Dyson Sphere, Drake and Kepler

clear thinking

This is starting to make a few headlines.

It is possible that an observation by Kepler has spotted a dyson sphere.

Kepler is running off half its guidance motors, if I recall, and if this discovery produces more evidence it would confirm life in our galaxy elsewhere than our solar system.

There are approx 1,000 exoplanets confirmed and thousands more candidate exoplanets, so there are comparatives which make this very exciting as it must be pretty compelling evidence compared to all the other observations.

the links below also give a bit of details of Kepler and Fergal Mullally who gave a great presentation at the science gallery about his work at NASA, well worth a read.

It'll also be interesting in verifying the drake equation given that Kepler is only looking at 0.25% of the sky, and can only observe about 1% of transits - albeit the closer to completion a dyson sphere is the more observable it would become.

https://www.youtube.com/watch?v=vB0Aw1ThIes

https://dublin.sciencegallery.com/events/2012/07/planet-hunting-kepler-nasas-fergal-mullally-joins-sfi-speaker-series

http://www.independent.co.uk/news/science/giant-alien-megastructure-found-in-space-what-is-dyson-sphere-and-what-else-could-we-have-found-a6695556.html

http://www.popsci.com/alien-megastructures-how-astronomers-plan-to-investigate

clear thinking

The actual paper:

http://arxiv.org/pdf/1509.03622v1.pdf

And anoter paper on what we should be looking for http://arxiv.org/pdf/1510.04606v1.pdf

Dan_Solo

What I don't get is how any alien race that close to us hasn't been bombarding us with messages for centuries?

clear thinking

Dan_Solo wrote: »

What I don't get is how any alien race that close to us hasn't been bombarding us with messages for centuries?

They may have observed us in the same way kepler is looking for goldilocks planets.

There's only 150 years of electronic messaging, and radio and TV has been even shorter, so they might not have bothered as they wont have got any signals from us.

There's a view out there that if you risk contact (ignoring the 2,800 year cycle for messaging) that you might be inviting aliens to visit, not necessarily a great idea if they have superior technology.

It may even be possible the dyson modules could be set up in prime number arrangements that we just have not yet observed, so in theory the planet sized transit modules could be in clumps of 1, 2, 3, 5, 7 etc to give a lighthouse type signal.

Dan_Solo

clear thinking wrote: »

They may have observed us in the same way kepler is looking for goldilocks planets.

There's only 150 years of electronic messaging, and radio and TV has been even shorter, so they might not have bothered as they wont have got any signals from us.

Well I was more thinking that any civilization that has constructed a Dyson sphere must be centuries ahead of us technologically and would have recognised earth as a potentially life supported planet long ago.
Is there a guess at how far in our future any possible Dyson sphere could be? 1000? I'm just afraid in this case there's some other "mundane" matter shedding event being hyped up.

clear thinking

Dan_Solo wrote: »

Well I was more thinking that any civilization that has constructed a Dyson sphere must be centuries ahead of us technologically and would have recognised earth as a potentially life supported planet long ago.
Is there a guess at how far in our future any possible Dyson sphere could be? 1000? I'm just afraid in this case there's some other "mundane" matter shedding event being hyped up.

You are more than likely right, but it will be useful to get explanations if it is natural - so if there are similar observations n future they can be identified as natural, and therefore easier to spot a real dyson construction.

The wikipedia pages are pretty good on explanations, but you are probably talking tens of thousands of years to get to an observable scale and the tech needed to transimit energy back to the host planet effectively.

And for the Civilisation to have managed to not nuke itself to oblivion before that level of tech is achieved.

jaykay74

Dan_Solo wrote: »

What I don't get is how any alien race that close to us hasn't been bombarding us with messages for centuries?

If an alien race has the ability to find intelligent life I would think we are not that interesting (the assumption being that the universe is teeming with life). Do you engage with every ant you pass along the road ? Its unlikely to just us and some super advanced alien race.

Keplar240B

If nuclear fusion exists why bother building a dyson sphere which if i understand is a big solar panel

Manach

Given my understanding of the Drake equation but also given the hostility of the natural environs to the creation of advanced life, the chances of such being a construct (in spite of my channelling the wishes of Larry Niven) would be slight - IMHO.

Nate--IRL--

Keplar240B wrote: »

If nuclear fusion exists why bother building a dyson sphere which if i understand is a big solar panel

Because for fusion you need fuel - why not use the biggest fusion reactor and fuel source there is?

Nate

_Tombstone_

Now, some astronomers are saying it might just be caused by a rapidly spinning and irregularly shaped star.

In this scenario, we have a star that is spinning fast enough to become oblate; i.e., it has a larger radius at the equator than it does at the poles, producing higher temperatures and ‘brightening’ at the poles, while the equator is consequently darkened. The transits of a planet in this scenario can produce asymmetrical light curves, a process the Wright paper notes, and one that [astronomer Michael] Million began to discuss as early as the 17th in the comments here [at Centauri Dreams]. That discussion was picked up in Did the Kepler space telescope discover alien megastructures? The mystery of Tabby’s star solved, which appeared in a blog called Desdemona Despair. The author sees the case as clear-cut: “There are four discrete events in the Kepler data for KIC 8462852, and planetary transits across a gravity-darkened disk are plausible causes for all of them.”

Meanwhile, Centauri Dreams reader Jim Galasyn uncovered a paper by a team led by Shoya Kamiaka (University of Tokyo) studying gravity darkening of the light curves for the transiting system PTFO 8-8695, also studied by Barnes, which involves a ‘hot Jupiter’ orbiting a rapidly rotating pre-main-sequence star. Gravity darkening appears to be very much in play, and we can, as the Desdemona Despair blog does, cite the Barnes paper: “An oblique transit path across a gravity-darkened, oblate star leads to the long transit duration and asymmetric lightcurve evident in the photometric data [for the PTFO 8-8695 system].”

http://gizmodo.com/that-so-called-alien-megastructure-could-just-be-a-dist-1738979646

_Tombstone_

Looking For Deliberate Radio Signals From KIC 8462852

SETI ain't finding any.

nokia69

Nate--IRL-- wrote: »

Because for fusion you need fuel - why not use the biggest fusion reactor and fuel source there is?

Nate

yeah but given the size and the time it would take to build the sphere there must be a easier sources of fuel to be found

so IMO any alien civilization that had the tech to build a Dyson Sphere never would

Nate--IRL--

nokia69 wrote: »

yeah but given the size and the time it would take to build the sphere there must be a easier sources of fuel to be found

so IMO any alien civilization that had the tech to build a Dyson Sphere never would

You might use something like Jupiter for fuel i suppose - how to mine it to get the same scale of output as the sun? Also no amount of reactors will come close to one millionth the output of the sun.

Assume if you will, that all other sources of fusion fuel and the growth potential in how to use it have been exhausted - the Dyson Sphere is the final, ultimate, step to get more energy.

You could cover a planet in fusion reactors and still no be anywhere near the output a Dyson sphere would collect.

Nate

cowboyBuilder

AFAIK a Dyson sphere is not just a solar panel, but the whole Sphere is terraformed land with an atmosphere climate etc ... so imagine the surface area of a sphere around a star like ours with a Sun-Earth radius .... phenomenal .... tens of millenia away tech wise.

But fascinating stuff.

clear thinking

If you get into a civilisations in its own solar system lasting 100k+ years you would exhaust energy resources on one planet very quickly.

I hadn't come across a theory on habitable spheres - Id imagine you'd be zero-G and therefore it is not possible.

Aside from capturing solar energy there are few other options, syphoning gas giants sounds harder than doing a/the sphere option.

Radio is nearly obsolete here after a mere +-100 years, it may be difficult to find a window in time to find it anywhere else. Equally, the civilisation could be extinct and this is a case on interstellar archaeology.

cowboyBuilder

clear thinking wrote: »

... interstellar archaeology.

I love it

_Tombstone_

Newest paper on it finds evidence that it's a swarm of comets around it.

https://www.nasa.gov/feature/jpl/strange-star-likely-swarmed-by-comets

Dan_Solo

clear thinking wrote: »

Radio is nearly obsolete here after a mere +-100 years, it may be difficult to find a window in time to find it anywhere else. Equally, the civilisation could be extinct and this is a case on interstellar archaeology.

I doubt if it's likely a civilisation would be 100,000 years old and be capable of constructing a Dyson Sphere would not have some sort of interstellar travel projects. Unlikely the entire race would be extinct.

clear thinking

Just saying its a possiblity!

The thing does seem to be a natural occurance based on some recent studies of it, but the upside still is that it will help science in identifying these things.

_Tombstone_

They've found another star behaving the same way, EPIC 204278916, now they reckon they're just a new "dirty young planetary system."