[Closed] Rosetta landing on this Comet, when's it on? And is it live?

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Sounds like they have landed, but may not be secured to the surface, so could still be in the balance....

That could be a problem when they start to drill 🙂

Pic coming though now.... oooh that's not good...

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Everyone seems to have left their workstation unlocked in mission control.

Tsk tsk... this is basic security people. Come on. It's not rocket science.

Perhaps if it was rocket science they'd be good at it 🙂

I think they should have attached a couple of boy scouts with some tent pegs.

@SarcasticRover 7m7 minutes ago
Maybe we don't have to harpoon every comet we land on. Maybe we try negotiating first?

Surface pics should be about due....if it didn't face plant

Can someone explain how it is that we can receive a signal from a a tiny spacecraft stuck to a comet more than 300 million miles away, hurtling through space at 34,000mph, and yet I have to stand at the window to use my mobile in the house?

Use the land line?

Because your phone provider didn't spend billions of pounds on your phone and local cell tower.

Odd that the media seem amazed by the 34000mph thing. I'd say that's one of the least impressive aspects of this mission - orbiting and hopefully staying landed on something with naff all gravity is may more impressive. The success of this and the last mars rover landing are amazing feats of science and engineering.

Use the land line?

It's worse! We don't even get a dial tone*

*(this may or may not be related to the missus dropping a can of beans onto the master socket. I wouldn't like to speculate).

What next for space then?
I think we should try europa and other moons

Do we need person exploration at all?

Europa? ATTEMPT NO LANDING THERE!

"Everyone seems to have left their workstation unlocked in mission control."

You don't want telemetry display functions auto-locking out when you haven't touched the keyboard for a bit. Telecommanding functions have application-level privilege controls based on user role (SPACON). These will be locked-out. It's a physically secure and monitored environment.

C4 reporting the clever bods are having a crisis meting over something at comet rocket control, Obviously they didnt realiise Comet went bust last year.

Would have been more fun if they fitted some sort of gun, rather than the hookey, drilly thingy......

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[quote=thepurist ]Europa? ATTEMPT NO LANDING THERE!
😆

Livecast is back on
http://www.sciencealert.com/watch-comet-landing-live

You don't want telemetry display functions auto-locking out when you haven't touched the keyboard for a bit.

I never said auto lock - you're supposed to lock your workstation yourself when you leave it.

I never said auto lock - you're supposed to lock your workstation yourself when you leave it.

Operational security needs to follow a different model to office based security, besides while these guys may be geniuses in some area, half of them can barely manage to tie there own shoelaces never mind remember a password.

i can tie my shoe laces, but can never remember the passwords.

it's a secure area, never use screensaver or lock.

and whenever possible leave screens with lots of green telemetry on public view (which was a bummer cos the console we'd use for sims where we're purposefully breaking things, was right by the window where you feel like a zoo exhibit, so all the visitors get to see lots of red alarms)

Lol I know it was supposed to be a humorous comment. But it's surprising how many people don't lock their workstations in offices.

GrahamS
Can someone explain how it is that we can receive a signal from a a tiny spacecraft stuck to a comet more than 300 million miles away, hurtling through space at 34,000mph, and yet I have to stand at the window to use my mobile in the house?

Ok, brace yourself, here comes the science:

A mobile phone, or "cell" phone as it used to be called talks to an antenna on a fixed mast. Unfortunately, that mast does not know where your phone is. Broadly speaking that isotropic (and not in reality due to various factors too complex to go into here) antenna is transmitting it's radio waves outwards in a sphere. So, the area of that sphere , relative to the distance(r) you are away from it is 4*pi*r^2. (note the squared term).

Take a typical phone transmitter at around 10w total power output, now divide that power into the area of the transmission sphere. You can see that the total power available for the phone to pick up is tiny.
In fact, even in Line of sight of the tower, without any other blockages, reflections or absorbers, just 1km away, the power is just 80picoWatts/cm^2.

Now, luckily, although the Comet Lander is a LONG way away, we know exactly where it is, and so instead of transmitting our data out in all directions, we can use a High gain antenna, pointed directly at the space craft. And of course, the space craft knows where earth is too, so it will gimball it's antenna to keep it pointing at us. Finally, of course, we don't need to make our space communication antennas "pocket" sized, so we can use a massive area to capture as much of the transmission power as possible:

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[url= http://deepspace.jpl.nasa.gov/ ]DeepSpaceNetwork[/url]

If you have a spare minute, you can "do the sums" for the communication with Voyager 1, which is around 12Billion miles away, and we can still talk to it!!!

Thanks maxtorque. It wasn't really a serious question but the engineering [i]is[/i] interesting.

I still find it amazing. Okay, we know where to point the high gain antenna. But the target is 300 million miles away and isn't very big so surely the slightest gnat's fart at our end means we miss it by tens of thousands of miles?

not just the directional misalignment, but all the interfering sources on earth.
even I find it impressive just working on the LEO stuff.

the interesting engineering is in the optical communications on newer stuff.

andytherocketeer - Member
@SarcasticRover 7m7 minutes ago
Maybe we don't have to harpoon every comet we land on. Maybe we try negotiating first?

LEO stuff is more complex because the Horizon keeps getting in the way!!

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Regarding directionality, then yes, pointing your antenna the right way is of course important, but no antenna is truly collimated, so the beam of radiation spreads out into a cone, and so by the time it gets to the space craft, it's wide, and hence absolute positional accuracy iless critical. Of course, that also spreads out your RF power and needs a higher transmission power, so it's a compromise.

For example, the transmitter on Voyager 1 is just 22 watts, which is roughly the same amount of power as one of the indicator light bulbs in your car! Because it's 18B miles away mind, we need a 70M dia dish to be able to resolve that signal above the noise floor, and when transmitting up to the craft, we need to send with MUCH more power (because it only has a 3.7M dish). Current round trip for those signals is 33hrs.

true about the horizon.
was handy having a satellite to satellite link (LEO to GEO to ground) on the last project, and that way you can have as much as 1 hour of uninterrupted comms in a 100 minute orbit.
sadly next project has the horizon in the way issue again.

where are the pics from the surface???
conspiracy - they are not showing them because its full of REPLICATORS
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For older sci-fi fans, the Philae lander looks like:

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Because its actually:

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IT'S STABLE!!!!

http://www.bbc.com/news/science-environment-30034060

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OOOHH I wonder if theyll find an experimental starship whose phase shifting cloaking device failed?
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This is what you want, on board image just posted on twotter

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http://t.co/EYSlRFjQBb

https://twitter.com/Philae2014/status/532836708661100544

From that link

"The full panoramic from CIVA will be delivered in this afternoon’s press briefing at 13:00 GMT/14:00 CET."

Also, there is some speculation that the first "bounce" when it tried to land was almost 1 km high!

IT'S STABLE!!!!

Some of those Reader's Comments though...

Another huge waste of money to keep poor quality scientists employed on the only trivia they are capable of being involved in .... and they couldn't even do that well ! These people should try working on projects that would have to meet strict business case criteria and suffer the consequences of their failure (like those of us in the real world do) to deserve respect.
...
Really incredible how much money is being wasted on this pie in the sky meaningless expedition into emptiness. It is the triumph of nihilism that the bankrupt EU can still bankroll complete wastage on this scale. It is time we brought into focus how many lives could have been saved in European hospitals for the cost of this space adventure?

[i]*shakes head sadly*[/i]

Fortunately most folk seem to recognise what an amazing achievement it is.

I actually performed 3 landings,15:33, 17:26 & 17:33 UTC.

I did laugh at the rather overexcited lady from the Open University

That wasn't over excitement, that was exactly the right level of excitement given what they've just achieved. It's rather more involved than bending over and balancing a glass on your arse.

remember that the gravitational pull is so weak, that the equivalent of dropping a football and it bouncing a few cm on earth would be a massive distance on a comet.

saw a few of those comments on the beeb, but I refuse to even reply. if you call the cost of a pint spread over 20 years a complete waste of money then fair enough. that's your financial contribution, if you've been a taxpayer for the last 2 decades.

plus it said EU. this is an ESA project. not EU.

@WackoAK - great INFOGRAPHIC 😀 thanks!

fantastic news its down -

can they retry the arm screws or harpoons to try and make it "safe"?

I reckon its landed on its side.