Reddest object in solar system

[R36Coach]

This topic has been a debate between various sources. Some list Amalthea, others Sedna. But there seems to be no authoritative consensus on which is really the "reddest". Or is it Io?

 

[3488]

Hi there, welcome back, you disappeared after a short while last time, but you posted some great stuff.

Great question. It is not Mars, although Mars is certainly the reddest major body in the solar system aside from Io possibly. However Io is more of a yellow rather than red (see my avatar, pretty well true colour) & Mars is a deep orange - red generally.

Amalthea as you correctly say is extremely red & is a great contender. Sulphur from Io coats Amalthea & the extra redness is due to the radiation envorinment & lower temperatures. Also Amalthea's neighbours, Metis, Adrastea & Thebe should also be very red.

Sedna also appears extremely red as does the Centaur object 5145 Pholus. I really do not know for sure.

I will investigate.

Andrew Brown.

 

[MeteorWayne]

It's certainly not Io. What do you mean by "reddest"? There are many possible definitions. Within the visual bands? Including IR or microwave frequencies? Self emitters or reflectors? Are you including the CMBR, which is certainly the most red shifted?

Welcome to Space.com, where questions asked need to be specific enough to be answered

 

[3488]

Hi Wayne

I automatically assumed that R36Coach meant the reddest visually. Perhaps that's a symptom of my Autism :?: :?: :?:

I would imagine, Jupiter, Saturn & Neptune with excess intenral heat would be strong in IR, as would Venus & the day side of Mercury, perhaps hot spots on Io.

Of course the CBM, which is also in the solar system, IIRC is microwave radiation is even 'redder' than IR.

Andrew Brown.