Re: Bioastronomy [was Bloated Stars and excess IR] (fwd)

Robert J. Bradbury (
Thu, 19 Aug 1999 15:45:26 -0700 (PDT)

> Amara Graps <> wrote:

> I commented:
> >It is worth remembering, that the astronomers are *presuming* these
> >objects are planets (because that is the only meme their minds currently
> >hold).

Amara said:

> He didn't publish his results (they were null, but he didn't have
> a large search area either) on that particular topic- the data
> on the IR stars were used in some of his other work later on.

Too bad, more astronomers publishing what the have looked for "unsuccessfully" would narrow the search of what others would look for in the future.

> My experience from working with IR astronomers for about 7 years is
> that they _do_ know about things like Dyson spheres, but
> probably not about "giant brains".

It is better not to refer to them as "giant brains", but simply "supercomputers in star-enveloping orbits". This is much less threatening and much harder to argue against. [What technological civilization would not want to build the most powerful computers it was capable of building, given there usefullness in weather analysis, analysis of astronomical data, economic simulations, etc.?] Leave "intelligence/brains" entirely out of the conversation.

> My opinion and experience is that
> IR astronomers are far more "open" than you described, about topics
> like finding intelligence in the Universe in the different forms.

I'll comment with a cautious "maybe". My experience at the Bioastronomy conference (< 10 people out of 200+ showing up at my poster) shows that most bioastronomy/SETI types are either (a) not interested; or (b) reluctant to explore new ideas.

I've reviewed the papers by Valentijn/Werf on the ISO data re: NGC 891 and there isn't even a *hint* of consideration for "alternate explanations". Their data for H2 is quite strong, but they discuss enough anomolies (high H2 temperatures, low CII emissions, variations in the disperse vs. point-source "sources" with increasing distance from the galactic center, etc.), that one is left wondering if in fact their proposed explanation is in fact the simplest? If you can show me side-by-side comparisons of data where astronomers have argued why this is/is-not evidence for/against "dust/gas" aggregates vs. megascale constructs then I will be happy to concede the point. To the best of my knowledge the only active astronomer who believes this and will write about it is Kardashev.

Kardashev has made the point in several papers -- astroengineered megascale objects have a different black-body emission from "dust". I've yet to see a paper where people actually debate this with real data. I will admit this may be primarily due to the restrictions of the available instruments but since I'm not an expert in these fields I'm not really sure that this is accurate.

But when I read an astronomy paper, I'm always asking myself -- are the assumptions in this paper that "intelligent life (a) never evolves or (b) never develops their civilization to the limits of known physics? Almost all of the papers (including those in the SETI literature) contain those implicit assumptions as the "simplest explanation".

> I did some small work with combining star catalogs and IRAS data in
> the early 1990s, and wrote some things about IR excess stars that could be
> useful to some of you interested.

I've looked at this, and it is certainly a good place to start. In my mind the question is matching your start with the gravitational microlensing observations which argue for billions of objects of 0.3-0.5 Msun (which I don't believe are G-class stars).

A fundamental problem in my opinion with our Dyson-Spheres/J-Brain/M-Brain ideas is that we cannot come up with an "optimal" architecture that one could compare with astronomical data.

> (I don't have any discussions on my writeup about the search for other planets
> during the last several years because those discoveries came along after I
> finished my IR astronomy jobs.)

And since planet searches involve spectroscopy line shifts rather than infrared stars or dust observations, this is not unexpected.

But it is nice to hear from someone in the astronomy community that at least some people are open minded about this and are willing to consider the ideas.