Is there any knowledge of when our Sun escaped the nearby spiral arm?

Our Sun is traveling in Solo, away from the probably more
active zone of millions of stars in a neaby spiral arm of our
galaxy. Are there estimates, is there knowledge about the
course of our Sun and when our Sun might have moved out
on its own?

wrote:
Our Sun is traveling in Solo, away from the probably more
active zone of millions of stars in a neaby spiral arm of our
galaxy. Are there estimates, is there knowledge about the
course of our Sun and when our Sun might have moved out
on its own?

Why would you even think that it ever actually did?

"Igor" wrote in news:1166394430.631141.46210@
79g2000cws.googlegroups.com:


wrote:
Our Sun is traveling in Solo, away from the probably more
active zone of millions of stars in a neaby spiral arm of our
galaxy. Are there estimates, is there knowledge about the
course of our Sun and when our Sun might have moved out
on its own?

Why would you even think that it ever actually did?



The spiral arms are pressure waves which don't orbit in the same way as
stars.

Klazmon.

"g" == gb6724 writes:

g Our Sun is traveling in Solo, away from the probably more active
g zone of millions of stars in a neaby spiral arm of our galaxy.

Not sure what you mean by this. There are some nearby star forming
regions, most notably the Sco-Cen association. However, these are
much younger than the Sun.

g Are there estimates, is there knowledge about the course of our Sun
g and when our Sun might have moved out on its own?

The Sun is about 5000 million years old. It takes about 200 million
years to complete one circuit of the Galaxy. Thus, in its lifetime it
has completed about 25 circuits of the Galaxy. Moreover, because of
the presence of other stars and molecular clouds, the orbit of the Sun
is likely to be perturbed (or more technically, it is not on a closed
orbit). Thus, we cannot trace the Sun's path more than a few million
years in the past (or into the future).

In terms of estimating the Sun's escape from its place of formation,
the best we can do is look at other places where stars are forming
currently and estimate how long it will take them to disperse.
Current thought is that the Sun formed in an environment similar to
that seen today in the Orion Nebula, which seem to disperse on time
scales of 100 million years or less (comparable to the time scale on
which planets are thought to form).

Thus, it is likely that the Sun has been solo for most of its
lifetime.

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