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Radar reveals two moons orbiting asteroid Florence

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Re: Radar reveals two moons orbiting asteroid Florence

#2
Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here.

I suppose terrestrial radar looks at much smaller objects and what it sees is emitted from the tower and bounced back in a straight line so that sort of makes sense.

More info on the observatory: https://en.wikipedia.org/wiki/Goldstone_Solar_System_Radar

Re: Radar reveals two moons orbiting asteroid Florence

#3
post #2

Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here. I suppose terrestrial radar looks at much smaller objects and what it sees is emitted from the tower and bounced back in a straight line so that sort of makes sense. More info on the observatory: https://en.wikipedia.org/wiki/Goldstone_Solar_System_Radar

> Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here.

Yes it's emitted from the sun, it's clear given that the time-lapse shows "Inner moon eclipsed" when passing behind the site of the asteroid that is not lit.

Re: Radar reveals two moons orbiting asteroid Florence

#4
post #3
post #2

Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here. I suppose terrestrial radar looks at much smaller objects and what it sees is emitted from the tower and bounced back in a straight line so that sort of makes sense. More info on the observatory: https://en.wikipedia.org/wiki/Goldstone_Solar_System_Radar

> Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here. Yes it's emitted from the sun, it's clear given that the time-lapse shows "Inner moon eclipsed" when passing behind the site of the asteroid that is not lit.

I don't understand how the phrase 'inner moon eclipsed' tells the reader that the source of radiation for this radar measurement is the sun.

Re: Radar reveals two moons orbiting asteroid Florence

#6
post #4
post #3

Earlier quoted context omitted.

> Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here. Yes it's emitted from the sun, it's clear given that the time-lapse shows "Inner moon eclipsed" when passing behind the site of the asteroid that is not lit.

I don't understand how the phrase 'inner moon eclipsed' tells the reader that the source of radiation for this radar measurement is the sun.

I don't either :) but sort of a silly question I guess. I presumed it was the sun due to the angle of illumination as well as common sense that the sun is probably the brightest object in the solar system along multiple bands of light; I was really just amazed at the relatively large amount of detail in the image.

Re: Radar reveals two moons orbiting asteroid Florence

#7
post #3
post #2

Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here. I suppose terrestrial radar looks at much smaller objects and what it sees is emitted from the tower and bounced back in a straight line so that sort of makes sense. More info on the observatory: https://en.wikipedia.org/wiki/Goldstone_Solar_System_Radar

> Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here. Yes it's emitted from the sun, it's clear given that the time-lapse shows "Inner moon eclipsed" when passing behind the site of the asteroid that is not lit.

I was always under the assumption that with Radar images that it didn't rely on a light source as technically the radar is the source. So that the impression that there is a light an dark side was based purely on the motion towards and away from the receiver.

But, you have pointed out something interesting and that would appear to indicate other wise. The clear rotation independent of source already shows that I am wrong on that.

Apparently I don't understand this very well.

Re: Radar reveals two moons orbiting asteroid Florence

#8
post #5

Imagine hijacking a 100-meter moon made of rare earth metals like gold, platinum, rhodium, ruthenium, iridium, etc. etc. More than enough to under write the mission and pay for a moon base.

Unless you did it very secretly and slowly you'd might crash the market though.

Re: Radar reveals two moons orbiting asteroid Florence

#9
post #5

Imagine hijacking a 100-meter moon made of rare earth metals like gold, platinum, rhodium, ruthenium, iridium, etc. etc. More than enough to under write the mission and pay for a moon base.

Imagine heating and spinning it into a thin foil disk, and then curving it into a slight parabola by gently accelerating the center point away from the sun. Solar-cooker death-ray for anyone who disputes your claim!

Re: Radar reveals two moons orbiting asteroid Florence

#10
post #4
post #3

Earlier quoted context omitted.

> Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here. Yes it's emitted from the sun, it's clear given that the time-lapse shows "Inner moon eclipsed" when passing behind the site of the asteroid that is not lit.

I don't understand how the phrase 'inner moon eclipsed' tells the reader that the source of radiation for this radar measurement is the sun.

Well, if the illumination was from the radio telescope, then the moon would be hidden behind the parent asteroid when it is eclipsed. We would not see it go dark, it would just be obscured.
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