Japan's Hayabusa2 Spacecraft Reaches 'Spinning-Top' Space Rock Ryugu (space.com)

Zorro shares a report from Space.com: The Japanese spacecraft Hayabusa2 has successfully rendezvoused with Ryugu, beginning an 18-month stay at the diamond-shaped asteroid. Launched by the Japan Aerospace Exploration Agency, JAXA, in 2014, the probe will poke, prod and even impact the asteroid, deploying a small lander and three rovers. It will then blast an artificial crater to analyze material below the asteroid's surface. After that, the probe will head back to Earth, arriving near the end of 2020 with samples in tow.

Hayabusa2 automatically fired its thrusters this morning (June 27) at 9:35 a.m. local Japanese time (8:45 p.m. on June 26 EDT, or 1245 GMT), bringing the probe within a constant 12 miles (20 kilometers) of the asteroid, according to a statement from JAXA. The Hayabusa2 team will have to select the best place for the probe's lander and rovers based on the space rock's spinning-top-like shape and its rotation; the 3,000-foot-wide (900 meters) asteroid rotates perpendicular to its orbit, completing a full rotation every 7.5 hours.

Comments

A few relevant comments

[hcs_$reboot]

A few years ago, a Japanese probe missed Venus, an however easier target, so there is some progress that's been made. Then, landing on the space rock is a hard objective, as for instance the ESA's Philae lander failed to complete the mission. Good luck with that - that'd be great if it succeeds and brings back some samples to Earth.

Re:A few relevant comments

[JaredOfEuropa]

Speaking of the Philae mission, I hope the Japanese have the dress code for their mission sorted out. Wouldn’t want a repeat of that failure.

Re:A few relevant comments

[Anonymous Coward]

Relevant how, exactly?

Yes, space exploration is hard. A few years ago we even managed to kill the whole crew of a shuttle mission. And few years before that we killed the whole crew of another shuttle mission.

Nobody has a perfect record.

Re:A few relevant comments

[Joce640k]

A few years ago, a Japanese probe missed Venus, an however easier target...

What about the Mars orbiter that mixed up metric/imperial and thrust itself into the planet instead of going around it? How amateur was that?

(and what sort of country still uses imperial units in the 21st century?)

Re:A few relevant comments

[hcs_$reboot]

(and what sort of country still uses imperial units in the 21st century?)

Hint: a country more and more secluded, thanks to harsh immigration measures, tougher tariffs and more arrogant behavior.

Re:A few relevant comments

[Applehu Akbar]

I, on the other hand, am hoping that all of the Hayabusa researchers wear that same Hawaiian shirt at the press conference. Japan does science, and it doesn't give a fsck what SJWs think about a subject they know nothing about.

Re:A few relevant comments

[Applehu Akbar]

What about the Mars orbiter that mixed up metric/imperial and thrust itself into the planet instead of going around it? How amateur was that?

What people don't realize about that particular fusterclck is that it was not caused by someone making a gross error in converting between units. But because science operates in SI while the military contractors who built the probe work in Imperial, months of high-precision conversions back and forth between systems, in software, caused an accumulation of tiny roundoff errors to add up to aerobraking into the wrong part of the Martian atmosphere and loss of the craft.

Re:A few relevant comments

[Type44Q]

...and what sort of country still uses imperial units in the 21st century?

That would be the only country to possess resusable rockets in the 21st Century.

What were you saying? ;)

Re:A few relevant comments

[drinkypoo]

What people don't realize about that particular fusterclck is that it was not caused by someone making a gross error in converting between units. But because science operates in SI while the military contractors who built the probe work in Imperial,

The gross error was in converting between units at all. The original question was valid. What kind of monkeys use anything but metric for working on spacecraft?

Re:A few relevant comments

[Solandri]

What about the Mars orbiter that mixed up metric/imperial and thrust itself into the planet instead of going around it? How amateur was that?

Mars Climate Orbiter was not lost because of a metric/imperical mix-up as the press likes to portray it. It was lost because one lazy person didn't write down the units on a printout of numbers, and another lazy person just assumed what the units were supposed to be instead of picking up the phone and verifying. MCO would've been lost all the same if the numbers had been printed in kilonewtons and the person keying in the numbers assumed they were newtons. No Imperial units necessary. The first thing they drilled into our heads in my undergrad engineering school was that a number without a unit was meaningless (except as a ratio), and to treat it as NaN rather than assume the units.

Roughly half the missions to Mars fail, and NASA has had the highest success rate of any space agency. The overall success rate at Venus is higher, but mostly because only the Soviets tried to land on it. Everything else has been orbiters or flybys. However, contrary to GP's claim, Venus is a harder target than this asteroid. Because of the sun's gravity well, the least-energy Hohmann transfer orbit from Earth to Venus ends up taking about 6 months. This results in a relatively large delta-V between the spacecraft and target, which needs to be precisely canceled out when the spacecraft reaches Venus in order for it to enter planetary orbit (the same operation which doomed MCO). The asteroid Hyabusa2 is encountering is a near-earth asteroid, meaning its orbital velocity around the sun is not that different from Earth's. So the spacecraft could take a more leisurely trip there (roughly 3.5 years), requiring substantially less delta-V to slow down and match the asteroid's orbit.

Re:A few relevant comments

[Gavagai80]

If you watch any SpaceX webcast, they give the speed and altitude in kilometers per second / kilometers only. Never seen them even make casual reference to an imperial unit.

Re:A few relevant comments

[drinkypoo]

Whoa, that racist comment just came out of nowhere! Why'd you have to bring race into it?

Only you brought race into it.

Re:A few relevant comments

[Agripa]

(and what sort of country still uses imperial units in the 21st century?)

One whose citizens no longer count on their fingers.

days ago

[AndyKron]

Better late then never I suppose. I've already seen this, posted it on Facebook and forgot about it days ago

Re:days ago

[hcs_$reboot]

They just wanted to be sure!

SpaceX

[110010001000]

Too bad they didn't go with SpaceX for the launch. They would have saved a few bucks. Plus they would have been able to reuse the rocket and it could have been used in the fleet launch to Mars.

Don't underestimate the difficulty of this.

[Anonymous Coward]

Landing on something that small, in the middle of nowhere, is quite an amazing feat. Because it is so hard to miss, in terms of velocities. Bringing *back* material is just damn amazing.
Yes, those mars landers had great landing procedures. But this here is far more fascinating and alien to me.

Re:Don't underestimate the difficulty of this.

[vtcodger]

It's not that hard to hit. But you don't want to hit it. What looks to be hard is keeping your lander and rovers "landed" on a small rock with virtually no gravity and still having them do anything useful.

Returning a sample probably isn't so hard, but how does one extract a sample without having the sample and sampling device drift off in opposite directions?

Re:sigh .. how about solving some real problems

[RandomFactor]

While not uncommon, It's not the hypocrisy of those who hold those views that is the problem.

Saying we need to achieve some sort of perfect paradise on Earth before we can spend resources on anything else that advances human knowledge is simply saying we can never again advance human knowledge.

What kind of world does that logically lead to?

Asteroid samples. Mmm...

[Type44Q]

...with samples in tow

I wonder how long it'll be before sushi dusted with powdered asteroid becomes popular in Japan.

Space survival

[spinitch]

B4 we destroy each other , space offers a chance to extend survival of advanced intelligence. Space exploration also pushes Science application and understanding which might help improve life for many vs another soft drink or sitcom. Yet Japan will expend an inordinate amount of attention on the Olympics for debatable cost / benefits.

life force

[thygate]

is this the asteroid that looks like the vampire space ship in life force ?