A lesson and Learn from F3/C ionospheric A lesson and Learn from F3/C ionospheric

Observations for F7/C2Observations for F7/C2

2011.04.13

Tiger J. Y. LiuNational Space Organization

National Central University

1

Content

• Introduction

• Space-Space Tomography- 2D TIP+GOX Tomography- 2D TIP+GOX Tomography

- 3D TIP+GOX Tomography

- 2D TIP Tomography

• GOX N(500 km) vs. N(800)

• Conclusion

2

Error of Abel Inversion

Liu et al. (JGR 2010)3

Space-Space Ionosphere Tomography

[Hsu et al., T.A.O. 2009]4

Space-Space Tomography

TIP + TriG Tomography

5

TIP and 3 GOX inversionResult

Tomography

6

2000 40003000

5000 6000 7000

Hei

gh

t(k

m)

IRI

Result

8000 9000 10000

Hei

gh

t(k

m)

Electric density(#/cm3)7 7

Space-Space Tomography

TIP + TriG 3D Tomography

8

Grid :

Longitude <5°°°°> , Latitude <5°°°°> ,

Altitude<25km>

Result: IRI (2008-74-06)

3D tomography simulated

Initial Guess : uniform 1000 electron density (#/cm3)

Occultation Case :

2008-91~2008-93

COSMIC GOX data

(4500)

Nadir Sounding:

2008-91~2008-93

COSMIC orbit data

Height:0-800km

Sampling Rate:1min

(480km)9

300kmSpace-space

Tomography

IRI

10

120 E°Space-space

Tomography

IRI

11

Error of Tomography & Abel Inversion

Space-Space

Tomography

ABEL Inversion

Use Occultation

and Nadir

Sounding data for

tomography

Use Occultation inverted

electron density profile

12

150km 200km 250kmSpace-space

Tomography

Electron Density of Bird View

IRI

ABEL

Inversion

1313

150km 200km 250km

Space-Space

Tomography

Error Percentage of Bird View

ABEL

Inversion

14

300km 350km 400km

Space-space

Tomography

IRI

Electron Density of Bird View

IRI

ABEL

Inversion

15

300km 350km 400km

Space-Space

Tomography

Error Percentage of Bird View

ABEL

Inversion

16

20 E° 100 E° 180 E°

Space-space

Tomography

Electron Density of Side View

17

IRI

ABEL

Inversion

17

20 E° 100 E° 180 E°

Space-Space

Tomography

Error Percentage of Side View

ABEL

Inversion

18

Remark (1)

• The GOX and TIP observations provide the

vertical distribution and horizontal gradient

of the electron density, respectively.

• The space-space tomography yields a better • The space-space tomography yields a better

performance, which can be use to derive 3D

structure and dynamics of the ionospheric

electron density.

• A nadir sounder is essential for the F7

mission.

Space-Space Tomography

2D TIP Tomography

OSSE of 2-D Photometer Tomography on Science Payload F7/C2

Experiment Setup

• Use IRI to simulate the ionosphere

• Satellite (800km altitude, polar orbit)

• Photometer Sounding (1 Hz sampling rate,

135.6nm)

- 1 nadir photometer (F3/C TIP)

- 1 nadir and +45°°°° photometers

- 1 nadir, +45°°°°, and -45°°°° photometers

• Apply MART conducting the

Inversion/tomography (horizontal x vertical

resolution: 40kmx20km)

• Conclusion

IRI SimulationA

ltit

ude

el/cm3

Alt

itude

(km

)

Range (km)

Initial Guess (NmF2:10000#/cm3, hmF2:

250km)

1 nadir PhotometerA

ltit

ude

(km

)

el/cm3

Alt

itude

(km

)

Range (km)

1 nadir Photometer (i.e.TIP)

ObservationA

ltit

ude

(km

)

el/cm3

Alt

itude

(km

)

Range (km)

Inversion of 1 nadir PhotometerA

ltit

ude

(km

)

el/cm3

Alt

itude

(km

)

Range (km)

IRI

Alt

itude

(km

)

IRI vs. 1 nadir Photometer Inversion

1 nadir Inversion

Alt

itude

(km

)

Range (km)

el/cm3

1 nadir & +45 Photometer

ObservationA

ltit

ude

(km

)

el/cm3

Alt

itude

(km

)

Range (km)

1 nadir & + 45 Photometer Tomography A

ltit

ude

(km

)

el/cm3

Alt

itude

(km

)

Range (km)

IRI

Alt

itude

(km

)

el/cm3

IRI vs. 1 nadir & +45 Photometer Tomography

1 nadir & +45 Photometer TomographyAlt

itude

(km

)

Range (km)

el/cm3

Alt

itude

el/cm3

1 nadir & +/- 45 Photometer

ObservationA

ltit

ude

(km

)

Range (km)

Alt

itude

el/cm3

1 nadir & +/- 45 Photometer Tomography A

ltit

ude

(km

)

Range (km)

IRI

Alt

itude

(km

)

el/cm3

IRI vs. 1 nadir & +/- 45 Photometer Tomography

Alt

itude

(km

)

Range (km)

el/cm3

1 nadir & +/- 45 Photometer Tomography

Remark (2)

• The multi-photometer observation can be used

to reconstruct the height-latitude 2-D

ionosphere.

• The observation with nadir, +45°°°°, and -45°°°°• The observation with nadir, +45°°°°, and -45°°°°

photometers yields a batter tomography result.

• Time: 2007.061 ~ 2007.120

• UT: 12:00 ~ 14:00

• Longitude : -180 ~ 180• Longitude : -180 ~ 180

• Latitude : -60 ~ 60

• Altitude : 0 ~ 800km

Satellite Altitude

Side ViewLongitude

-15° 0° 15° 30° 45°

F3/C Alt:500km

60°

F3/C Alt:800km

Difference

OSSE Alt:500km

OSSE Alt:800km

-15° 0° 15° 30° 45° 60°

Difference

Bird viewAltitude

F3/C Alt:500km

150km 200km 250km 300km 350km

F3/C Alt:800km

OSSE

Alt:500km

OSSE

Alt:800km

IRI

150km 200km 250km 300km 350km

IRI

Error

Alt:500km

Error

Alt:800km

Side ViewLongitude

-15° 0° 15° 30° 45°

F3/C Alt:500km

60°

F3/C Alt:800km

OSSE Alt:500km

OSSE Alt:800km

IRI

-15° 0° 15° 30° 45° 60°

Error Alt:500km

Error Alt:800km

Conclusion

• The F7/C2 TriG together with TriP shall

provides a better resolution and accuracy for

the ionospheric electron density probing. the ionospheric electron density probing.

• The electron densities derived by the F7/C2

GOX should be carefully investigated.

Thank You !Thank You !