以下资料说是:国际重力界期盼已久的GOCE卫星,要在这个月发射.由于等米(----GOCE获取的实际数据)下锅,众多研究者已经消磨了些许时光,处理GOCE获取的重力梯度(重力位的二阶导数)的软件已经有N种.

只要数据有了,相信会引发一个股论文潮.不会再总是以模拟数据进行模拟计算了,这样的结果才让人更兴奋.

实测数据将检验以下三个预期结果:

• 以毫伽 (1 mGal (1 mGal = 10^–5 ms^–2) ,ms^–2即米/秒的平方)的精度确定重力异常.
• 以1-2厘米的精度确定大地水准面.
• 实现100公里的空间分别率.

 

以下资料来自欧洲空间局网站

 

http://www.esa.int/esaLP/ESAYEK1VMOC_LPgoce_0.html

ESA's gravity mission GOCE

 

Planned for launch in March 2009, ESA's Gravity field and steady-state Ocean Circulation Explorer (GOCE) has been developed to bring about a whole new level of understanding of one of the Earth's most fundamental forces of nature – the gravity field.
 
Dubbed the 'Formula 1' of spacecrafts, this sleek high-tech gravity satellite embodies many firsts in terms of its design and use of new technology in space to map Earth's gravity field in unprecedented detail. As the most advanced gravity space mission to date, GOCE will realise a broad range of fascinating new possibilities for the fields of oceanography, solid Earth physics, geodesy and sea-level research, and significantly contribute to furthering our understanding of climate change.  
 
Although invisible, gravity is a complex force of nature that has an immeasurable impact on our everyday lives. It is often assumed that the force of gravity on the surface of the Earth has a constant value, but in fact the value of 'g' varies subtly from place to place. These variations are due to a number of factors such as the rotation of the Earth, the position of mountains and ocean trenches and variations in density of the Earth's interior.
 橙色部分大意:

尽管重力不可见,这种复杂的力,一直在(难以估量地)影响着我们的生活.人们常假定重力的数值恒定,其实它(以g表示)随空间的变化在奇妙地变化着,影响因素有地球的自转,山脉海沟的位置,以及地球内部密度的变化等.
 

	GOCE to map gravity as never before

Over its lifetime of about 20 months, GOCE will map these global variations in the gravity field with extreme detail and accuracy. This will result in a unique model of the geoid, which is the surface of equal gravitational potential defined by the gravity field – crucial for deriving accurate measurements of ocean circulation and sea-level change, both of which are affected by climate change. GOCE-derived data is also much needed to understand more about processes occurring inside the Earth and for use in practical applications such as surveying and levelling.
 
 

GOCE takes six simultaneous measurements of the gravity field

Since the gravitational signal is stronger closer to Earth, the 'arrow-like', five-metre long GOCE satellite has been designed to cut through of what remains of the Earth's atmosphere at just 250 km above the surface of the planet. This low-orbiting spacecraft is the first mission to employ the concept of gradiometry - the measurement of acceleration differences over short distances between an ensemble of proof masses inside the satellite.
 
 
GOCE is equipped with three pairs of ultra-sensitive accelerometers arranged in three dimensions that respond to tiny variations in the 'gravitational tug' of the Earth as it travels along its orbital path. Because of their different position in the gravitational field they all experience the gravitational acceleration of the Earth slightly differently. The three axes of the gradiometer allow the simultaneous measurement of six independent but complementary components of the gravity field.

Although the gradiometer forms the heart of the satellite, to measure gravity there can be no interference from moving parts so the entire spacecraft is actually one extremely sensitive measuring device.
 
 
Mission objectives

• to determine gravity-field anomalies with an accuracy of
  1 mGal (where 1 mGal = 10^–5 ms^–2).
• to determine the geoid with an accuracy of 1-2 cm.
• to achieve the above at a spatial resolution better than
  100 km.

 

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