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Submission + - Chandrayaan 2, Indian Spacecraft, Enters Moon's Orbit (ctvnews.ca)

William Robinson writes: An unmanned spacecraft, Chandrayaan 2, India launched last month has begun orbiting the moon before it lands on the far side to search for water. The spacecraft is in orbit of 114 km x 18072 km and will continue circling the moon in a tighter orbit until reaching a distance of about 100 km x 30 km from the moon's surface. The lander will then separate from the orbiter and use rocket fuel to brake as it attempts to land in the south polar region of the moon on Sept. 7. The mission is carrying a total of 14 payloads—13 Indian and one passive payload from Nasa—with special focus of the orbiter on mapping craters in the polar region, besides checking for water again.

Submission + - SpaceX Starship Mk 2 Plans for Cocoa - KSC Move Leaked

RhettLivingston writes: Real plans for the move of Starship Mk 2 from its current construction site in Cocoa to KSC have finally emerged. A News 6 Orlando report identifies permit applications and observed preparations for the move which will take a land and sea route.

Barring some remarkably hasty road compaction and paving, the prototype will start its journey off-road, crossing a recently cleared path through vacant land to reach Grissom Parkway. It will then travel east in the westbound lanes of SR 528 for a short distance before loading to a barge in the Indian river via a makeshift dock. The rest of the route is relatively conventional, including offloading at KSC at the site previously used for delivery of the Space Shuttle's external fuel tanks.

Given the recent construction of new facilities at the current construction site, it is likely that this will not be the last time this route is utilized.

Submission + - FAA Considers Relaxing Licensing Requirements for Rockets (regulations.gov)

apoc.famine writes: In a proposed change to the licensing of spaceflight operations, the FAA writes:

"This action would fundamentally change how the FAA licenses launches and reentries...by proposing a regulatory approach that relies on performance-based regulations rather than prescriptive regulations.....This action would also enable flexible timeframes, remove unnecessary ground safety regulations, redefine when launch begins to allow specified pre-flight operations prior to license approval, and allow applicants to seek a license to launch from multiple sites. This proposal would significantly streamline and simplify licensing of launch and reentry operations, would enable novel operations, and would result in net cost savings."

The proposal is out for public comment at the link provided. Numerous companies engaged in spaceflight operations (ULA, Boeing, Blue Origin, Sierra Nevada, etc.) have requested clarifications about what this proposal means. Concerns about public safety are understandably being voiced as well.

Submission + - Cerebras Systems Unveils a Record 1.2 Trillion Transistor Chip For AI (venturebeat.com)

An anonymous reader writes: New artificial intelligence company Cerebras Systems is unveiling the largest semiconductor chip ever built. The Cerebras Wafer Scale Engine has 1.2 trillion transistors, the basic on-off electronic switches that are the building blocks of silicon chips. Intel’s first 4004 processor in 1971 had 2,300 transistors, and a recent Advanced Micro Devices processor has 32 billion transistors. Samsung has actually built a flash memory chip, the eUFS, with 2 trillion transistors. But the Cerebras chip is built for processing, and it boasts 400,000 cores on 42,225 square millimeters. It is 56.7 times larger than the largest Nvidia graphics processing unit, which measures 815 square millimeters and 21.1 billion transistors. The WSE also contains 3,000 times more high-speed, on-chip memory and has 10,000 times more memory bandwidth.

Comment Re:X-Ray Film stock versus Digital Imager (Score 1) 138

Film vs digital detector doses are comparable, but when you factor in repeats due to improper exposures, film is a little higher. It's not enough to make it worth switching to digital detectors based on dose considerations alone though. There are plenty more compelling reasons to switch from film to digital.

The wider dynamic range of digital detectors gives a lot of flexibility when it comes to the amount of exposure used. If not enough radiation is used, a digital detector will produce a noisier, but often still useful image. The film image on the other hand will be too light and generally non-diagnostic. If too much radiation is used, the digital detector will produce a pretty, low noise image where the film image will end up being too dark and often non-diagnostic.

Comment the need for proper imaging protocols (Score 1) 138

It is ultimately the responsibility of the imaging professionals (radiologists, technologists and medical physicists) to develop proper imaging protocols to suit the age and sizes of the patients being imaged, not only from a radiation dosimetry point of view, but also an image quality point of view.

For a long time now the tendency, particularly with CT imaging, has been to use a one size fits all protocol for everybody.

The move to reducing medical radiation exposure has been going on for several years now. Recent high profile incidents (such as what happened with CT patients getting CT angiograms at Cedars Sinai) prompted many institutions to review their imaging protocols. The Image Gently campaign has worked towards getting institutions to develop pediatric specific imaging protocols for several years now. For procedures involving potentially high radiation exposures, radiologists review and protocol the requests to make sure the requested exam fits the clinical indications. Outpatient imaging centers performing CT imaging need to get their scanners accredited in order to get Medicare reimbursement. Accreditation by the ACR (American College of Radiology) places dose limits on several types of scans. If a site's protocol results in a radiation dose that exceeds the limits, they fail accreditation and need to adjust their protocols.

The FDA can and should require manufacturers provide the tools to enable imaging facilities to monitor and record the amount of radiation given during a procedure, but it needs to be the responsibility of the users to make sure the imaging equipment is used properly on patients.

Comment the best camera (Score 5, Insightful) 569

is the one that you carry with you.

for a photography newbie, i'm of the opinion that the specific camera doesn't really matter. They're all more or less the same anyway. what's most important is finding one that you'll want to carry around with you and use. the more you use it the less newb you'll become over time. you'll learn things and by the time you're ready to upgrade you'll know what to look for.

Comment Saw it last night (Score 1) 239

and rather enjoyed it. The ending was different from what I expected or thought it might be, but given the nature of apes, a much more fitting ending than the one I imagined.

the only people the apes kill are the ones that deserved it. on the other side, lots of apes were killed by people.

Comment Re:You've taken the idea and got it backwards (Score 1) 199

This has been known for decades. The more time at altitude the LESS you should be exposed to other forms of radiation. That's why they ask you questions about flying before any medical procedure involving radiation.
I'll bet the pilots are incredibly pissed about all these scans because for one thing it can reduce their legal flight time.

In the US, medical exposures are not counted against occupational exposure.

To make things worse these things are not just your normal transmission x-ray where you just want to see what photons make it to the sensor and the dark spots tell you where the dense stuff is. What these scanners are doing is providing far more radiation with the aim of getting atoms to absorb and re-emit photons - effectively making you radioactive while the scanner is on. The idea behind that is the wavelengths of the re-emitted photons can be used to determine what elements are present, find metal and perhaps find explosives. Because that really adds up to a shitload of radiation if it's going to scan all the way through you the dose is cut back and you just end up with the skin being exposed to quite a lot and no ability to sense internally hidden explosives.

No. The x-rays being detected are those that scatter off the person being scanned. They are *not* making anybody radioactive in any way. There is no way scattered x-rays are going to tell you the elemental composition of anything. Density, but not composition.

It is also not a "shitload of radiation". If these machines were detecting transmitted radiation instead, that would actually require *more* radiation exposure and would operate more like x-ray units found in hospitals.

Submission + - Six Atari 2600 "vaporware" games from 1983 found! (digitpress.com)

Anonymous Coward writes: "Six previously unreleased Atari VCS/2600 games that were developed by Jerry Lawson’s company, Video Soft, are at last being released! The games were mentioned in press releases from the early 1980s and were long thought to have been just one of the many vaporware titles that never materialized. Not only do they exist in prototype form, but all were far enough along in development to be playable, with half of them considered to be complete!

Thanks to Jerry Lawson and the efforts of a few, dedicated Atari fans, the prototypes were archived, new artwork was created, and cartridges were produced. Each includes both a box and manual, and production is limited to 100 numbered copies of each title. Only 100 of each will ever be produced. This is the single-largest cache of unreleased Atari VCS/2600 prototypes to ever be released at one time!"

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