Apr 9, 2020

Scientists use the Tokyo Skytree to test Einstein’s theory of general relativity

Posted by in category: satellites

In another verification of the validity of Einstein’s theory of general relativity, published in Nature Photonics, scientists from the RIKEN Center for Advanced Photonics and Cluster for Pioneering Research, with colleagues, have used two finely tuned optical lattice clocks, one at the base and one on the 450-meter observatory floor of Tokyo Skytree, to make new ultraprecise measurements of the time dilation effect predicted by Einstein’s theory of general relativity.

Einstein theorized that the warping of time-space by gravity was caused by massive objects. In line with this, time runs more slowly in a deep gravitational field than in a shallower one. This means that times runs slightly more slowly at the base of the Skytree tower than at the top.

The difficulty with actually measuring the change in how quickly clocks run in different gravity field is that the difference is very small. Performing a stringent test of the theory of requires either a very precise clock or a large difference in height. One of the best measurements so far has involved large and complex clocks such as those developed by the RIKEN group, which can measure a difference of around a centimeter in height. Outside the laboratory, the best tests have been taken by satellites, with altitudes that are thousands of kilometers different. Such space experiments have constrained any violation of to about 30 parts per million, a tremendously precise measurement that essentially shows Einstein to be correct.

Apr 7, 2020

This Breakthrough Just Got Us One Step Closer to a Quantum Internet

Posted by in categories: internet, military, quantum physics, satellites

The US is well behind China on this front, though. A team led by quantum supremo Jian-Wei Pan have already demonstrated a host of breakthroughs in transmitting quantum signals to satellites, most recently developing a mobile quantum satellite station.

The reason both countries are rushing to develop the technology is that it could provide an ultra-secure communication channel in an era where cyberwarfare is becoming increasingly common.

I t’s essentially impossible to eavesdrop on a quantum conversation. The strange rules of quantum mechanics mean that measuring a quantum state immediately changes it, so any message encoded in quantum states will be corrupted if someone tries to intercept it.

Apr 6, 2020

Small Satellites are Expanding

Posted by in categories: satellites, space

Satellites come in all sizes and shapes. A small satellite or SmallSat is commonly considered to be a satellite that weighs less than 500 kg.

As a basic application of various satellite sizes by mass, the common distinction:

Lower LimitUpper Limit(kg)ClassificationExamples
1000Large satellitesHubble Space Telescope / Inmarsat-4A F4
5001000Medium satellitesO3b
0500Small satellitesSpaceX StarLink
Short Summary of Satellite sizes

CubeSats are smaller yet.

CubeSats need to conform to specific criteria including shape, size, and mass. At this point, most people have become aware or are at least heard of CubeSats. (Cube Satellites). CubeSats (cube satellite, cube satellite) are a type of nanosatellites defined by the CubeSat Design Specification (CSD) or otherwise commonly known by the unofficial term “CubeSat standard”. Cubesats are small, and start off at the 1U size of 10xm x 10 cm x 11.35 cm ( yes not exactly a cube, but very close) Here are some standard CubeSat dimensions:

Continue reading “Small Satellites are Expanding” »

Apr 1, 2020

The world’s largest aircraft will now test hypersonics for the military

Posted by in categories: government, military, satellites

“Our hypersonic testbeds will serve as a catalyst in sparking a renaissance in hypersonic technologies for our government, the commercial sector, and academia,” said W. Jean Floyd, Stratolaunch’s chief executive, in a statement.

This is an interesting, if not wholly unexpected, turn for Stratolaunch. During the last decade, the aerospace community has often collectively scratched its head, wondering how such a large aircraft could be cost-competitive in the hotly contested market to launch small- and medium-sized satellites. And without a dedicated rocket in existence, the company seemed little more than a vanity project for the wealthy Allen. If Stratolaunch served any purpose, the speculation went, it must be to meet some unspecified military need.

There can be no question that the military is interested in hypersonic technology. China, Russia, and the United States are all racing to develop hypersonic missiles, as well as new countermeasure technology as high-speed missiles threaten to penetrate most existing defenses. A Rand Corporation report from 2017 provides more basic information, suggesting, “There is probably less than a decade available to substantially hinder the potential proliferation of hypersonic missiles and associated technologies.”

Apr 1, 2020

U-M leads $62M ‘largest radio telescope in space’ to improve solar storm warnings

Posted by in categories: particle physics, satellites

ANN ARBOR—The most violent solar weather—coronal mass ejections—can flood space with high-energy particle radiation that would harm astronauts and damage spacecraft in its path..

A new $62.6 million NASA mission led by the University of Michigan aims to provide better information on how the sun’s radiation affects the space environment that our spacecraft and astronauts travel through.

The Sun Radio Interferometer Space Experiment, or SunRISE, consists of miniature satellites called cubesats that form a “virtual telescope” in space to detect and study the radio waves that precede major solar events. The waves can’t be detected on Earth’s surface due to interference from the region of Earth’s upper atmosphere known as the ionosphere.

Mar 30, 2020

Stars and Starlink

Posted by in categories: biotech/medical, finance, satellites

Astronomers may have one less (satellite) constellation to worry about.

Late Friday, OneWeb announced it had filed for Chapter 11 bankruptcy in a New York court. In a statement, the company said it had been in “advanced negotiations” since the beginning of the year to raise a new round of funding needed to complete its broadband satellite constellation. The company said it was close to completing that deal, but “the financial impact and market turbulence related to the spread of COVID-19” kept it from closing the deal.

OneWeb had just started large-scale deployment of its constellation, with Soyuz launches in early February and again March 21 each placing 34 satellites into orbit. Future launches are now on hold—launch services provider Arianespace was the largest single unsecured creditor identified in OneWeb’s bankruptcy, at $238 million—and may never resume, depending on who buys the company’s assets in a planned sale and their intentions for them.

Mar 28, 2020

SpaceX going to the Moon with NASA

Posted by in categories: astronomy, complex systems, disruptive technology, Elon Musk, satellites, space, space travel
Orion and Dragon XL near the Lunar Gateway Credit: NASA

By Bill D’Zio, Originally posted on www.westeastspace.com March 28, 2020

NASA may have sidelined the Lunar Gateway for a return mission to the Moon, but it is not stopping the momentum. NASA has awarded several contracts for the Lunar Gateway including the most recent one to SpaceX. This demonstrates the growing capabilities of New Space companies to capture contracts and complete missions.

This contract award is another critical piece of our plan to return to the Moon sustainably. The Gateway is the cornerstone of the long-term Artemis architecture and this deep space commercial cargo capability integrates yet another American industry partner into our plans for human exploration at the Moon in preparation for a future mission to Mars.NASA Administrator Jim Bridenstine in a press release statement about the award to SpaceX.

NASA Awarded SpaceX the first Artemis Gateway Logistics Services (GLS) contract. The award for resupply services to the Gateway will require delivery of goods to a Near Rectilinear Halo Orbit (NRHO). Not sure what a NRHO orbit is? A NRHO is a highly elliptical orbit that takes about 7 days for each orbit. Want some more details, just click here: Near Rectilinear Halo Orbit (NRHO). There are a few options for NRHO orbits, but NASA is leaning towards the L2 9:2 lunar synodic resonant southerly Near-Rectilinear Halo Orbit (NRHO) which would be the likely location of the lunar Gateway. A simplification of the orbit is shown below.

Continue reading “SpaceX going to the Moon with NASA” »

Mar 27, 2020

New satellite views show impact of coronavirus on emissions, China’s night lights

Posted by in categories: biotech/medical, satellites

Satellites are studying the impacts on pollution and night lighting of measures taken to slow the spread of COVID-19.

Mar 24, 2020

Space in uncertain times

Posted by in categories: biotech/medical, economics, satellites, sustainability

Last month, even as the coronavirus epidemic was ravaging China and making inroads in other nations, the space industry’s concerns were elsewhere. There were debates about a NASA authorization bill in the House that would reshape NASA’s Artemis program even as the agency sought more money for it, the ongoing review into the flawed test flight of Boeing’s CST-100 Starliner commercial crew vehicle, renewed concerns about orbital debris after a close call between two defunct satellites, and discussions about the viability and sustainability of satellite constellations like OneWeb and SpaceX’s Starlink as both moved into full-scale deployment.

Those were the days. In the last couple of weeks, and especially in the last week, those issues have largely disappeared as what is now a pandemic takes hold in the United States and many other nations. But while many parts of the economy have ground to a halt, like retail and tourism, the effects on the space industry have been uneven. Some parts of it have also effectively halted, yet others continue ahead at essentially full speed—at least for now.

The first clear signs of the effects of the pandemic on the industry was bringing the circuit of conferences and other events to a standstill. On March 9, the Satellite 2020 conference got underway in Washington despite growing concerns about the spread of the coronavirus disease COVID-19, including the first cases diagnosed in the city. Conference organizers plowed ahead even as some major companies, like satellite operator SES, bowed out, saying only about 10 percent of attendees as 12 percent of exhibitors had cancelled their plans.

Mar 22, 2020

DARPA is Building a Robotic Space Mechanic to Fix Satellites in Orbit

Posted by in categories: biotech/medical, food, military, robotics/AI, satellites

DARPA, the Defense Advanced Research Projects Agency that’s responsible for developing emerging technologies for the U.S. military, is building a new high-tech spacecraft — and it’s armed. In an age of Space Force and burgeoning threats like hunter-killer satellites, this might not sound too surprising. But you’re misunderstanding. DARPA’s new spacecraft, currently “in the thick of it” when it comes to development, is armed. As in, it has arms. Like the ones you use for grabbing things.

Armed robots aren’t new. Mechanical robot arms are increasingly widespread here on Earth. Robot arms have been used to carry out complex surgery and flip burgers. Attached to undersea exploration vehicles, they’ve been used to probe submerged wrecks. They’ve been used to open doors, defuse bombs, and decommission nuclear power plants. They’re pretty darn versatile. But space is another matter entirely.