The summer polar lower thermosphere (90–100 km) has an interesting connection to meteors, adjacent to the mesopause region attaining the lowest temperature in summer. Meteors supply condensation nuclei for charged ice particles causing polar mesospheric summer echoes (PMSE). We report the observation of meteor trail with nearly horizontal transit at high speed (20–50 km/s), and at last with re-enhanced echo power followed by diffusive echoes. Changes in phase difference between radar receivers aligned in meridional and zonal directions are used to determine variations in horizontal displacements and speeds with respect to time by taking advantage of radar interferometric analysis. The actual transit of echo target is observed along the straight pathway vertically and horizontally extended as much as a distance of at least 24 km and at most 29 km. The meteor trail initially has a signature similar to ‘head echoes’, with travel speeds from 20 – 50 km/s. It subsequently transforms into a different type of echo target including specular echo and then finally the power reenhanced. The reenhancement of echo power is followed by fume-like diffusive echoes, indicating sudden release of plasma as like explosive process probably involved. We discuss a possible role of meteor-triggered secondary plasma trail, such as fireball embedded with electrical discharge that continuously varies the power and transit speed.

1. INTRODUCTION
 2. DATA ANALYSIS
 3. RESULTS
  3.1 Features of Echo Power and Phase Structure
  3.2 Directional Movement of Meteor Trail
 4. DISCUSSION
  4.1 Comparison with Traditional Meteor Trails
  4.2 Interpretation of the Observed Meteor Echoes
 5. SUMMARY AND CONCLUSIONS
 ACKNOWLEDGMENTS
 REFERENCES

• Young-Sook Lee(Department of Astronomy and Space Science and Geology, Chungnam National University) Corresponding Author
• Sheila Kirkwood(Swedish Institute of Space Physics)
• Young-Sil Kwak(Korea Astronomy and Space Science Institute, Korea University of Science and Technology)