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Archive for the ‘satellites’ category: Page 109

Apr 16, 2020

SpaceX Competitor To Launch Japanese Satellite Constellation In 2020

Posted by in category: satellites

Rocket Lab is pursuing rocket reusability using a different method than SpaceX’s self-landing rockets.

Apr 14, 2020

Exolaunch signs first launch agreement with SpaceX

Posted by in category: satellites

SAN FRANCISCO — German launch services provider Exolaunch announced plans April 14 to send multiple small satellites into orbit on a SpaceX Falcon 9 rideshare mission scheduled for December.

Exolaunch has integrated payloads and arranged launches for almost 100 satellites, but this is the company’s first launch services agreement with SpaceX, Exolaunch Commercial Director Jeanne Medvedeva told SpaceNews.

“Participation in SpaceX’s smallsat rideshare program will allow Exolaunch to offer reliable and cost efficient rideshare options out of the United States,” Medvedeva said by email. “Most of our customers have been proactively requesting such opportunities.”

Apr 14, 2020

How Do You Shield Astronauts and Satellites From Deadly Micrometeorites?

Posted by in category: satellites

Circa 2013

Apr 11, 2020

Chinese Launched Satellite Seen Crashing Back to Earth Over Guam, USA

Posted by in categories: astronomy, satellites, science, space, space travel

From the US territory Guam, sightings came in of a fireball falling from the sky. The strategic location of Guam and the U.S. military stationed there has drawn attention for years. Guam thrust into the limelight during heightened tensions with North Korea. In August 2017, North Korea launched missiles that flew over Japan and into the northern Pacific Ocean in an apparent attempt to threaten the US territory of Guam. North Korean leader Kim Jong Un did not follow up on his threats, but a fireball came crashing down from a different source.

Local officials quickly released an announcement indicating the Chinese Long March Launch as a likely source of the fireball. Indeed, an Indonesia satellite launched on a Chinese rocket came crashing back to Earth. The satellite failed to reach orbit. The failure of the new communications satellite for Indonesia to reach orbit marked the second failure for china’s space agency in less than a month, state media reported April 9.

It is unlike the Chinese Long March 3, workhorse of the Chinese launch industry, series rocket to fall. According to the Xinhua News Agency, the rocket lifted off at 7:46 p.m local time from China’s Xichang Satellite Launch Center in the Sichuan province. The rocket traveled according to plan during the first and second stages. The Rocket third stage experienced abnormal conditions.

Continue reading “Chinese Launched Satellite Seen Crashing Back to Earth Over Guam, USA” »

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.