Questions about GOES Magnetometer?

[oemSpace]

 

The GOES Hp plot contains the 1-minute averaged parallel component of the magnetic field in nanoTeslas (nT), as measured at GOES-13 (W75) and GOES-15 (W89). The Hp component is perpendicular to the satellite orbit plane and Hp is essentially parallel to Earth's rotation axis. If these data drop to near zero, or less, when the satellite is on the dayside it may be due to a compression of Earth's magnetopause to within geosynchronous orbit, exposing satellites to negative and/or highly variable magnetic fields. On the nightside, a near zero, or less, value of the field indicates strong currents that are often associated with substorms and an intensification of currents in the Earth's geomagnetic tail.

Noon and midnight local time at the satellite are plotted as N and M. Default scaling is 0 to 200 nanoTesla. Non-default scaling to include infrequent extreme values is lableled in red to emphasize the change in scale.

Source : http://www.swpc.noaa.gov/rt_plots/mag_3d.html

 

When both data go from 110 (on 3 Sep at noon) to 70 (on 4 Sep at midnight), it seems that the magnetic field (MF) at noon is always higher than MF at midnight.  I don't understand what cause the difference in MF in different periods, and would like to know more about this natural behavior.

 

Does anyone have any suggestions?

 

Thanks in advance for any suggestions :>

[Vancanneyt Sander]

If you've read the description of the GOES Hp, the awsner is in the description of that.. so read it again and particulary the parts of where the satellite is at the day or nightside which are also different in readings.

It's normal that the readings are different, on the nightside the satellite is in the magnetotail and gets more influenced by the substorms that form there; on the dayside it's a different story.

[oemSpace]

 

 

If these data drop to near zero, or less, when the satellite is on the dayside it may be due to a compression of Earth's magnetopause to within geosynchronous orbit, exposing satellites to negative and/or highly variable magnetic fields.

 

On the nightside, a near zero, or less, value of the field indicates strong currents that are often associated with substorms and an intensification of currents in the Earth's geomagnetic tail.

 

SInce the orbit of GOES satellites is around the Earth, should we compare the strength of magnetic field using M to M and N to N rather than M to N?  If this is the case, at this current moment, strength of MF at midnight between 3 & 4 Sep seems keeping on the same levels and slightly rising, and strength of MF at Noon between 2 & 3 Sep seems rising.  So can I conclude following statement:

 

• On the dayside, the Earth's magnetopause seems expanding within geosynchronous oribit
• On the nightside, the magnetic field indicates weaker currents in the Earth's geomagnetic tail.

Will it be corrected statement?

 

Do you have any suggestions?

 

Thanks you very much for any suggestions :>

 

 

[Vancanneyt Sander]

Depending on the solar wind on the dayside, the magnetosphere bubble is bigger or bit less bigger. It Always is under influence of the solar wind as it id blowing on it. On the nightside there is no wind but due to the solarwind we get the magnetotail and so the sattellite is less influenced, unless magnetic substorms occur.

[oemSpace]

I would like to know how you use and interpret this charts.

 

Do you have any different interpretation from mine?   

 

Thanks you very much for any suggestions :>

[Vancanneyt Sander]

We don't do interpretations, our explanations are facts ;-) no suggestions. I follow solar activity for more than 10 years so then you'll know what it's al about and how it works.

For us, the GOES Hp graph is not very important, it's more used by satellite operators because they need that info to make sure their satellites are in a safe environment. So unless you're in the satellite business, you don't realy need this graph.

[Marcel de Bont]

I would like to know how you use and interpret this charts.

 

Do you have any different interpretation from mine?   

 

Thanks you very much for any suggestions :>

It's all on the website you quoted, everything you need to know. If the line is going up and down in a very regular motion then geomagnetic conditions are quiet. This is completely normal as the satellite moves from the dayside to the nightside and back again. If the line goes significantly down then it can indicate storming. It is however better to use ground based magnetometers, preferably close to your location. As Sander mentioned, the GOES Hp graph is more for satellite operators.

[oemSpace]

It's all on the website you quoted, everything you need to know. If the line is going up and down in a very regular motion then geomagnetic conditions are quiet. This is completely normal as the satellite moves from the dayside to the nightside and back again. If the line goes significantly down then it can indicate storming. It is however better to use ground based magnetometers, preferably close to your location. As Sander mentioned, the GOES Hp graph is more for satellite operators.

 

Thanks everyone very much for suggestions :>