Space Debris

1. Space Debris COSC 4335 by ArifurSabeth 11/30/2009

2. Introduction • Space debris, also known as orbital debris, space junk • First satellite was launch in 1957 and break up in 1961. • sodium-potassium (NaK)is one of the most important non-fragmentation sources of space debris

3. Travelling speed • In low Earth orbit (below 2,000 km), orbital debris circle the Earth at speeds of 7 to 8 km/s. However, the average impact speed of orbital debris with another space object will be approximately 10 km/s.

4. Effects • Debris left in orbits approximately 600 km normally fall back to Earth within several years. • At altitudes of 800 km, the time for orbital decay is often measured in decades. • Above 1,000 km, orbital debris will normally continue circling the Earth for a century or more.

5. Objective • The objective of this paper is to find the effect of the NaK droplets on the long term evolution around the earth.

6. Pre-processing data • Two types of Datasets are given • Correlate them and visualize the effects of a new leakage. • Possible future accidental loss.

7. Feature selection/Dimensionality reduction • Isolate NaK droplets from the 4014 objects in the 10-column table • NaKdroplets are supposed to be spherical in shape • Find the high concentration in polarization of the NaKobjects • We can find concentration” or “clustering” in terms of their polarization, inclination, and altitudes.

8. Data mining • By using WECA (software)

9. Post processing • After using the Data mining algorithm we reduces the number of data from 4143 rows to 66 rows.

10. Results • Sodium potassium coolant droplets (NaK) ~ 1 mm to 5 cm • The effects of a new leakage at the low altitude of Cosmos 1900 would be significant.

11. Question? Comments! • Thank you.