CodeRedR51
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One of the FH boosters is on display at the Kennedy Space Center until the 20th. Just in case you are in that area.
I wonder how much that pair of cradles costs...
Someone in a SpaceX group said they bought them from NASA for the ridiculously cheap sum of $37k each.I wonder how much that pair of cradles costs...
That is pretty ridiculous for something that has to be capable of doing what they do. Of course the intersection of "need money" and "no longer need this thing" lends itself to figures like that. Really, I expected they were purpose-built by SpaceX (which makes finding a figure more difficult) or built for them by another firm (which seemed unlikely given what I know of SpaceX).Someone in a SpaceX group said they bought them from NASA for the ridiculously cheap sum of $37k each.
All I see is a column of yellow light. Are we sure it isn't someone with a power ring letting loose the power of fear?
That is pretty ridiculous for something that has to be capable of doing what they do. Of course the intersection of "need money" and "no longer need this thing" lends itself to figures like that. Really, I expected they were purpose-built by SpaceX (which makes finding a figure more difficult) or built for them by another firm (which seemed unlikely given what I know of SpaceX).
Oh, no, I get that...that's exactly why I mentioned the "intersection."It's one those things where really, who else is going to buy them? NASA is lucky they get to sell them at all. $37k is basically a peppercorn.
You can have something that's incredibly valuable on paper, but if no one wants to buy it the actual sale value is zero.
THE WORSENING COSMIC RAY SITUATION: Cosmic rays are bad–and they're getting worse. That's the conclusion of a new paper just published in the research journal Space Weather. The authors, led by Prof. Nathan Schwadron of the University of New Hampshire, show that radiation from deep space is dangerous and intensifying faster than previously predicted.
The story begins four years ago when Schwadron and colleagues first sounded the alarm about cosmic rays. Analyzing data from the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument onboard NASA's Lunar Reconnaissance Orbiter (LRO), they found that cosmic rays in the Earth-Moon system were peaking at levels never before seen in the Space Age. The worsening radiation environment, they pointed out, was a potential peril to astronauts, curtailing how long they could safely travel through space.
This figure from their original 2014 paper shows the number of days a 30-year old male astronaut flying in a spaceship with 10 g/cm2 of aluminum shielding could go before hitting NASA-mandated radiation limits:
In the 1990s, the astronaut could spend 1000 days in interplanetary space. In 2014 … only 700 days. "That's a huge change," says Schwadron.
Galactic cosmic rays come from outside the solar system. They are a mixture of high-energy photons and sub-atomic particles accelerated toward Earth by supernova explosions and other violent events in the cosmos. Our first line of defense is the sun: The sun's magnetic field and solar wind combine to create a porous 'shield' that fends off cosmic rays attempting to enter the solar system. The shielding action of the sun is strongest during Solar Maximum and weakest during Solar Minimum–hence the 11-year rhythm of the mission duration plot above.
The problem is, as the authors note in their new paper, the shield is weakening: "Over the last decade, the solar wind has exhibited low densities and magnetic field strengths, representing anomalous states that have never been observed during the Space Age. As a result of this remarkably weak solar activity, we have also observed the highest fluxes of cosmic rays."
Back in 2014, Schwadron et al used a leading model of solar activity to predict how bad cosmic rays would become during the next Solar Minimum, now expected in 2019-2020. "Our previous work suggested a ~ 20% increase of dose rates from one solar minimum to the next," says Schwadron. "In fact, we now see that actual dose rates observed by CRaTER in the last 4 years exceed the predictions by ~ 10%, showing that the radiation environment is worsening even more rapidly than we expected." In this plot bright green data points show the recent excess:
The data Schwadron et al have been analyzing come from CRaTER on the LRO spacecraft in orbit around the Moon, which is point-blank exposed to any cosmic radiation the sun allows to pass. Here on Earth, we have two additional lines of defense: the magnetic field and atmosphere of our planet. Both mitigate cosmic rays.
But even on Earth the increase is being felt. Spaceweather.com and the students of Earth to Sky Calculus have been launching space weather balloons to the stratosphere almost weekly since 2015. Sensors onboard those balloons show a 13% increase in radiation (X-rays and gamma-rays) penetrating our planet's atmosphere:
X-rays and gamma-rays detected by these balloons are "secondary cosmic rays," produced by the crash of primary cosmic rays into Earth's upper atmosphere. They trace radiation percolating down toward our planet's surface. The energy range of the sensors, 10 keV to 20 MeV, is similar to that of medical X-ray machines and airport security scanners.
How does this affect us? Cosmic rays penetrate commercial airlines, dosing passengers and flight crews so much that pilots are classified by the International Commission on Radiological Protection as occupational radiation workers. Some research shows that cosmic rays can seed clouds and trigger lightning, potentially altering weather and climate. Furthermore, there are studies ( #1, #2, #3, #4) linking cosmic rays with cardiac arrhythmias in the general population.
Cosmic rays will intensify even more in the years ahead as the sun plunges toward what may be the deepest Solar Minimum in more than a century. Stay tuned for updates.
I'm intrigued by what's going on on the left side of the column...
A flip in Earth's magnetic field may be brewing. And if it is, an electromagnetic blob deep under southern Africa is likely to be ground zero for the change.
New research using clays burned in cleansing rituals by Iron Age farmers finds that over the past 1,500 years, an electromagnetic anomaly in the Southern Hemisphere has waxed and waned, with the magnetic field in the region weakening and strengthening. This weirdness may presage a gradual reversal in the magnetic field, so that magnetic north moves to the South Pole and vice versa. (A flip-flop of this sort last occurred 780,000 years ago.)
The study suggests that the magnetic field under southern Africa may not just be weird today, study co-author John Tarduno, who researches the Earth's magnetism at the University of Rochester in New York, told Live Science. It may be a longstanding hotspot for changes in the global magnetic field.
"This may be the place that reversal started, at least reversals over the last millions of years," Tarduno said. [7 Ways the Earth Changes in the Blink of an Eye]
Weakening field
The planet's magnetic field is generated by the churning of liquid iron in the core. Without the field, life on the planet would be much different, if not impossible: This invisible shield protects the Earth's surface from deadly cosmic radiation.
Right now, the field is undergoing a weakening, and no one is sure why. The South Atlantic Anomaly, a region of the magnetic field that stretches from South Africa to Chile, is particularly weak, Tarduno said, so scientists have become interested in figuring out what might be going on in the core underneath that area.
The problem is that before about 160 years or so ago, with the advent of magnetic observatories and (eventually) satellite observations, there weren't many records of what the magnetic field looked like in the Southern Hemisphere, Tarduno said. Ninety percent of the data that does exist comes from the northern half of the planet. To start to rectify that disparity, Tarduno and his team excavated clays from the Limpopo River Valley of Zimbabwe, South Africa, and Botswana. In times of drought hundreds to thousands of years ago, Bantu-speaking farmers would burn down their clay huts and grain bins in ritualistic ceremonies. Unbeknown to these ancient farmers, the fire heated the magnetic minerals in the clay and locked into place a record of the strength and orientation of the field at that time. Now, researchers can study those properties to find out what the magnetic field was doing at that moment in time.
Locked in clay
The excavations unearthed these burnt clays as long ago as A.D. 425, Tarduno said, providing the longest record yet of the magnetic field in southern Africa. The data show that the magnetic field experienced sudden directional shifts between A.D. 400 and 450, and then again between A.D. 750 and 800. Between about A.D. 1225 and 1550, the field noticeably weakened. The first two shifts might also indicate a weakened field, Tarduno said, but more research is needed to determine the magnetic intensity in those time frames. The researchers reported their findings Feb. 15 in the journal Geophysical Research Letters.
What these shifts suggest is that what is going on in the Southern Hemisphere's magnetic field today may have happened before, Tarduno said.
The field shifts may have to do with underlying processes churning deep beneath the Earth's surface, Tarduno said. In recent years, scientists have documented a weird patch of magnetic field below southern Africa at the boundary between the core and the mantle, where the polarity of the field is reversed.
"That patch may be largely responsible for the decreasing magnetic field," Tarduno said.
The patch is like an eddy in a stream, he said. As for what causes the eddy, it may be something odd about the mantle right above the core in that location, he said. The mantle under southern Africa is unusual, and possibly both hotter and denser than surrounding mantle, he said.
"We think that is causing there to be changes in the flow of the iron [in the core] as it enters this region," Tarduno said.
That could mean that southern Africa is the origin for magnetic field reversals, Tarduno said, though there's no guarantee that the field will flip now — the weakening could also dissipate, as it has in centuries past.
Even if the field doesn't reverse, though, the weakening itself could have societal implications, Tarduno said.
"These are not of the nature of disaster movies. That's not the point," he said. Instead, a weakening field could let more cosmic radiation hit the Earth, making infrastructure like the power grid more susceptible to geomagnetic storms and even changing atmospheric chemistry so that more UV rays could sneak through, causing increased risk for skin cancer in humans.
"It's definitely something that we need to keep an eye on," Tarduno said.
Original article on Live Science.
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I'm intrigued by what's going on on the left side of the column...
Those swirls of orange fire.What exactly are you intrigued about?
Those swirls of orange fire.
The catalog just got a little messier.12 new images have been added to the Hubble Messier Catalog. New images are marked as "New" on that page.
The full catalog is available in high resolution HERE.
What's usual?An unusual object on Mars
I posted this because of the remarks NASA made about it. At first they thought it might be your lost Beagle. But it's the wrong shape and not in the right location. They consulted both their internal and external photo analysis people, and concluded that it was unexplained. IMO, it is no more or less unusual than the many other oddities found on the Red Planet. IMO, Mars is currently lifeless.That could be a number of objects - look at the terrain lines to the left of the object, you can follow them through. I think our brains are making a composite from those objects.