Cosmic Rays: Explaining the Universe's High-Energy Particles

High-energy astrophysics studies cosmic phenomena through gamma-ray and X-ray observations, using specialized instruments like Cherenkov telescopes (HESS, MAGIC, VERITAS) and space-based observatories (Fermi). Key sources include pulsar wind nebulae, supernova remnants, binary star systems, and the galactic center, while gamma-ray bursts represent the most energetic events in the universe, releasing energy equivalent to 100 solar masses in seconds. The field is rapidly developing with new observatories like LHAASO and CTA expanding our understanding of cosmic accelerators.

The universe hosts increasingly powerful phenomena that Ice Cube aims to study. Supernovae mark the deaths of massive stars that collapse under their own gravity and explode, releasing energy and creating heavy elements. More powerful are gamma ray bursts, produced when two neutron stars collide or through hypernovae—supernovae of stars 100 times more massive than the Sun that collapse into black holes. At the center of galaxies lie supermassive black holes (AGN) whose extreme gravity accelerates matter to produce particles with energies exceeding Earth's largest particle accelerators. These objects generate tremendous jets of particles, and Ice Cube searches for the high-energy neutrinos these processes emit, hoping to answer fundamental questions about their formation mechanisms.

Astronomers have proposed a unified model explaining hyper-luminous supernovae (which shine 10-100 billion times brighter than typical supernovae) and long-duration gamma-ray bursts as originating from the same source: a neutron star with a small misalignment between its rotation axis and magnetic axis. In this model, substantial fractions of the star's rotational energy simultaneously fuel the supernova explosion and power the relativistic particle jets that produce the gamma-ray burst, providing a single explanation for two previously separate high-energy cosmic phenomena.

Gamma ray bursts (GRBs) are among the most energetic events in the universe, originating from collapsing stars. The video describes GRB190114C, observed 5 billion light years away, which emitted photons at 1 terra electron volt (TEV), equal to 1 trillion volts—1 trillion times more energy per photon than visible light. This extreme energy requires material to be emitted at 99.999% the speed of light and forced through surrounding gas at light speed. Such observations challenge physicists' understanding of matter behavior at relativistic speeds and represent breakthroughs in astrophysics research.

This comprehensive segment covers the most violent and spectacular events in the universe. Novae are sudden brightness outbursts in binary star systems where a white dwarf draws matter from a companion star until it reaches the Chandrasekhar limit, triggering thermonuclear reactions. Supernovae are far more violent, occurring when massive stars (at least 8 times the Sun's mass) collapse at the end of their lives. The segment explores T Coronae Borealis, a binary system 3,000 light-years away that will produce a visible Nova this year. It also examines Betelgeuse, a red supergiant 700-1,000 times larger than our Sun, and Canis Majoris, one of the most massive stars in our galaxy. The segment covers gamma-ray bursts—brief flashes of gamma radiation classified as long or short bursts—and the revolutionary discovery of kilonovae, which result from colliding neutron stars and release 1,000 times more energy than normal Novae. Kilonovae are believed to be the primary mechanism for creating heavy elements like gold and platinum in the universe.

Cosmic ray showers are cascades of secondary particles (electrons, protons, and photons) produced when high-energy primary cosmic rays interact with atmospheric atomic nuclei; the cascade continues through alternating production of electron-positron pairs and proton production until the particle energy falls below a critical threshold, creating a self-sustaining chain reaction that dissipates the original cosmic ray's energy throughout the atmosphere.

When high-energy cosmic ray particles enter Earth's atmosphere, they collide with atmospheric nuclei and produce cascades of secondary particles called air showers. These showers spread across areas several kilometers wide. Since direct cosmic ray detection is impossible due to Earth's magnetic field deflecting charged particles, scientists observe these secondary particles instead. The Pierre Auger Observatory uses over 1,500 water tanks spread across 3,000 square kilometers to detect these cascades and infer properties of the original cosmic rays.

When cosmic ray particles enter Earth's upper atmosphere (between 25-40 km altitude), they collide violently with atmospheric molecules. The colossal energy contained in these particles is converted into mass, immediately producing cascades of secondary particles. These secondary particles then disintegrate and break apart the nuclei of adjacent atoms, creating step-by-step particle showers through a microscopic game of billiards unfolding on incredibly small timescales.

When high-energy cosmic ray particles collide with atmospheric atoms, they produce air showers—sprays of thousands or millions of secondary particles. The initial collision energy is converted into new particles through hadronization, where quarks are ripped apart and generate partner quarks from nothing. Higher energy collisions produce heavier particles like muons and strange quarks. Pair production can also occur, converting light into particle-antiparticle pairs. This demonstrates matter-energy interconversion.

An air shower is an extensive cascade of ionized particles and electromagnetic radiation produced when a primary cosmic ray enters Earth's atmosphere, creating a chain reaction where unstable hadrons decay into secondary particles including muons, neutrons, electrons, protons, antiprotons, alpha particles, pions, electrons, positrons, and neutrons; these showers were discovered by Bruno Rossi in 1934 through simultaneous particle detection at multiple sites, and can be detected using surface detectors (Cherenkov and scintillation counters), optical telescopes measuring fluorescence and Cherenkov light, and radio antennas that detect emissions from electron-positron deflection by Earth's magnetic field.

Cosmic rays—high-energy particles from supernovae and solar flares—constantly bombard Earth's atmosphere. While harmless to humans on the ground, these particles cause Single Event Upsets (SEUs) in electronic devices by creating free charges in sensitive circuits. At altitudes above 9 kilometers, radiation intensity increases 300-fold. Documented aviation incidents, including a 2008 Qantas crash where 110 passengers were injured, demonstrate real risks. Error rates vary by device: routers with 25GB memory experience errors every 17 hours, while laptops at cruising altitude fail every 5 hours. As electronics become more powerful and ubiquitous, cosmic radiation poses growing challenges for aviation safety and electronic reliability.

Cosmic rays pose significant risks to aviation and space systems. At cruising altitude, cosmic ray radiation increases from 0.5 to 1 microSievert per hour, and over 3 microSieverts near the poles, increasing single event upset chances by 10-30 times. On October 15, 1991, an A330 aircraft experienced a sudden pitch-down, diving 200 meters in 20 seconds. The investigation found the fault occurred with the air data inertial reference unit, with a single event effect from a high-energy atmospheric particle striking an integrated circuit. The space shuttle was designed with redundancy, using four computers running identical software. If one computer had a soft error, the other three would overrule it. On one 5-day mission (STS-48), there were 161 separate bit flips detected.

This section examines cosmic ray effects across technological domains. Cosmic rays create particle showers when primary rays collide with atmospheric molecules 25 km above Earth. IBM estimates one bit change per 256 MB RAM monthly from neutron-induced errors. In 2008, Qantas Flight 72 experienced a 200-meter dive when cosmic rays caused ADIRU bit errors, misidentifying altitude as angle of attack. Radiation increases with altitude: 0.5 μSv/h at 5,500m, exceeding 3 μSv/h at 10,000m. Spacecraft employ radiation-hardened electronics and quadruple-redundant systems. The Perseverance rover uses PowerPC processors designed for 40x more radiation tolerance. Throughout Earth's history, cosmic rays may have contributed genetic mutations for natural selection, demonstrating their pervasive influence on both technology and biology.

Cosmic rays are high-energy subatomic particles, mostly protons, traveling at nearly the speed of light, created by supernovae (the explosive deaths of massive stars eight times more massive than our sun); these particles can travel millions of light-years across the galaxy and occasionally penetrate aircraft computer systems at altitudes above 30,000 feet, potentially causing unexplained mid-air emergencies like the JetBlue flight incident where a sudden 100-foot drop injured 15 passengers due to cosmic ray-induced electronic failures.

Cosmic rays—high-energy particles from distant supernova explosions—can penetrate aircraft electronics and cause single-event upsets (SEUs) that flip bits in binary computer systems, potentially triggering dangerous malfunctions like sudden altitude loss, as demonstrated by the 2025 JetBlue incident where an Airbus A320 lost altitude over Florida without any mechanical failure, forcing an emergency landing and leading to the grounding of over 6,000 Airbus aircraft worldwide.