Is each day is really shorter?

Dear Control Engineering: I heard something about the recent earthquake in Chile affecting the earth’s rotation. What’s that about?

03/06/2010


Dear Control Engineering: I heard something about the recent earthquake in Chile affecting the earth’s rotation. What’s that about?As strange as it sounds, NASA believes that the movement of the tectonic plates of the earth that caused the earthquake in Chile on February 27 has shifted the position of the earth’s axis and its rotation has speeded up. The Jet Propulsion Laboratory has reported that its calculations suggest that the earth’s figure axis, which is the axis on which our planet’s mass balances, shifted by about 3 inches during the earthquake. With that shift, the earth’s diameter has actually gotten smaller. This change has caused the earth’s rotation to speed up causing a day to be slightly shorter. The emphasis is on slightly, since the difference is a whopping 1.26 microseconds.

The JPL came to a similar conclusion after the big earthquake in Sumatra in 2004. Most of the news surrounding that quake was about the resulting Tsunami, but it was caused by a massive shift on the sea floor. The change in a day’s length was much more dramatic following that event at 2.68 microseconds. Such changes can’t really be measured, but they can be calculated.

So, feel free to leave work early.

Posted by Ask Control Engineering on March 6, 2010



No comments
The Engineers' Choice Awards highlight some of the best new control, instrumentation and automation products as chosen by...
The System Integrator Giants program lists the top 100 system integrators among companies listed in CFE Media's Global System Integrator Database.
The Engineering Leaders Under 40 program identifies and gives recognition to young engineers who...
This eGuide illustrates solutions, applications and benefits of machine vision systems.
Learn how to increase device reliability in harsh environments and decrease unplanned system downtime.
This eGuide contains a series of articles and videos that considers theoretical and practical; immediate needs and a look into the future.
Sensor-to-cloud interoperability; PID and digital control efficiency; Alarm management system design; Automotive industry advances
Make Big Data and Industrial Internet of Things work for you, 2017 Engineers' Choice Finalists, Avoid control design pitfalls, Managing IIoT processes
Engineering Leaders Under 40; System integration improving packaging operation; Process sensing; PID velocity; Cybersecurity and functional safety
This article collection contains several articles on the Industrial Internet of Things (IIoT) and how it is transforming manufacturing.

Find and connect with the most suitable service provider for your unique application. Start searching the Global System Integrator Database Now!

SCADA at the junction, Managing risk through maintenance, Moving at the speed of data
Flexible offshore fire protection; Big Data's impact on operations; Bridging the skills gap; Identifying security risks
The digital oilfield: Utilizing Big Data can yield big savings; Virtualization a real solution; Tracking SIS performance
click me