US

STUDY: Dramatic Uptick In Cosmic Rays From Deep Space Pose Big Risks For Earthlings

No featured image available

Radioactive cosmic rays from deep space are intensifying faster than previously thought and posing a greater threat to astronauts, according to a Space Weather study published in February.

Dramatic increases in powerful rays coming from the cosmos are placing astronauts at greater peril, the study notes. The uptick is curtailing how long they could safely travel through space. Astronauts’ depend on a protective barrier that’s actually losing some of its impact and worsening the threat.

The sun’s magnetic field and solar wind create a type of protective shied fending off the cosmic rays that enter the solar system. There’s only one problem — the sun’s shield is weakening, according to the study’s authors.

“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,” University of New Hampshire Professor Nathan Schwadron wrote in the study. The sun’s defensive mechanism is strongest during Solar Maximum and weakest during Solar Minimum.

“As a result of this remarkably weak solar activity, we have also observed the highest fluxes of cosmic rays,” he said of the Galactic cosmic rays, which are an ad-mixture of high-energy photons and sub-atomic particles that jettison toward Earth through supernova explosions in deep space.

Schwadron and his colleagues analyzed data from the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) instrument aboard NASA’s Lunar Reconnaissance Orbiter (LRO) to determine cosmic rays in the Earth-Moon system were peaking at record levels. The sun is not Earth’s only line of defense.

There have been at least 28 solar cycles since the latter part of the 17^th century. The current solar cycle began in January 2008 and exhibited minimal activity until early 2010. The most recent cycle lasted 11.6 years, beginning in May 1996 and ending in January 2008. The cosmic rays’ intensity has increased dramatically during that time.

Galactic radiation presents a more significant challenge: the time to three percent risk of exposure-induced death, or REID, in space was less than 400 days for a 30-year-old male during the last cycle 23–24 minimum, which is about 20 percent lower in the coming cycle 24–25 minimum. The amount of time an astronaut can stay in the cosmos is receding.

Many astronauts have spent up to 500 or more days in space. American astronaut Peggy Whitson set a galactic record in 2017 via being in space 535 days. Whitson broke the previous NASA record of 534 days in orbit over an astronaut’s entire career. She extended her stay on the International Space Station (ISS) by three months.

NASA has not launched an astronaut into space without the help of the Russians for the last five years, forcing the U.S. to pay Russia $71 million dollars per astronaut lifted to the ISS. Russia has repeatedly threatened to block American access to the $150 billion station in response to U.S. sanctions. America paid for 84 percent of the costs associated with building the ISS.

The rays also pose a threat to an astronaut’s loved ones on planet Earth. The planet’s magnetic field and atmosphere, taken together, mitigate some of the effect from cosmic rays. The rays’ growing intensity is having an effect, according to the study.

Earth to Sky Calculus students launched balloons with sensors that show a 13 percent increase in radiation (X-rays and gamma-rays) penetrating Earth’s atmosphere. The increase in radiation can have a dangerous effect on airline passengers and pilots, most of whom the International Commission on Radiological Protection classify as occupational radiation workers.

Follow Chris White on Facebook and Twitter.