Starship Asterisk*

Chris Peterson wrote:

geckzilla wrote:

Chris Peterson wrote:Try rendering with different viewing distances, and note the point where you can no longer tell that the planets are oblate.

I dunno, when viewed face on, it has to go pretty far. Down until the difference is less than a pixel and even then you could tell if you zoomed in close enough and added up the brightness of each pixel. I guess the higher (or lower) the inclination it's being viewed from, the less obvious it would be.

Wrong direction. How close do you need to get before you can't detect the oblateness? A lot of the NASA renderings are views from orbit, where you see much less than a hemisphere, and that will result in a circular projection.

geckzilla wrote:

Chris Peterson wrote:Try rendering with different viewing distances, and note the point where you can no longer tell that the planets are oblate.

I dunno, when viewed face on, it has to go pretty far. Down until the difference is less than a pixel and even then you could tell if you zoomed in close enough and added up the brightness of each pixel. I guess the higher (or lower) the inclination it's being viewed from, the less obvious it would be.

Chris Peterson wrote:

geckzilla wrote:

skyhound wrote:Am I the only one who looks at renderings of Jupiter like this and thinks, "Wrong, wrong, wrong?" (measures Jupiter on screen both ways) Jupiter is not a sphere. It is flattened at the poles to a numerically small, but distinguishable degree. When you consider the calculations that go into making an animation like this to appear accurate accurate, I'll never understand why so few take the time to get the oblateness right. It does make it easy to discern a simulation from the real thing though, at least for me.

You are not alone. This pet peeve doesn't pertain to this APOD at all, but yeah. I think to myself, come on, how hard is it to add a little flattening to that sphere you just created? Not hard at all. Here you go, have some planets I rendered a while back.

Try rendering with different viewing distances, and note the point where you can no longer tell that the planets are oblate.

geckzilla wrote:

skyhound wrote:Am I the only one who looks at renderings of Jupiter like this and thinks, "Wrong, wrong, wrong?" (measures Jupiter on screen both ways) Jupiter is not a sphere. It is flattened at the poles to a numerically small, but distinguishable degree. When you consider the calculations that go into making an animation like this to appear accurate accurate, I'll never understand why so few take the time to get the oblateness right. It does make it easy to discern a simulation from the real thing though, at least for me.

You are not alone. This pet peeve doesn't pertain to this APOD at all, but yeah. I think to myself, come on, how hard is it to add a little flattening to that sphere you just created? Not hard at all. Here you go, have some planets I rendered a while back.

skyhound wrote:Am I the only one who looks at renderings of Jupiter like this and thinks, "Wrong, wrong, wrong?" (measures Jupiter on screen both ways) Jupiter is not a sphere. It is flattened at the poles to a numerically small, but distinguishable degree. When you consider the calculations that go into making an animation like this to appear accurate accurate, I'll never understand why so few take the time to get the oblateness right. It does make it easy to discern a simulation from the real thing though, at least for me.

chuckster wrote:

BillT wrote:
On Pluto the Sun is between 150 and 450 times as bright as the full Moon as seen from Earth. The range of brightness relates to Pluto's elliptical orbit. Even when Pluto is at aphelion, you would have no trouble seeing stuff on Pluto's day side.

I never would've believed the inverse square law left nearly that much sunlight on a planet surface that's 15 light hours distant.

BillT wrote:On Pluto the Sun is between 150 and 450 times as bright as the full Moon as seen from Earth. The range of brightness relates to Pluto's elliptical orbit. Even when Pluto is at aphelion, you would have no trouble seeing stuff on Pluto's day side.

• since we last sent a spacecraft to Jupiter.

chuckster wrote:
How can Juno survive, at Jupiter, on solar panels?
I always thought the outer solar system demanded RTG's ?

• since we last sent a spacecraft to Jupiter.

https://en.wikipedia.org/wiki/Solar_cell_efficiency wrote:

[b][color=#0000FF]Reported timeline of solar cell energy conversion efficiencies since 1976 (National Renewable Energy Laboratory) [/color][/b]

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https://en.wikipedia.org/wiki/Juno_(spacecraft)#Solar_panels wrote:
<<The Juno spacecraft uses three solar panels with a total area of 60 m² the biggest on any deep-space probe except for Rosetta's 64 m². The combined mass of the three panels is nearly 340 kg. If the panels were optimized to operate at Earth, they would produce 12 to 14 kilowatts of power. Only about 486 W will be generated when Juno arrives at Jupiter, declining to near 420 W as radiation degrades the cells. The solar panels will remain in sunlight continuously from launch through to the end of the mission, except for short periods during the operation of the main engine. A central power distribution and drive unit monitors the power that is generated by the solar panels, distributes it to instruments, heaters and experiment sensors as well as batteries that are charged when excess power is available. Two 55-amp-hour lithium-ion batteries that are able to withstand the radiation environment of Jupiter will provide power when Juno passes through eclipse.>>

chuckster wrote:Dumb question : How can Juno survive, at Jupiter, on solar panels ? I always thought the outer solar system demanded RTG's ?

MarkBour wrote:I hope Juno returns great analytical data on the cloud composition and can do it with high resolution. For instance, I'd like to know if we can find out whether the great red spot or any other cloud band has differing composition than other bands, zones, or belts. I think we will find many surprising discoveries from such an investigation.

Wadsworth wrote:Does anyone else naturally see this picture to be on its side? My mind wants to rotate it 90 degrees.

Boomer12k wrote:

Mactavish wrote:
My door doesn’t seem to be a jar. What kind of jar do you have? None of my doors have a lid. I can see through all of my jars. Besides, what good is a door if you can see through it?

A door you can see through, you know who is there, but you are safer... and a screen door you can see through but the bugs stay out... plenty purpose for doors you can see through...*

neufer wrote:

Chris Peterson wrote:
somehow I worked out the correct interpretation without even giving it conscious thought!

Yes...but that was entirely irrelephant to what I was talking about.

Mactavish wrote:

Tszabeau wrote:

r.webber@zen.co.uk wrote:So Jupiter is on its way to Pluto. Dreadful grammar error!

Your door is a jar.

My door doesn’t seem to be a jar. What kind of jar do you have? None of my doors have a lid. I can see through all of my jars. Besides, what good is a door if you can see through it?