Salute Our Space Heroes


Traveling in outer space sounds fun. Being an astronaut seems to be an exciting career. Until the gringa is reminded about space radiation. Those heavy duty marshmallow looking suits astronauts wear are not just to keep them warm, properly pressurized and surrounded by oxygen. They also protect against dangerous space radiation. But is it enough? Are spacecrafts and the International Space Station adequately protected or are our astronauts slowly being radiated to death?

Radiation is an invisible energy form of high-speed particles and electromagnetics. It surrounds humans in everyday artificial light, sunlight, and electronics that produce radio-, television-, and micro- waves. Radiation comes in two forms:

  • Ionized: This is the worst in the form of gamma rays, protons and neutrons. Exposure to ionized radiation results in exposed atoms becoming unstable by an energy powerful enough to remove electrons from their orbit around the atom’s nucleus.
  • Non-ionized: Not powerful enough to destabilize atoms, this is the kind of common radiation produced by microwaves, radio waves and light.

The radiation in space is, unfortunately, comprised of ionized radiation. There are three things that typically create dangerous space radiation:

  • Trapped radiation: The Earth’s core creates a magnetic field that surrounds our planet up to several thousand kilometers from our planet’s surface. Solar wind carries charged particles that slam into our magnetic shield. Some particles manage to pass through. Those that don’t create a shockwave that deflects from Earth’s magnetic field. This creates layers of cavities called the “magnetosphere” that act as shock absorbers to protect Earth further from charged particle bombardment. But some particles get trapped in these cavities and they become radioactive belts surrounding Earth. Astronauts have to pass through these dangerous belts before they reach deeper space.
  • Galactic Cosmic Radiation (GCR): Outside our solar system ionized atoms traveling at almost light speed pass through space matter, including humans and man-made objects unless they are properly shielded.
  • Solar Particle Events (SPE): Sometimes the Sun flares and ejects copious amounts of highly charged radioactive particles into space. These particles travel so fast they are capable of reaching Earth within ten minutes of a solar or coronal flare event. These are dramatic happenings that temporarily drastically increase radiation exposure.

Astronauts traveling through space radiation or living in the ISS have to be protected from space radiation. Radiation exposure causes damage to human cells. There is a scientific formula used to calculate how much radiation exposure an astronaut can expect when working on the ISS. It’s a bit too complicated for the gringa to understand. These calculations are the reason ISS missions have a maximum six month cycle and spacewalks are limited. Exposure is increased during a spacewalk to perform repairs and maintenance.

Shielding is preferred to be constructed of materials like polyethylene because it has a high hydrogen content. This kind of material is more effective than metals at reducing the ability of particles to pass through and enter the modules. Astronauts also wear monitors called “dosimeters” that constantly measure the level of radiation damage to the chromosomes in their blood cells.

Every single astronaut is a hero. No matter what the duration of their mission. No matter what the nature of their mission. No matter what it is they did, whether it seemed glamorous or insignificant, these men and women are heroes of science. They are risking their lives every moment they are off the surface of the Earth. Even if they return safely, they have still sacrificed much. From musculo-skeletal issues to organ damage and higher cancer risks, every single astronaut will experience the effects of radiation exposure for a lifetime despite the measures taken to protect them. If you ever meet an astronaut thank them for their invaluable sacrifice and service performing critical scientific endeavors that are helping us understand our origins, learn about climate change conditions and create solutions to save our homeworld.

Sources:

jsc.nasa.gov

spaceflight.nasa.gov

Image source:  antarcticglaciers.org

 

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The Case Of The Missing Matter


Some time back the gringa wrote about dark matter. This is invisible stuff in the universe that we only knows exists because of its gravitational affect upon other objects in space. Now scientists have a bit of a conundrum. It’s not bad enough that we have to accept the reality of lots of invisible stuff surrounding us but we also have to deal with the mystery that some of this stuff has just disappeared. Scientists want to know just where all this missing matter has got to. This is what they call the “global missing baryon problem”.

The easiest explanation of the “global missing baryon problem” goes something like this:

Baryon – this is a subatomic particle that has a mass equal to or greater than a proton. Despite the fact that the universe is incredibly vast, scientists, through mathematical formulas using their knowledge of how many protons are found in specific types of matter, can actually calculate how many atoms, protons, electrons, neutrons and baryons should be present in a galaxy. It seems that the expected number of baryons is coming up short. The baryon shortfall affects visible matter as well as dark matter.

The gringa would like to know just where the heck these baryons have gotten to and does it really matter in the grand scheme of things? I mean, am I going to wake up tomorrow and discover that half my ear is missing, or my flower pot has disappeared? Dear reader, you understand what I’m talking about. Is this something that we should really be worried about or is it just an enigmatic puzzle for scientists to puzzle over?

Australian astronomers from the Compact Array station claim that they know what has happened to the baryons. They believe that they are part of invisible structures in the Sagittarius constellation of our own Milky Way. And they are whopping big. The swath of space that Earth cuts as it makes a one year transit around the Sun is about the scope of the structures’ expected size. The telescopes used in Australia are radio telescopes so even though these dark matter structures are invisible, the Australian array is able to detect their presence in the Sagittarius constellation by “seeing” the gravitational affect on nearby stars and detecting changes in radio wavelengths within light.

Now, we’re not talking about invisible extra-terrestrial shopping malls. Astronomers are positing that it is more likely that the structures are large clouds of gas. They describe their shape as noodle-like. The gringa thinks maybe these are the spaghettified remains of objects sucked through a black hole. Scientists believe they are hollow. However, there is also the possibility that they are flat and one dimensional, like a bed sheet and they are viewing the edge. The gringa says, “Who the heck knows?! That about sums it up.”

Whatever they are and however they came about are distinct mysteries. All scientists really know is that they exist. The structures were discovered in 2014 when light from quasar PKS 1939-315 passed through the structures and became distorted. The light itself was not distorted but, rather, the radio wavelength band. Because the light intensity was not affected, it is believed that the invisible structures are dark matter that contain no dust. Kind of like light passing through a drinking glass. If the glass is clean, the light passes through just as bright on exit as on entry but still distorted. If the glass is dusty, the brightness of the light passing through dims in addition to the distortion produced by the glass’ matter itself.

These structures are not just sitting there twiddling their thumbs. Scientists have estimated that they are traveling about 30 miles per second (or 50 kilometers per second). Seeing as how they are about 3,000 light years away, the gringa’s not afraid of a surreptitious impact with invisible “stuff”.

But do the scientists know if this missing stuff serves a purpose? It seems that everything else in nature has a purpose, its own vital part in the grand scheme of things. These invisible structures could be very important. The gringa thinks it’s great to study them but we may not want to go messing about and interfering. Who knows what the heck could happen!

It seems that there are multiple theories on what their purpose is. Some scientists believe that the structures don’t behave like un-structured dark matter. Dark matter does not follow rotational and orbit patterns and could serve a purpose like cosmic fibers that hold galaxies together. However, scientists are not so sure that once dark matter forms structures like this their cosmic fiber job is still what they are doing. The gringa wonders if maybe they are just big galactic recycle bins, containing left over bits of matter that are left over from the creation process stars go through.

Basically, scientists only know that they are there. Bing, bang, boom, and that’s it. It’s like saying, “Hey, a giant, invisible elephant lives in your house and we don’t know how he got there or why he stays and if he is doing anything that affects your life. But we just thought you would like to know that he’s there.” Yeah, thanks guys.

Sources:

www.yahoo.com

arxiv.org

www.narrabri.atnf.csiro.au

www.iflscience.com

Image Source: www.ottawa-rasc.ca