Brief introduction of YINGHUO-1 Micro-satellite for Mars environment

exploration

J. Wu, G. Zhu, H. Zhao, C. Wang, L. Lei, Y. Sun, W. Guo and S. HuangCenter for Space Science and Applied Research, CAS

Shanghai Astronomical Observatory, CAS

Yinghuo (YH) -- Name of the mission

China has long history of astronomical observation of

Mars, the very first observation record was made during

475-221BC.

The mission is named after the ancient Chinese name

for Mars “YingHuo”

Ying --- Red

Huo --- unpredictable

Yinghuo-1 (YH-1) mission

Fly opportunity with Phobos-Grunt

China and Russia signed the agreement in March

2007. The cooperation includes:

1) Piggy back launch of a Chinese Mars exploration

satellite YH-1 (~115kg)

2) Russia will provide ground TTC support to YH-1

3) Phobos-Grunt and YH-1 will carry out joint

measurements of Martian space environment

Fly opportunity with Phobos-Grunt

Overview of the spacecraftYH-1– 3 axis stabilized platform, with deployable solar panel– Mass: 110kg– Power: 90W (average) 180W (peak)– payload mass: 11 kg– payload power: 20 W – nominal life time: 1 year

Overview of the spacecraftYH-1 orbit parameters：

apogee ~80,000 km perigee 800 km inclination 36

800km 80000kmOrbit of Phobos

Scientific objectives of YH-1

This orbit will well cover the areas of solar wind, bow shock, magnetosheath, magnetic pileup region, and tail and plasma sheet.

Nagy et al.,2004

Scientific Objectives

1 To study details of Martian space magnetosphere, ionosphere and the plasma distribution and their variations;

2 To study Martian ion escape mechanism, its implication for water loss.

3 To have moderate surveys of Martian surface topography, sandstorm and its influence on ionosphere;

4 To explore the Martian gravity field near equator by analyzing orbital data of YH-1.

Instruments Goals

Flux gate magnetometer Space magnetic field measurement

Plasm

a pack

age

Electron analyzer Measuring plasma distribution : energy, mass, velocity

two ion analyzers

Two frequency occultation receiver

Ionosphere occultation

Photo-imager Sandstorm and Mars surface imaging

Scientific payloads of YH-1

Magnetometer• Flux-gate magnetometer,

measures 3 components of magnetic field.

• 2 sensors– double redundant

– gradiometer to eliminate S/C remnance

Sensor A

Sensor B

Solar panel

YH-1 spacecraft

Parameter Specifications Dynamic range 256nT

Noise 0.01 nT/√Hz@ 1Hz Resolution 0.01 nT

(RMS in 10 Hz bandwidth) Mass

2 sensors Electronics

2800g 500g (+cable & connector) 2300g

Size Sensor Electronics

102.2×58×50 (mm) 270×210×58 (mm)

Power 6.0 W

Magnetometer

Plasma package• two identical ion analyzers• one electron analyzer• electronics

Plasma Package

Plasma package• Ion analyzer

– Electrostatic analyzer + TOF scheme,

to resolve ion mass/direction/energy

• Specifications– Field of view: 360160, 8 angular sectors in polar

direction

– Energy range: 20eV-15keV

– Energy resolution: 7%, 96 bins

– Mass resolution: 1, 2, 4, 8, 16, >32 amu

• 2 identical ion sensors simultaneous measurements – Better angular coverage and resolving ability

Plasma Package• Electron analyzer

– Electrostatic analyzer

– Electron direction/energy spectrum

• Specifications– Field of view: 9120 8 azimuth angular sectors

– Energy range: 20eV-15keV

– Energy resolution: 15%, 32 bins

Occultation Receiver– Sensitivity: ≤-145 dBW;– Measuring accuracy of carrier phases: 1/100

cycle(0.02m);– Sampling rate: 10Hz;– Antenna polarization: linear polarization;– Operating frequencies: 833MHz, 416.5MHz

• Receive signals at two frequencies from Phobos mission,

• Ionosphere Occultation between YH-1 and Phobos

• Focused on sub-solar and midnight ionosphere, never tapped by previous occultation due to limit of Sun-Earth-Mars geometry.

Occultation Receiver

Optical Imager CMOS Imaging Sensor

Specifications

Wide FOV cameraNarrow FOV

camera

Pixels ≥ 4 million ≥ 4 million

SNR ≥30dB ≥30dB

Power ＜ 3W ＜ 3W

Weight 1.3±0.1kg 1.3±0.1kg

Resolution global images@ 10,000km

≤0.5Km at Perigee

≤ 0.3Km at Perigee

SDRAM 10 full resolution image

5 full resolution image

Besides independent observation of the Martian environment, joint operations with Phobos mission are also planned:

1. Two-point measurements of the Mars space environment

2. S/C to S/S radio occultation measurements

3. Data archiving and exchange

Joint Operations

1. Two-point measurements of the Martian space environment

Joint Operations

Joint Operations

2. S/C to S/C radio occultation measurements

• Before/after FGSC landed on Phobos

Start time (UTCG) Off time （ UTCG）

duration

backup

1 2010 10.10 17:53 :55.81 2010 10.10 18:04:21.23 11min

2 2010 10.13 17:24:41.59 2010 10.13 17:40:36.29 16min

3 2010 10.16 16:56:04.51 2010 10.16 17:16:16.68 20min

4 2010 10.19 16:27:46.32 2010 10.19 16:51:40.91 24min

5 2010 10.22 15:59:39.01 2010 10.22 16:26:56.70 27min

6 2010 10.25 15:31:39.53 2010 10.25 15:35:37.82 4min

7 2010 10.25 15:58:09.98 2010 10.25 16:02:6.84 4min

8 2010 10.28 15:03:45.99 2010 10.28 15:07:23.06 4min

9 2010 10.28 15:33:36.76 2010 10.28 15:37:12.91 4min

10 2010 10.31 15:12:58.21 2010 10.31 15:15:27.38 3min

11 2010 11.21 12:15:22.00 2010 11.21 12:17:54.69 2.5min Eclipse

YH-1 and Phobos-Grunt are going to make

a series scientific break through in the area of

Mars space environment exploration.

We should get fully prepared for these

exciting events with good plans of joint

operation.

Summary

Thank You!Thank You!

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