NASA 2001 Mars Odyssey page 1 Workshop HEND - 2002 Russian Aviation and Space Agency Institute for Space Research Orbital variation of counts rate in anti-coincidence

Russian Aviation and Space AgencyInstitute for Space Research

NASA 2001 Mars Odyssey page 1

Workshop Workshop HENDHEND -- 20022002

Orbital variation of counts rate in Orbital variation of counts rate in anti-coincidence detector of anti-coincidence detector of

HENDHEND

WorkshopWorkshop““The First year of HEND operations on the NASA Odyssey Mars The First year of HEND operations on the NASA Odyssey Mars

Orbiter”Orbiter”Moscow, RussiaMay 20-22, 2002




Observations of anomalous signal in interplanetary spaceObservations of anomalous signal in interplanetary space

Time profiles for S4, S5 Time profiles for S4, S5 and soft channel S6 for and soft channel S6 for all June 2001all June 2001

CRUISECRUISE




Spectra and time profile for soft channel S6 in “quiet” and “anomalous” periodsSpectra and time profile for soft channel S6 in “quiet” and “anomalous” periods

area A on previous slide area A on previous slide area B on previous slidearea B on previous slide

2001 June 01 – 08 2001 June 01 – 08 2001 June 16 – 24 2001 June 16 – 24

CRUISECRUISE




Observations of anomalous signal near MarsObservations of anomalous signal near Mars

Time profiles for S4, S5 and Time profiles for S4, S5 and soft channel S6 for October soft channel S6 for October 24 – November 2924 – November 29

AEROBRAKINGAEROBRAKING




Time profiles for S4, S5 Time profiles for S4, S5 and soft channel S6 for and soft channel S6 for area (1) on previous area (1) on previous slide.slide.





Spectra for “quiet” period (A) and for “anomalous” ones (B)Spectra for “quiet” period (A) and for “anomalous” ones (B)

area A on previous slidearea A on previous slide area B on previous slide area B on previous slide

2001 October 24 – 25 2001 October 24 – 25 2001 October 25 – 262001 October 25 – 26





1. All counts of soft channels of 1. All counts of soft channels of S6 projects on belt mainly S6 projects on belt mainly between equator and 60between equator and 6000 degree degree in north hemisphere without any in north hemisphere without any correlation with topography.correlation with topography.

Variation of counts rate in Variation of counts rate in anti-coincidence detector anti-coincidence detector

during mapping have some during mapping have some peculiar features:peculiar features:

MAPPINGMAPPING

Map of gamma albedo of Mars.Map of gamma albedo of Mars.

(Data from 18 February to 16 May 2002)(Data from 18 February to 16 May 2002)




MAPPINGMAPPING

Typical time profiles for soft Typical time profiles for soft channel S6. channel S6. (Data for 11 March 2002)(Data for 11 March 2002)

Illumination of Odyssey by Sun. Illumination of Odyssey by Sun. (Solid angle of Mars minus Angle (Solid angle of Mars minus Angle (Sun,Mars) for 11 March 2002)(Sun,Mars) for 11 March 2002)

2. All time profile of 2. All time profile of anomalous signal have anomalous signal have similar structure: “day” similar structure: “day” and ” night” peaks.and ” night” peaks.




4. Spectra of “day” and “night” peaks have different form.4. Spectra of “day” and “night” peaks have different form.

MAPPINGMAPPING




2002 March 21-22, S6 [ch 1-5]

0

500

1000

1500

2000

2500

3000

14:0

7:2

0

15:1

5:3

6

16:0

2:3

2

17:1

5:0

4

17:5

9:4

7

21:1

2:5

8

22:0

0:5

4

23:0

9:1

0

23:5

6:0

6

1:1

5:0

2

1:5

3:2

6

3:1

8:4

5

3:5

5:0

1

5:1

3:5

7

5:5

0:1

3

9:0

6:2

9

9:4

9:0

9

11:0

5:5

7

13:0

5:2

4

13:4

3:4

8

14:5

8:2

8

15:3

6:5

2

16:5

7:5

5

17:3

6:1

9

19:4

8:3

5

21:4

1:3

9

Time

Du

rati

on

(s

ec

)

Day

Night

Day(mean)

Night (mean)

MAPPINGMAPPING

3. All “day” peaks 3. All “day” peaks are shorter then are shorter then “night” ones.“night” ones.

2002 April 13, S6 [ch1-5]

0

500

1000

1500

2000

2500

3000

0:3

6:2

0

1:2

8:2

2

2:3

8:0

7

3:2

4:3

9

4:3

6:5

5

5:2

5:3

1

6:3

4:1

2

7:2

3:2

0

8:3

3:0

0

9:1

9:3

7

10:3

1:4

9

11:1

4:2

3

12:2

9:0

6

13:1

5:1

5

14:2

7:5

4

15:1

9:1

1

16:2

6:4

2

17:1

7:0

0

18:2

2:2

8

19:1

0:4

1

20:1

2:0

8

21:1

4:1

0

22:2

1:3

6

23:1

3:3

1

Time

Du

rati

on

of

peak (

sec)

Day

Night

Day (mean)

Night (mean)

Duration of “day” and Duration of “day” and ”night” peaks. ”night” peaks. (Data for typical (Data for typical days of March and April 2002)days of March and April 2002)



Workshop Workshop HENDHEND -- 20022002MODELMODEL




RedRed and and blueblue parts of circular orbit parts of circular orbit of spacecraft are time intervals of spacecraft are time intervals where “day” and “night” peaks of where “day” and “night” peaks of anomalous signal in soft channel of anomalous signal in soft channel of

anticoincidence detector observedanticoincidence detector observed..

MODELMODEL

Documents

NASA 2001 Mars Odyssey page 1 Workshop HEND - 2002 Russian Aviation and Space Agency Institute for Space Research Orbital variation of counts rate in anti-coincidence