news.com.au solar system size fail

[Somnium]

when describing a pair of orbiting black holes on a collision course on news.com.au the reporter said

"The distance between them has been estimated at about one million light years away or the diameter of our solar system."

i checked other sources and they are calling the distance around 1 light week. if this was a proper science journalist then i am sure such an error wouldn't have slipped through the cracks

[billdan]

That's definitely bad reporting.
But what is the diameter of the solar system?

Does it stop at the heliopause where the solar wind meets interstellar space which is 100AU or approx 13 light hours giving the diameter of the solar system 26 light hours.

Or does it stop at the edge of the Oort cloud which is 1 light year from the sun to its edge.

Bill

[xelasnave]

You would think being presented with an orbit of a million light years would ring an alarm for a start.
Second in my mind I get a flash suggesting the solar system extends halfway to M31 and overshadowing our galaxy greatly.
The Oort cloud is a hypothetical proposition as far as I can tell. I don't know what evidence exists to support it's presence. Talked about as a reality is there any observational evidence . I don't know there is any evidence..is there any?
I think defining the solar system as extending to the heliosphere would be sound as this is a boundary between the influence of the sun and interstellar space...but then there is gravity of the sun..does it count past the heliosphere ..

[Somnium]

the Oort cloud's existence is inferred from long period comets which don't tend to come from the ecliptic. they are essentially random in their orbit and are likely to be making their first foray into the inner solar system. so yes, no direct observation but it is far from being a wild hypothesis

[xelasnave]

I don't think it is a wild idea but wonder if it is a reality after all the idea suggests (to me) that there is an outter shell to the solar system some 2 light years dia, and possibly 6 light years dia which seems rather large...nevertheless observation Would be nice (for me)
I have wondered if it is not there what such may imply.
For one our understanding of comets would be different..even perhaps how the solar system evolved.
Babbling again.
Mmmmm sorry

[N1]

Many think that's a suitable definition. In any case I expect it's an upper limit regardless of what other approaches might be taken. Even the largest models would have to be substantially less than 2ly regardless of how you define it, as that same definition would place you within the influence of the Alpha Cen system if you went out much further. 3 stars, two of which are somewhat sun like versus one, suggesting you're in their backyard long before the halfway point between us and them.

Unless it is somehow revealed that we are in fact part of that system or otherwise interacting with them, which would be cool.

Edit: Apparently there is some literature regarding Alpha Cen's influence on the Oort Cloud, starts on page 6. 100,000 potentially Earth-impacting comets - bring it on! :P
(http://adsabs.harvard.edu/abs/1994QJRAS..35....1M)

[AussieTrooper]

I'd say 2012 VP113 is getting there. Aphelion is about 450AU, and a 4000 year orbit.
It would be the largest object out that far that we know of yet.

[Somnium]

oh boy, now the New York Post gets into the act. In an article banging on about the pseudo-science of astrology they said

"The last time a planet had any affect on us, Helfand says, is when a chunk of rock that would eventually become Mars crashed into Earth and created the moon 4.5 billion years ago."

i think they meant a Mars sized object, Theia did not form Mars. Am i expecting too much from reporters for this basic fact checking? it really concerns me about the other types of mistakes they make that i can't pick out off the top of my head ... scary

[AussieTrooper]

Well, kudos for at least getting stuck into the astrology scam.