How they detect and plot the magnetic field of other planets and our moon??

Question

How do the scientists do it. How do they know the magnetic poles of other planets, and how do they make maps of it. On earth it is simple for us.

Answer 1

A magnetometer is a scientific instrument used to measure the strength and/or direction of the magnetic field in the vicinity of the instrument. The spacecraft that have been sent to the other planets (and all 7 other planets plus several satellites have had probes sent to them or past them) have many different instruments on board - a magnetometer is one such instrument.

The magnetic field of a star can be measured by the Zeeman effect. Normally the atoms in a star's atmosphere will absorb certain frequencies of energy in the EM spectrum, producing characteristic dark absorption lines in the spectrum. When the atoms are within a magnetic field, however, these lines become split into multiple, closely-space lines. The energy also becomes polarized with an orientation that depends on orientation of the magnetic field. Thus the strength and direction of the star's magnetic field can be determined by examination of the Zeeman effect lines.
A stellar spectropolarimeter is used to measure the magnetic field of a star. This instrument consists of a spectrograph combined with a polarimeter.

Answer 2

At this time, most data that we have gotten regarding other planet's magnetic fields have been from probes that we have sent to the subject body. There may be some ways to detect from here, but the best way is to send something there.

That being said, we know enough about how magnetic fields are produced to predict the strength of other planet's fields (if they have one)

Answer 3

all of them do, yet at various stages. it rather is how they could slingshot sattelites to the place they prefer them. If different planets and moons had no magnetic field, sattelites could run previous without trajectory exchange. Even the solar has magnetic fields, which in case you watch movies of, rather pull the image voltaic flares back to the outdoors most of the time.