'Oumuamua: First extrasolar object spotted?

[Brian G Turner]

And now talk of it being a fragment of a planet wrecked by a binary star system: [1712.01823] 1I/`Oumuamua as a Tidal Disruption Fragment From a Binary Star System

 

[Venusian Broon]

....or it might be an alien craft just passing through :

Astronomers to check interstellar body for signs of alien technology

 

[Ursa major]

What would the Ramafications of that be, I wonder....

 

[Serendipity]

It was measured as 800 metres long and with an aspect ratio of 10:1, its diameter is about 80 metres. So it's one heck os a chunk of rock!

It's also going at speed. And we know it came from outside our solar system. A few thoughts:

1. If this rock can come into our Solar System at speed, others smaller than it can also do that. Some may not be detected until late and although the probably is minuscule, they could on target for Earth. If big enough, they could destroy the Earth. Do we have the capability of detecting such interstellar destroyers in time? [Hint... I don't know the answer, but someone far more expert than I am should look into this.]

2. Its aspect ratio is bizarre, but there is a plausible explanation for such a natural phenomenon, although I would consider it an extremely rare occurrence. We have seen within out Solar System, binary rocks being gravitationally attracted to each other to form dumbbell shapes with aspect ratios of 2:1, maybe 2.5:1. It takes 4, more likely 5, of these dumbbell shapes to combine to give the 10:1 ratio. under what conditions could such an event happen? This sounds like an interesting PhD thesis for some astrophysics student... with the added advantage it may guide the principles of interstellar ship building in the longer term. Again I'm no expert on this...

 

[Harpo]

Others smaller than 80m across could destroy Earth if they're big enough?
Are you suggest asteroids can be "bigger on the inside"?

 

[Parson]

The speed of the rock colliding is also significant and an extra-terrestrial rock would almost have to by definition be moving really, really, fast. I haven't heard if someone has suggested an origin point, but at the speed the rock is going this could very well be the first solar system its invaded and therefore should be able to be tracked.

Edit: Just looked back and saw the article detailing what the current thinking is.

 

[Venusian Broon]

Well, first results in....

Is ‘Oumuamua an alien spacecraft? First scans show no signs of technology

....and they suggest it's just a lump of rock.

Mind you, if it was guided by aliens, perhaps they actually have a Prime directive and they actually act on it. Hence just appearing as a piece of space rubble.

 

[Dave]

If it IS an unmanned alien probe, then we have taken an extremely long time to turn the SETI radio telescopes around on it to send it messages. It has passed by the Earth now (in October) and will be gone soon. Also, should we not have taken advantage of this unusual circumstance to send some unmanned probe of our own there and piggyback a fast ride out of the solar system? It is travelling at a speed 196,000 mph. The fastest probe we have ever made was the New Horizons probe which travelled at a mere 36,000 mph. (Pioneer 10 made 32,400 mph and Voyager about 35,000 mph.) So, it is over five times faster than those probes!

 

[Harpo]

Also, should we not have taken advantage of this unusual circumstance to send some unmanned probe of our own there and piggyback a fast ride out of the solar system? It is travelling at a speed 196,000 mph. The fastest probe we have ever made was the New Horizons probe which travelled at a mere 36,000 mph. (Pioneer 10 made 32,400 mph and Voyager about 35,000 mph.) So, it is over five times faster than those probes!

It was only spotted eight weeks ago, and for half that time we weren't certain that it was from outside.

 

[Venusian Broon]

I suspect by the time a probe could be rustled together from scratch the object will be far out on its way out of the system and (I guess) out of range of any current propulsion tech!

 

[Dave]

You're both right, of course! Maybe in future we can have one standing by, ready.

Wasn't the Space Shuttle partly about having a spacecraft available with a very short turnaround? The ***** ************** recently announced that they would "send Americans astronauts back to the Moon, and beyond." I can't see much chance of that if they don't currently have the means to rustle together even a probe.

Also, the plots of Deep Impact, Armageddon and Space Cowboys will all need to be re-written. We will still send nuclear missiles to destroy the asteroid before it hits the Earth, but we just need to delay it for a few years first while we build the delivery spacecraft. That gives us plenty of time to train young astronauts, so we won't need any of those old guys anymore. Buzz Aldrin (87 years-old) can rest easy again.

 

[Venusian Broon]

There must be an emergency spacecraft that could be thrown together at a moments notice - I'd guess some old reliable Russian one - to rescue/help the people in the International space station...but that's just in low orbit around the earth.

I think the problem is that as soon as you try and go further than that, even - say - getting to the moon, which is pretty close, then you are really having to design a craft specifically for the mission requirements, so it becomes very much bespoke. And that would require a great deal of design and testing.

Then you've got to get the funds first - so that requires a bit of lobbying.

Having said all that, it surely depends on what opportunities come up. Imagine if that radio sweep of the object had picked up the faintest whiff of artificiality? I guess even Trump would throw billions of dollars at the problem of 'immediately' launching a probe to investigate.

 

[Parson]

I'm not a rocket scientist, but I doubt that there is any technology available to us today, especially on short notice, that could run down an object moving away at 196,000 mph.

 

[Ursa major]

I'm still not sure about how we know the object is covered in spots....


*cough*

 

[Harpo]

That's easy - the fastest animal is covered in spots, therefore the fastest aliens must also be so

 

[Cathbad]

Does it have the measles?

 

[Vertigo]

I'm not a rocket scientist, but I doubt that there is any technology available to us today, especially on short notice, that could run down an object moving away at 196,000 mph.

This was my first thought as well. The difference in the speeds mean that it would be pretty much impossible for the probe to hitch a ride without being utterly destroyed in the process.

Shame...

 

[Serendipity]

Oumuamua is covered in a thick crust of carbon-rich gunk to give it its reddish colour - see Interstellar object ‘Oumuamua covered in 'thick crust of carbon-rich gunk' - interesting because the gunk was 'frozen on', Oumuamua did not generate a tail on its close encounter with the Sun, the kind of thing we associate with comets passing close to the Sun.This detail disturbing is.

 

[Dave]

The difference in the speeds mean that it would be pretty much impossible for the probe to hitch a ride without being utterly destroyed in the process.

I was thinking of something crash-landing, but at 5x the speed and at such a very high speed you are, of course, correct. In addition, the last time we tried to crash on a comet it didn't work so well. Also, it has already passed us and could not be caught anyway. So, all in all, we don't have the technology. It is a pity though.

 

[Vertigo]

Oumuamua is covered in a thick crust of carbon-rich gunk to give it its reddish colour - see Interstellar object ‘Oumuamua covered in 'thick crust of carbon-rich gunk' - interesting because the gunk was 'frozen on', Oumuamua did not generate a tail on its close encounter with the Sun, the kind of thing we associate with comets passing close to the Sun.This detail disturbing is.

Might the reason for this be its very high speed resulting in less time for stuff to evaporate off? Or maybe it's down to the material; the tail of comets is, I think, mostly water whereas this is 'carbon rich gunk' so very different composition.