Skip to main content
SearchLoginLogin or Signup

Potential for Airburst Detection on Titan with Dragonfly

Presentation #204.01 in the session Titan II: Atmospheres (Poster + Lightning Talk)

Published onOct 23, 2023
Potential for Airburst Detection on Titan with Dragonfly

Small meteors enter Titan’s atmosphere at an unknown rate. There have been no observations of such meteors, but it may be possible to detect them using ground-based assets such as NASA’s upcoming Dragonfly mission. Sufficiently strong or large meteors may result in an airburst, rather than gradually ablating away. Airbursts occur when an incoming meteor experiences a ram pressure from air drag that exceeds the dynamic strength of the meteor. This results in an explosive transfer of energy to the atmosphere and generates a shock wave that can be detected large distances away. NASA’s Dragonfly mission is equipped with both pressure sensors and a seismometer that may record meteors entering Titan’s atmosphere that result in an airburst.

To determine whether Dragonfly would be capable of detecting airbursts, we simulated a range of meteors 1 to 5 m in size entering Titan’s atmosphere. We used the fragment cloud model (FCM) to estimate burst height and energy release (Wheeler et al., 2017). Overpressures on the ground were then estimated by scaling the results of nuclear tests in Earth’s atmosphere (Glasstone and Dolan, 1977) to the energies and atmospheric conditions relevant on Titan. The meteors were assumed to be icy bodies with a density of 250 – 750 kg/m3 and internal strength varying from 0.1 to 1000 Pa. We found that the overpressure generated at Titan’s surface ranged from 10 – 15 Pa directly beneath the airburst. Stronger meteors result in a lower airburst height and larger overpressure at the surface. We also calculated the overpressures assuming the meteor would burst when the ram pressure exceeded the internal strength of the meteor body independent of fragmentation and ablation. This method resulted in slightly lower burst heights on average, with overpressure ranges of 14 – 45 Pa. To be detected by Dragonfly’s DraGMet instrument, the pressure sensors would need a sensitivity lower than 10 Pa for signals of short duration.

In the future, these overpressures can be used to simulate the distinct W-shaped vertical displacement profiles that may be detected by Dragonfly’s seismometer. Using both pressure sensors and the seismometer will increase the likelihood of detecting such an event.

Comments
0
comment
No comments here