Space Debris

COSC 4335by

Arifur Sabeth11/30/2009

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

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.

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.

Objective

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

Pre-processing data

• Two types of Datasets are given

• Correlate them and visualize the effects of a new leakage.

• Possible future accidental loss.

Feature selection/ Dimensionality reduction

• Isolate NaK droplets from the 4014 objects in the 10-column table

• NaK droplets are supposed to be spherical in shape

• Find the high concentration in polarization of the NaK objects

• We can find concentration” or “clustering” in terms of their polarization, inclination, and altitudes.

Data mining

• By using WECA (software)

Post processing

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

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.

Question? Comments!

• Thank you.