Could New Horizons look back just after leaving Pluto?

Status
Not open for further replies.
W

willpittenger

Guest
I think it would be a good idea if New Horizons looked back at the Sun after leaving Pluto. That would help people realize just how tiny the sun is. If it can also create a image like the last image from Voyager (the entire inner solar system in one mosaic), that might be good too. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>
 
V

vogon13

Guest
I would prefer the camera not be burned out until after the 2 KBO encounters . . . .<br /><br /><img src="/images/icons/frown.gif" /><br /><br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>
 
V

vogon13

Guest
Why take a chance <i>before</i> the KBO flybys?<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>
 
C

comga

Guest
The Sun would not damage either the LORRI or Ralph instruments. That is why the protective doors are open. At Pluto, the solar flux is 1/1000 of what it is near the Earth, 1.4 Watts per square meter. I think that's 6 milliwatts into Ralph and 42 milliwatts into LORRI, IIRC.<br /><br />Alice plans to look back at the Sun, but through a solar occultation portm not its main aperture. This will be done to characterize the atmosphere on Pluto as the spacecraft enters and leaves Pluto's shadow.<br /><br />It is not clear whether a useful image could be obtained. And images, especially telephoto images with high sensitivity, would only show what the image processing is made to bring out. There is no absolute sense of scale or brightness. It would just be a small disk. One could say it was anything, a planet, a moon, the Sun, a planetary nebula. Even stretching the dynamic range, the rest of the image would be black.
 
3

3488

Guest
Yes, it would it possible, but lets wait until after any other KBO encounters after Pluto.<br /><br />From Pluto the Sun is still about 1,600 times brighter than the full moon. One would have to go out to a massive 640 AU for the sun to appear the same brightness as the full moon.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
C

CalliArcale

Guest
I hope they do make a second solar system portrait once the primary mission is over. It'll have little scientific value, but the one by Voyager still brings tears to my eyes. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>
 
3

3488

Guest
I would not be surprised if that will be tried. I do agree, the Voyager 1 solar system portrait IMO is still one of the greatest space images ever. Shows how small the Earth is!!<br /><br />Another thing could be to try & observe Eris from afar to get light curves, spectra, etc from different phase angles, as New Horzizons will do with Pluto after the upcoming Jupiter encounter.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
M

MeteorWayne

Guest
I suppose that would depend on where Eris will be in 2016 when NH passes Pluto.<br />That sound like an interesting project to research, and since I'm feeling better, I might justvtry it. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
3

3488

Guest
Hi MeteorWayne,<br /><br />Great to hear from you again my freind & good to hear that you are feeling better!!<br /><br />I will look on Celestia tonight & will check how far & position of Eris as seen from Pluto in 2016. <br /><br />Pluto & Eris AFAIK are closer to each other now than when New Horizons made the initial Pluto observation with the LORRI camera last year (from the Sun & Earth Pluto in Serpens Cauda, Eris in Cetus). <br /><br />In 2016, they should be slightly closer to each other yet, as Pluto is orbiting the Sun slightly faster than Eris. I think that the light curve & spectra readings might work.<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>
 
M

mithridates

Guest
That's an interesting number. Is there anything else that can be compared to? 1600 times brighter than the full moon is hard to imagine. The brightness of the sun on a heavily overcast day? I can't imagine exactly what the sun would look like from there.<br />That reminds me of the page on Alpha Centauri on Wikipedia - last year or the year before I requested that someone write a description of what the sky would look like from a planet in around the same position as the Earth around each of the stars and the detailed description of how the two suns would look in the sky was extremely interesting. Very Tatoiine-ish. <div class="Discussion_UserSignature"> <p>----- </p><p>http://mithridates.blogspot.com</p> </div>
 
M

mrmorris

Guest
<font color="yellow">"That's an interesting number. Is there anything else that can be compared to? 1600 times brighter than the full moon is hard to imagine. "</font><br /><br />OK -- Google to the rescue again. I located the following from a NASA educational site and pasted the Pluto-relevant bits below:<br /><br /><br /><br /><i>"It has been thought by many people even perhaps a few astronomers that from Pluto, the Sun would seem no brighter than does Venus from our skies. If we use as the distance from the Sun to Pluto a value of 3.5 billion miles and apply the inverse square law, we can estimate how much light actually strikes the surface of little Pluto and its puny satellite, Charon. Think of the inverse square law this way; if an object, such as the Sun, were to somehow suddenly move twice as far away as it is now, it would appear four times dimmer. Conversely, if it were to move twice as close as it is now, or about 47 million miles away, it would be four times brighter. Since Europa is 5 times more distant from the Sun than are we, an astronaut on its surface would see a Sun that is only 1/25 as bright - no wonder Europa is cloaked in ice. For someone on Titan, the Sun would appear only about 1/100 as bright as it does from Earth, and for someone on Pluto, the Sun would only be about 1/1400 as bright as the Sun when viewed from Earth. It would seem that an astronaut would need a good pair of binoculars just to see old Sol.<br /><br />But even something 1/1400 as bright as the Sun is still pretty darn bright. Celestial objects are assigned apparent magnitudes that give us a relative sense of their brightness. The more negative the number, the brighter the object. An object with a magnitude of -1 is 2 1/2 times as bright as an object with a magnitude of -2, and about 6.25 times brighter than a object that has a magnitude of -3. A magnitude difference of 15 amounts to</i>
 
Status
Not open for further replies.

Latest posts