Dynamics Explorer 1

The Dynamics Explorer (DE) mission's general objective is to
investigate the strong interactive processes coupling the hot,
tenuous, convecting plasmas of the magnetosphere and the
cooler, denser plasmas and gases corotating in the earth's
ionosphere, upper atmosphere, and plasmasphere. Two
satellites, DE 1 and DE 2, were launched together and were
placed in polar coplanar orbits, permitting simultaneous
measurements at high and low altitudes in the same field-line
region.

The DE 1 spacecraft (high-altitude mission) uses an
elliptical orbit selected to allow

* (1) measurements extending
from the hot magnetospheric plasma through the plasmasphere to
the cool ionosphere;
* (2) global auroral imaging, wave
measurements in the heart of the magnetosphere, and crossing
of auroral field lines at several earth radii; and
* (3) measurements for significant periods along a magnetic field
flux tube.

The spacecraft approximated a short polygon 137 cm
in diameter and 115 cm high. The antennas in the X-Y plane
measured 200-m tip-to-tip, and on the Z-axis are 9 meters tip-
to-tip. Two six-meter booms are provided for remote
measurements. Power is supplied by a solar cell array, mounted
on the side and end panels. The spacecraft is spin stabilized,
with the spin axis normal to the orbital plane, and the spin
rate at ten plus or minus 0.1 rpm. A pulse code modulation
(PCM) telemetry data system is used that operates in real time
or in a tape-recorder mode. Data have been acquired on a
science-problem-oriented basis, with closely coordinated
operations of the various instruments, both satellites, and
supportive experiments. Data acquired from the instruments are
temporarily stored on tape recorders before transmission at an
8:1 playback-to-record ratio. Additional operational
flexibility allows a playback-to-record ratio of 4:1. The
primary data rate is 16,384 bits per second. Since commands
are stored in a command memory unit, spacecraft operations are
not real time, except for the transmission of the wideband
analog data from the Plasma Wave Instrument (81-070A-02).

On October 22, 1990 science operations were terminated. On
February 28, 1991 Dynamics Explorer 1 operations were
offically terminated.

Additional details may be found in R. A.
Hoffman et al., Space Sci. Instrum., v. 5, n. 4, p. 349, 1981.

《动力学探索者》（DE）任务之总体目标在于探究耦合地球磁层中炽热、稀薄、对流等离子体与地球电离层、高层大气以及等离子体层中冷却、致密等离子体和气体的强相互作用过程。DE 1 和 DE 2 两颗卫星协同发射，并置于极地共面轨道，使得在同一磁力线区域内可实现高空与低空的同时测量。

DE 1 航天器（高空任务）采用椭圆形轨道，旨在实现以下目标：

* （1）从热磁层等离子体测量至等离子体层再到冷电离层的全范围测量；
* （2）全球极光成像、磁层中心的波动测量以及数个地球半径范围内的极光场线穿越；
* （3）沿磁通量管进行长时间的测量。

该航天器近似为一个直径 137 厘米、高 115 厘米的短多边形。X-Y 平面的天线长度为 200 米，Z 轴上的天线长度为 9 米。提供两个六米长的桅杆进行远程测量。电源由太阳能电池阵列提供，安装在侧面和端面板上。航天器采用自旋稳定，自旋轴垂直于轨道平面，自旋速度为每分钟十次加减 0.1 次。采用脉冲编码调制（PCM）遥测数据系统，可在实时或磁带记录模式中运行。数据以科学问题为导向进行采集，各种仪器、两颗卫星以及支持性实验的紧密协调运作。从仪器获取的数据在传输前临时存储在磁带记录器中，以 8:1 的放音至录音比进行传输。额外的操作灵活性允许 4:1 的放音至录音比。主数据速率为每秒 16,384 比特。由于指令存储在指令存储单元中，航天器操作并非实时，除从等离子体波仪器（81-070A-02）传输宽带模拟数据外。

1990 年 10 月 22 日，科学操作终止。1991 年 2 月 28 日，动力学探索者 1 的操作正式终止。

更详细的信息可参考 R. A. Hoffman 等人发表在《空间科学仪器》（Space Sci. Instrum.）第 5 卷第 4 期第 349 页的文章。