Slashdot Mirror
NASA Unveils Historic Pictures of Pluto
An anonymous reader writes: The New Horizons team held a press briefing today and released new data and high-resolution photographs of Pluto. Alan Stern, lead researcher of New Horizons said: "We now have an isolated, small planet that's showing activity after four and a half billion years. We've settled the fact that these very small planets can be active for a long time, and I think that's going to send a lot of geophysicists back to the drawing board."
Did he just say ... "planet"?
File under 'M' for 'Manic ranting'
I TOLD you it was a planet. :)
I've fallen off your lawn, and I can't get up.
TFS contains a link to tha NASA main page, and to a finished
live stream on an unrelated media site, now without content.
Way to go!
NASA press release, with picture.
The detailed image showing Pluto's mountains is, according to one of the NASA scientists, one the youngest looking bodies in the solar system. The surface features appear to be less than 100 million years old. Very strange. Are there even any viable theories on what is providing the energy to resurface such an old, far-out, isolated body? A major impact of some kind is the only thing I can think of. Pluto is too small for the heat to be internally generated, and there is no massive nearby body to cause tidal forces and the like.
Better known as 318230.
There's a photo on xkcd.
Get free satoshi (Bitcoin) and Dogecoins
In the feed NASA stated they both locked up early on and ruled out tidal forces as being a factor.
PS: I don't reply to ACs.
take me to a guardian article instead of NASA's image gallery? Oh that's right, the editors are here to collect a paycheck and maintain their morbid obesity by doing as little as possible.
watch the feed. What they've discovered so far has already challenged and thrown out many hypotheses about planet formation/evolution. It may look like a rock to the untrained eye - but what humanity knows about planetary physics has already changed because of this probe. It's impossible to know where and how this will change our theories and even technology down the road.
PS: I don't reply to ACs.
People keep referring to a heart shaped image on the surface of Pluto but is looks like a dogs head, snout to the right and ear on the left. Very similar to this image.
The character
http://www.cliparthut.com/clip-arts/451/pluto-disney-451536.gif
The celestial body
http://graphics8.nytimes.com/newsgraphics/2015/07/15/pluto-flyby-images/assets/150713-pluto-before-flyby.jpg
Comment removed based on user account deletion
Well, Hydra could certainly use a little more jpeg.
In the feed NASA stated they both locked up early on and ruled out tidal forces as being a factor.
One of the panel-members said tidal heating was no longer a factor.
Perhaps you and the GP are both right?
If it weren't for deadlines, nothing would be late.
I was surprised at how low resolution the picture of Hydra was - like 10px by 5px. :-) Didn't they take any higher-res shots of it than that? You'd think they'd pick one of the higher res ones to send first if so.
== Jez ==
Do you miss Firefox? Try Pale Moon.
Do realize that LORRI isn't just a camera, it's actually more of a telescope. And they can expose the images as long as they want, and even stack them if they want.
If you think it's hard to get pictures on the sunlit side, that's nothing - they actually plan to try to get pictures on the side *not* lit by the sun, just by the pathetically weak light reflected by Charon. Getting images on the lit side is easy, but the dark side is going to be very difficult, involving lots of stacking.
"You see, Government is a system that is based on weapons." -- Timster
Since the amount of light that is cast on an object is exponential with regard to distance
You mean inverse-square with respect to distance. The inverse-square law applies when the source is a point (or uniformly-luminous sphere that is far enough away.)
Pluto is about 40 AU away from the Sun, whereas the Earth is 1 AU away. That means sunlight on Pluto's surface is about 1/40^2 = 1/1600 as bright as on the Earth's surface. That's dim, but not hard to record with good optics, a sensitive detector, and enough exposure time.
If it weren't for deadlines, nothing would be late.
The best part: With xkcd's audience, there's a good chance those names will become official.
Last post!
It's still really bright at Pluto. Sunny area would be around 60 lux, which is about 9 EV in photography exposure (ISO100 EV scale).
Think office interiors, art gallery, stage show, indoor sports, etc.
Not very dim at all.
The main imager (LORRI) is a 208mm diameter telescope with a 2630mm focal length, or f/12.6. The spider and secondary obscure 11% of the area, so that's equivalent to f/13.4 in terms of light gathering for photographic purposes. Exposure times are 50-200 ms, or 1/20 to 1/5 sec.
On Earth, the sunny 16 rule says on a sunny day the proper exposure at f/16 is when your shutter speed is 1/ISO. So f/16, 100 ISO, 1/100 sec. The atmosphere absorbs roughly half the sunlight, so in earth orbit that would become f/16, 100 ISO, and 1/200 sec.
Pluto is about 32.6 AU from from the sun right now, so the sun's brightness there is 1/32.6^2 = 1/1063 what it is at Earth.
Going from f/16 to f/13.4 gets you about 1.43x more light.
Increasing exposure time from 1/200 sec to 1/10 sec gets you 20x more light.
That leaves a deficit of 37.2x, which you can get by increasing CCD sensitivity to ISO to 3,720.
ISO 3200 was easily attainable by high-end consumer digital camera sensors 10 years ago, much less a commercial one specially designed for scientific purposes.
In terms of brightness these pictures of pluto are about as bright as some backyard telescope achievements. That's how we found it to begin with. When you have a camera you have the ability to control exposure duration, then it just becomes a waiting game while your sensor is counting photons. The longer you count photons for the brighter the image providing the noise level isn't creeping up.
It's very similar to the way people do 30+ hour photos of nebula and the like, it's able to resolve light that simply too faint for the naked eye.
I was talking to my son about the New Horizons mission today and explained to him that scientists LOVE it when they look at something and think "I have no clue why this is the way it is." That's one of the best moments in science. That means you have a mystery to solve. The worst thing any scientist can think is "We know everything there is to know about this thing." Science thrives on unraveling the unknown. The day when we know everything there is to know about everything is the day science dies. (Granted, I doubt that day would ever come as there's always more to learn.)
My sci-fi novel, Ghost Thief, is now available from Amazon.com.