Aerospace EnvironmentASEN-5335

• Instructor: Prof. Xinlin Li (pronounce: Shinlyn Lee)

• Contact info: e-mail: lix@lasp.colorado.edu (preferred)

phone: 2-3514, or 5-0523, fax: 2-6444,

website: http://lasp.colorado.edu/~lix

• Office hours: 9:00-11:00 pm Wed at ECOT 534, Tue & Thu, after class.

• Read Chapter 1 & 2.

Energetic electrons and protons are not able to penetrate down to the Earth’s

surface directly. Particles gain entry through the cusps that are shaped like

funnels over the polar regions or they enter far downstream from the Earth.

Particles that enter downstream can be transported toward the Earth and

accelerated to high energies, producing auroras and radiation belts.

The Earth’s Magnetosphere

The flare was an ‘X-class’ and accompanied by one of the largestsolar energetic proton events ever recorded

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These protons reach Earth inless than 30 minutes

Less than 1 hour afterthe initial proton arrivalthe POLAR/VIS imageris saturated and remainsso for almost a day

Vis-proton-bastille

A Schematic View of the Locations of Radiation Belts

• Blue: inner belt, >100MeV protons, rather stable

• Purple: outer belt, 100s keV and MeV electrons and ions, not stable at all

• Slot region in between

• Yellow: ACRs, stable

• White line: Earth’s magnetic field, approx. by a dipole field

Charged Particle Motions in Earth’s Magnetic Field

• Gyromotion motion: =p2/2mB (1st), T_g~10-3 sec

• Bounce Motion: J= p||ds (2nd), T_b~100 sec • Drift motion: =BdA (3th) , T_d~103 sec

PARTICLE ENERGIES OF CONCERN

EVA

• EVAs - additional radiation exposure concern– Lower shielding– Eye dose– Skin dose

• 51.6 degrees, new concern for electron events– One area where we don’t currently have a good model. Have

limited measurements outside at our orbits during events from Shuttle and MIR, so we don’t have enough data for any kind of empirical model.

• 145 more EVAs are planned for ISS completion

The flare was an ‘X-class’ and accompanied by one of the largestsolar energetic proton events ever recorded

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ISS ALTITUDE PROFILEInternational Space Station As Flown Altitude Profile

(Based on MCC-M/USSP Tracked SV Data)

320.0322.5325.0327.5330.0332.5335.0337.5340.0342.5345.0347.5350.0352.5355.0357.5360.0362.5365.0367.5370.0372.5375.0377.5380.0382.5385.0387.5390.0392.5395.0397.5400.0402.5405.0407.5410.0412.5415.0417.5420.0

11/17/98 01/16/99 03/17/99 05/16/99 07/15/99 09/13/99 11/12/99 01/11/00 03/11/00 05/10/00 07/09/00 09/07/00 11/06/00 01/05/01 03/06/01 05/05/01

Inv

aria

nt

Alt

. (km

) -

Ha,

Hp

, Hav

e

172.8174.1175.5176.8178.2179.5180.9182.2183.6184.9186.3187.6189.0190.3191.7193.0194.4195.7197.1198.4199.8201.1202.5203.8205.2206.5207.9209.2210.6211.9213.3214.6216.0217.3218.7220.0221.4222.7224.1225.4226.8

Inva

ria

nt

Alt

. (n

m)

ISS-2A1 (STS-096) Mated Reboost

ISS-2A.1 Reboost

ISS-2A2A (STS-101) Mated Reboost

ISS-1R (SM)- Rend Burns

ISS-1P (P251)- Test Burn

ISS-2A2B (STS-106) Mated Reboost

ISS-2A1 DAM

ISS-2A2B DAM

ISS-2A (STS-088) - Mated Reboost ISS-2A Test Burns

ISS-1AR Insertion

Burns

ISS-3A (STS-92) Mated Reboost

ISS-5A (STS-098) DAM

Mated Reboost

ISS-5A.1 (STS-102)

Mated Reboost

ISS-5A.1 3P Test

3P Reboost3P Phase

LEO GEO

Earth’s Debris Environment• Ground based radar and optical map > 1 cm below 2000 km

and > 10 cm above 2000 km• Shuttle surface and window damage for LEO• Need for smaller debris (<10 cm) map in most of space

National Space Weather Program To Advance

• observing capabilities• fundamental understanding of processes• data processing and analysis• numerical modeling transition of research into

operational techniques and algorithms• forecasting accuracy and reliability• space weather products and services• education on space weather 

National Space Weather Program

To prevent or mitigate• under- or over-design of technical systems• regional blackouts of power utilities• early demise of multi-million dollar satellites • disruption of communications via satellite, HF, and

VHF radio• disruption of long-line telecommunications• errors in navigation systems• excessive radiation doses dangerous to human health