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Hayabusa 2 rovers send new images from Ryugu surface

bbc.co.uk

11–20 of 60 posts

Re: Hayabusa 2 rovers send new images from Ryugu surface

#11
post #2

Just came back from Europe. Everyone knows about this and all media reported on it. Surprisingly so little is said in American media. Its not new that Americans do not like other nations succeed in space! If these were US-based rovers, each network will give it 10 minutes cover. Same sad story about Chinese Moon landing. Most American friends laughed at me when I told them China landed rover on moon. Some even questi…

It's even worse in music, movies, and sports.

Re: Hayabusa 2 rovers send new images from Ryugu surface

#12

I love that they opted for color cameras. Not much color to be seen, but the flares, together with the motion blur (while falling and hopping!) make the pictures look really dynamic. :)

Wonder if it's because they were planning on taking pictures while hopping? The usual one-picture-per-color-filter method that they usually use on space probes probably wouldn't work well while in relatively fast motion.

Re: Hayabusa 2 rovers send new images from Ryugu surface

#13

The pictures are thrilling! The rock looks stratified - which might imply they were created under gravity? Or is it just the camera angle...

Less gravity, more radiation/light. There is lots of water/ice involved, and the rock varies in distance from the sun. So the layered effect is probably the result of different temperatures at various depths, and the resulting sublimation (or not) of water ice. Imho it is akin to the layered effect in soil during a hard frost.

Re: Hayabusa 2 rovers send new images from Ryugu surface

#15
post #9
post #2

Just came back from Europe. Everyone knows about this and all media reported on it. Surprisingly so little is said in American media. Its not new that Americans do not like other nations succeed in space! If these were US-based rovers, each network will give it 10 minutes cover. Same sad story about Chinese Moon landing. Most American friends laughed at me when I told them China landed rover on moon. Some even questi…

Consider literal competitions--it was similarly appalling to watch recent Olympics in the US. 95% or more of the coverage was of Americans winning. If a particular day had fewer wins, they would replay earlier footage rather than dare show any other country succeeding at non-American dominant areas. One saving grace is that the NBC app had all the footage they didn't deem worthy of broadcasting.

I can't watch the Olympics on US TV. Hours of stories about the upbringing of the US athletes interviewing moms and grandparents. Then a little actual sport if you are lucky. And certainly nothing where there isn't a US athlete/team at the front. It's unbearable.

Re: Hayabusa 2 rovers send new images from Ryugu surface

#17
post #2

Just came back from Europe. Everyone knows about this and all media reported on it. Surprisingly so little is said in American media. Its not new that Americans do not like other nations succeed in space! If these were US-based rovers, each network will give it 10 minutes cover. Same sad story about Chinese Moon landing. Most American friends laughed at me when I told them China landed rover on moon. Some even questi…

>> Some even question Wiki article as conspiracy theory.

Is there a Wikipedia page that "some" Americans don't think is a conspiracy? Conspiracies used to be about aliens and secret research programs in bunkers. Now they are about pizza restaurants. I gave a presentation at an Airforce base where a flat-earther accused me of participating in the conspiracy. I wanted to throw him out as a dangerous or unstable person, or strap him to the underside of a plane and show him the curve in person. These days, every article, every statement, has to address the 5-10% of people who just don't believe anything anyone tells them.

I am waiting for one of the "airplanes run on compress air" conspiracy people. (It's the latest version of chemtrails.) We'll have them fill a few aircraft by hand... with buckets.

Re: Hayabusa 2 rovers send new images from Ryugu surface

#19
"Gravity on the surface of Ryugu is very weak, so a rover propelled by normal wheels or crawlers would float upwards as soon as it started to move," officials with the Japan Aerospace Exploration Agency (JAXA) wrote in a description of MINERVA-II1A and MINERVA-II1B.

So, the robots — each of which measures 7 inches wide by 2.8 inches tall (18 by 7 centimeters) and weighs 2.4 lbs. (1.1 kilograms) — hop instead. They do this by moving a "torquer" in their interior, which rests atop a disk-shaped turntable.

By rotating the torquer, a reaction force against the asteroid surface makes the rover hop with a significant horizontal velocity," a team of researchers led by JAXA's Tetsuo Yoshimitsu wrote in a 2012 study outlining the concept. "After hopp[ing] into the free space, it moves ballistically. With this mechanism, by changing the magnitude of torque, the hopping speed can be altered, so as not to exceed … the escape velocity from the asteroid surface.

Src: https://www.space.com/41941-hayabusa2-asteroid-rovers-hoppin...

Re: Hayabusa 2 rovers send new images from Ryugu surface

#20
post #18

I'm sure it's a very complicated problem, but I would have expected a 5 year old rover to have a better camera. I am a bit shocked at the potatoness of it.

I'm pretty sure it's not a poor camera because they couldn't afford it. It'll be because of weight considerations. If you have a higher resolution camera, everything has to be bigger and heavier - larger camera, more local storage, more processing power, bigger antenna (these have to be sent using lossless compression for science), etc. Each robot has a mass of 1.1 kg, lighter than my laptop - and it has to do other science and return a sample to earth!
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