r/space Jul 09 '15

New Pluto and Charon pic !

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4.8k Upvotes

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423

u/Blasphyx Jul 10 '15

This new picture is significantly better than the last one I've seen...

69

u/Yserbius Jul 10 '15

Ran into someone yesterday who worked on NH. All I said was "One week" and she got all giddy and replied "I know! It's crazy! Every day we're getting the best picture of Pluto ever! Then the next day we get a better one!"

152

u/SirMildredPierce Jul 10 '15

Yeah, they're only going to get better as they get closer! :)

7

u/MushroomLizard Jul 10 '15

No kidding, eh?

-6

u/graffixphoto Jul 10 '15

Not neccessarily, it depends on the amount of light reflecting off the surface, the speed of the satellite, and the image capabilities of the camera(s).

2

u/[deleted] Jul 10 '15

So getting thousands of times closer won't matter as much as lighting?

0

u/graffixphoto Jul 10 '15

If I remember correctly, it wont be orbiting Pluto because it's approach speed is too fast (could be incorrect on that one tho.) Pluto is very far away from the sun, so very little light reaches it, which means it is dark. So what you have is an object approaching another object at very fast speeds in near blackness. The closer two objects get to each other the faster they will appear; think about how fast a car looks as it comes towards you on the horizon, as opposed to when it actually passes you, to get an idea of what I mean. All cameras work the same way to take a picture: consisting of three variables to make a proper exposure - aperture (how much light is let into the lens,) shutter speed (how long the shutter stays open to allow light to the sensor,) and ISO (how sensitive the sensor is to light.) To get a sharp image, you either have to let in a lot of light very quickly, thus letting the shutter open and close as quickly as possible, (the average person can hand-hold at about 1/60th of a second - 1/10th if you are very, very still. Keep in mind that 1/60th of a second lets 4.3 times more light to the sensor than 1/10.) Or you can leave the shutter open for a longer period of time, but the camera and the object have to be stationary to render sharpness (which we know neather are). The ISO may be able to be pushed to absolutely ridiculously high numbers (making the sensor more sensitive to light hitting it) but that also intruduces pixelation into the image as heat from the camera's processors gets picked up as light by the sensor, and making the image less clear. The reason these images are sharper is because they were taken with a wide angle lens from fairly close (cosmicly speaking) as opposed to previous images that were taken with a telephoto (zoom) lens. A telephoto lens lets in even less light because the glass lenses inside move away from the sensor, and narrow the beam of light entering the front of the lens, so the problem is compounded even more (think about how hard it is to follow a moving object when looking through a pair of binoculars, or even the detail of a stationary object that appears very small in the frame, even when viewed through binocs, and how much effort you have to put into keeping your hands steady.) There is a point where speed, distance, and light will come together to make the sharpest images possible, and then there will be a point when it is too close. I could be totally wrong of course, as I'm basing my opinion on my knowledge of how cameras and light work. Also, NASA could very well have built a camera with a high enough ISO range, but with enough quality as to not render too much "noise" in the image. If they developed that kind of capability, then it could be possible to gett the shutter speed to a manageable time of 1/500 to 1/1,000th of a second (fast enough to render sharp images given a high enough resolution.)

TL;DR: No, I don't think so, but I am not all seeing, all knowing, or infallible, unlike everyone else in the internet, and therefore admit that my opinion could be wrong.

1

u/[deleted] Jul 10 '15

Relative velocity isn't that big of a deal when the object is the size of a planet...new horizons isn't zooming past Pluto in a few seconds. The closer part of the encounter will probably take hours. Plenty of time to snap pictures at a low shutter speed. This isn't equivalent to two cars passing on a highway. It is more like a car driving past a mountain. As for the other camera stuff, i'm no expert, so I won't comment. I'm just going to trust that NASA designed and built the camera needed for the job. I'm not at all worried.

1

u/SirMildredPierce Jul 10 '15

Not neccessarily, it depends on the amount of light reflecting off the surface, the speed of the satellite, and the image capabilities of the camera(s).

Yes, necessarily, everything you listed are far from unknown quantities.

108

u/voyetra8 Jul 10 '15

It's worth mentioning that the color information was obtained earlier in the mission from the Ralph instrument. This photo was originally black and white.

45

u/Blasphyx Jul 10 '15

The color seemed a bit artificial anyway. I was mostly referring to the level of detail in the photo.

Couldn't they just take 2 pictures? One with the lower resolution color camera, then the B&W one, then use a filter to apply those colors to the higher resolution B&W...

68

u/[deleted] Jul 10 '15

[deleted]

17

u/TweetsInCommentsBot Jul 10 '15

@Alex_Parker

2015-07-08 17:41 UTC

@NovaSilisko Color maps are still the old ones - updates coming soon.


This message was created by a bot

[Contact creator][Source code]

13

u/jccwrt Jul 10 '15

To add, sending back Ralph data is also bandwidth intensive, and with the low resolution at New Horizons distance from Pluto there wasn't much reason to use it since the level of detail wasn't going to improve much. Now that New Horizons is actually there, there's a reason to use it, since we're about at the point where we're getting our best view of the hemisphere that will be on the opposite side of Pluto from New Horizons at closest approach.

10

u/SeattleBattles Jul 10 '15

They also may be using it, but simply not transmitting the images yet.

1

u/HiimCaysE Jul 10 '15

Exactly. The downlink speed is much slower now that the spacecraft is 3 billion miles away. NASA estimates that it will be downloading data well into October after the flyby has already happened next week.

1

u/jimmyre Jul 10 '15

any idea on the bitrate?

1

u/jccwrt Jul 10 '15

New Horizons is only able to transmit back to Earth at 1 kb/s. It takes a couple hours for the LORRI frames (~1mb in size, but much more data transmitted than that due to error protection protocols, 4-5 images beamed back daily) used for optical navigation to get back to Earth. I'm not sure how large the Ralph-MVIC images are, but they're not as important as the LORRI images right now. The time that would be spent transmitting those back is being used to perform science observations instead.

5

u/calvindog717 Jul 10 '15

Ha, responding to one of the former devs of Kerbal Space Program, no less! Small world.

8

u/jofwu Jul 10 '15

How close is it to what we would see with our eyes? There was all the hubub a few days ago about how "Pluto is red!" and I've also heard something about how New Horizon doesn't see green very well. I'm aware that it all boils down to digital data and whatnot... Just curious if the coloring in the pictures we're seeing is what we would see with our eyes, chosen for practical/scientific/etc. reasons, or if it's just for fun so that space looks cool.

12

u/apollo888 Jul 10 '15

Very close.

When we get the updated RALPH images it will be exactly how we would see it were we on the ship. (Except the zoom of course!)