1935 Explorer II, a 113,000 cubic foot helium balloon ascends to a reco while collecting atmosphe cosmic ray data. search Viking research rocket fired from the ton Sound near Jarvis Island in the Pacific osmic ray and pressure and temperature data. . Van Allen (The University of Iowa) reports the first high altitude mic-ray intensity and latitude variation of heavy nuclei in primary cosmic iation, from his “Rockoon” (balloon-launched rocket).
November 11, 1935 Explorer II , a 113,000 cubic foot helium
Jan 02, 2016
November 11, 1935 Explorer II , a 113,000 cubic foot helium balloon ascends to a record 22,066 m while collecting atmospheric and cosmic ray data. May 11, 1950 - PowerPoint PPT Presentation
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November 11, 1935 Explorer II, a 113,000 cubic foot helium balloon ascends to a record 22,066 m while collecting atmospheric and cosmic ray data.
May 11, 1950 A Naval Research Viking research rocket fired from the U.S.S. Norton Sound near Jarvis Island in the Pacific collects cosmic ray and pressure and temperature data.
1952-57 James A. Van Allen (The University of Iowa) reports the first high altitude survey of total
cosmic-ray intensity and latitude variation of heavy nuclei in primary cosmic
radiation, from his “Rockoon” (balloon-launched rocket).
July 31, 1961 NASA funds high-altitude balloon measurements of the proton and alpha-particle spectrum of primary cosmic radiation conducted by the University of Chicago above Uranium City, Saskatchewan, Canada.
July 1969 Apollo 11 astronauts trap cosmic ray particles on exposed aluminum foil, returned to earth for analysis of its elemental and isotopic composition. With no atmosphere or magnetic field of its own, the moon’s surface provides a constant bombardment of particles.
December 1972 Apollo 17’s lunar surface cosmic ray experiment measured the flux of low energy particles in space (foil detectors brought back to Earth for analysis..
October 26, 1973 IMP-8 launched. Continues today measuring cosmic rays, Earth’s magnetic field, and the near-Earth solar wind from a near-circular, 12-day orbit (half the distance to the moon).
October 1975 to the present GOES (Geostationary Orbiting Environmental Satellite) An early warning system which monitors the Sun's surface for flares.
1977 The Voyager 1 and 2 spacecraft are launched. Each will explore acceleration processes of charged particles to cosmic ray energies.
July 1992 SAMPEX (Solar Anomalous and Magnetospheric Particle Explorer) into polar orbit. By sampling interplanetary and magnetospheric particles, contributes to our understanding of nucleosynthesis and the acceleration of charged particles.
July 1992 IMAX (Isotope Matter-Antimatter eXperiment) balloon- borne superconducting magnetic spectrometer measured the galactic cosmic ray abundances of protons, anti-protons, hydrogen, and helium isotopes.
August 25, 1997 Advanced Composition Explorer (ACE) was launched!
Hydrogen (H) 1 1.00 640
Helium (He) 2 6.8 10-2 94
Lithium, beryllium, boron 2.6 10-9 1.5
Carbon, Nitrogen, Oxygen 1.2 10-3 6
Iron (Fe) 26 3.4 10-5 0.24
All heavier atoms 1.9 10-6 0.13
ElementAtomic
Number (Z)
Solar SystemComposition
(relative number of atoms)
PrimaryCosmic Ray
Flux(particles/m-2 sec)
50m
Cosmic ray strikes a nucleuswithin a layer of
photographicemulsion
Primary cosmic ray
Mostly photons, electrons and muons at Earth’s surface
A 1019 eV Extensive Air Shower
100 billion particles
at sea level
89% photons10% electrons~1% muons
12 km
6 km6 km
The Cosmic Ray Energy Spectrum
(1 particle per m2-sec)
(1 particle per m2-year)
(1 particle per km2-year)
Cosmic Ray Flux
Energy (eV)
Refrigerator cold CO2 bubble (887 mph)
0.02 eV
Room temperature nitrogen N2 (1160 mph)
0.03 eV
Atoms in sun’s MILLION DEGREE surface0.50 eV
Energy given to each single electron whenaccelerated by AA battery 1.5 eV
Electrons accelerated by your televisionpicture tube (traveling ~1/3 speed of light)
30,000 eV
Fermi National Lab’s high energy protons 1,000,000,000,000 eV
Superball bounced over your house 4 x 1017 eV
Pitched baseball 4 x 1020 eV
Slammed hockey puck 1 x 1021 eV
Recall: 1 joule = 6.2 x 1018 eV
The highest energy Cosmic Rays areSUBATOMIC particles carrying theenergy of MACROSCOPIC objects!
4 x 1021 eV = 60 joules
The Cosmic Ray Energy Spectrum
FERMILAB’s protonsFERMILAB’s protons
Bounced Superball
Bounced Superball
Pitched baseballPitched baseball
Hockey PuckHockey Puck
Energy (eV)
Two possible sources of cosmic rays
Colliding galaxies
Active galacticnucleus
GZK Cutoff
1966 - K. Greisen - G.T.Zatsepin & V.A.Kuz’min
showed the recently discovered cosmic microwave background radiation (CMBR)effectively makes the universe opaque tosufficiently high energy cosmic particles.
GZK Cutoff
For example:
p *+0 p
++ n
and similar resonances yield attenuation lengths mere 10s of Mega parsecs for cosmic ray protons with E>1019 eV.
Center of (our) Virgo supercluster is approximately 20 Mpc away
All E>1019 eV primaries must originate within 100 Mpc of the earth
1966 - K. Greisen - G.T.Zatsepin & V.A.Kuz’min
p
Energy [eV]
ICRC2001 news
AGASA: 717
HiRes: 7 2
events above 1020eV
AGASA
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