DM + 61 366

[publiusr]

On page 34 of The Starflight Handbook by Mallove and Matloff is an interesting table of nearby stars and their closest approach. The table is from a study by Robert Cesarone from JPL.

Here was a listing that caught my eye:

STAR.....Present Distance from Sun (ly)..Spectral type...Year of closest approach...Distance (ly) of Closest Approach

DM + 61 366..........32.62.............................K5. ...................814,872........................ .................. (0.29)*

* The error in the closest approach distance may exceed 1 light year.

So if I had to pick an object that might pose some threat to Earth--this would be it. I think some later surveys had this stars distance somewhat farther out--but if this thing is to get within .29 ly of Earth--with an error of of one whole light year--perhaps it bears watching--just in case the update measured another star.

This star (DM+61 366) may be listed differently in updates.

[publiusr]

Anyone have more info on this star?

[Lord Jubjub]

Isn't that spectral class M? and .29 ly is about 11,800 AU (~200x of Pluto). How much of a gravitational pull is this going to have on the planetary solar system?

[tjm220]

I tried to enter the info into the rogue star simulator as best as I could but it says nothing drastic will happen with the star so far out. Of course if it does get closer then it's not good. Is this star known by a different name?

[CJSF]

I tried to enter the info into the rogue star simulator as best as I could but it says nothing drastic will happen with the star so far out. Of course if it does get closer then it's not good. Is this star known by a different name?

How massive is DM+61 366?

CJSF

[CJSF]

BTW, you can't put in 11,800 AU in that rogue star web page.

CJSF

[tjm220]

BTW, you can't put in 11,800 AU in that rogue star web page.

CJSF

I know, I used the maximum of 9999 AU and used a mass ranging from .8 to .9 solar for a K type dwarf star.

[CJSF]

BTW, you can't put in 11,800 AU in that rogue star web page.

CJSF

I know, I used the maximum of 9999 AU and used a mass ranging from .8 to .9 solar for a K type dwarf star.

I got an error screen when I put anything greater than 7 AU for the inner planets and greater than 50 AU for the outer planets. Maybe I'm using a different simulator? I had one bookmarked from a couple of years ago. Is the one linked above newer?

CJSF

[tjm220]

BTW, you can't put in 11,800 AU in that rogue star web page.

CJSF

I know, I used the maximum of 9999 AU and used a mass ranging from .8 to .9 solar for a K type dwarf star.

I got an error screen when I put anything greater than 7 AU for the inner planets and greater than 50 AU for the outer planets. Maybe I'm using a different simulator? I had one bookmarked from a couple of years ago. Is the one linked above newer?

CJSF

Sounds like the same one. I got the same error which included the message that close approaches >7 or >50 AU don't drastically alter the inner or outer solar system.

Though this might be a limitation with the simulator code. I entered a 100 solar mass object passing through at 80 AU and got the same error screen. A lot of mass to be considered not drastic.

[publiusr]

This star has a newer name--but I forgot what it was. I was just guessing that the DM reference might have refered to a different star that might have been missed--and its name was confused with a new discovery. I forgot that I had some papers on this star--and it seems that it is farther out now. Of all of the major extra-solar objects to be watching--I'd say this tops the list--due to any influence upon any of the larger kuiper objects (yet to be discovered) that it could perturb.

[Grand Vizier]

This is interesting, though I wonder what a real astronomy thread like this is doing tucked away in the Planet X section. However...

I was musing on whether we were unlucky rather than lucky not to have a close encounter like that in progress right now. A K5 is quite sunlike enough to sustain Earth-like planets, maybe - and imagine how different our calculations on interstellar flight might be if we had such a star just under a third of a light year away - walk in the park. Ah well, at least we're not getting showered with comets...

Found this from the redoubtable Henry Spencer:

Stellar close encounters

More important still, though, is that these predictions are based on
current star catalogs (specifically, the Gliese nearby-stars catalog),
and it is quite likely that on this time scale, there would be other
encounters by currently-uncataloged stars.

[...]

There will probably still be a few surprise
encounters with fast stars (like Barnard's Star) that are currently too
far away for cataloging.

So maybe there's one due any minute :wink:

[publiusr]

The reason I posted the star here was to come up with any kind of peturber that could even remotely cause disturbances like the so-called planet X. The close approach scenario is worth looking at.

A 0.29 ly approach is nothing to sneeze at--esp with 1 ly of error.

[Nereid]

Did you check RECONS?

[Astrobairn]

Did you check RECONS?

Too far for the 100 nearest star list

[Grand Vizier]

The reason I posted the star here was to come up with any kind of peturber that could even remotely cause disturbances like the so-called planet X. The close approach scenario is worth looking at.

A 0.29 ly approach is nothing to sneeze at--esp with 1 ly of error.

No criticism intended at all, publiusr - I didn't know about that 0.29 ly approach and I find the issue fascinating. It's just that I think that you'd get better, more knowledgeable responses about this from General Astronomy. Planet X seems like kind of a backwater these days to me, and I used to hang out here a lot - once upon a time.

[Nereid]

It's HIP 9481, with a measured trig parallax of 4.25 mas, error 0.91 mas (a source, but best to check the HIPPARCOS catalogue directly).

Maybe not such a (distant future) problem after all?

[publiusr]

If this thing lost mass--it may also have lost a planet.

The Planet X forum is the appropriate venue for discussion of remote objects and any effect on Earth--precisely because it is a backwater--and therefore it won't get forgotten about as it would in General Ast.

I do hold major catastrophes to be possible--but not necessarily cyclical. I am worried about a string of extra-solar objects or one time events. They may be very widely spaced--as in a shotgun blast. There may be many dead Earth-like worlds--rogue planets out there. I want to learn more about this star--if star it is.

It is not so much this star itself. If a body cast off by this star (that was already in an unstable orbit about said star) it might pass in front of another star farther away--and be mistaken for a gas giant around that much farther star--when in fact it is a more compact object closer in.

I really want a TAU mission so we can get some craft out of this solar system and have an ultra-wide array.

I just hope the HIP-star and the DM+ listing are in fact the same. Things have a way of getting lost or confused.

[Nereid]

That's mas (milliarcseconds), a unit of parallax, not mass!

You could always check for yourself ... there aren't very many ~7 mag stars in that part of the sky :P

[sakuraba]

So how long until we start to see any of its effects?

[Nereid]

So how long until we start to see any of its effects?

What is "it"?

[sakuraba]

So how long until we start to see any of its effects?

What is "it"?

A rogue star?

[Nereid]

So how long until we start to see any of its effects?

What is "it"?

A rogue star?

Thanks.

However, per the info I dug up, that is unlikely to be HIP 9481 (a.k.a. DM +61 366). At least, not for several million years. :P

(and after that, why should we care?)

[publiusr]

One more reason to support space flight and bugging out.

I wonder if it would be possible to look at DM and nearby stars to see if any of them 'found' a hidden companion. It might be that DM is the sun's companion (Nemesis) and has been moving oh-so-slowly across the heavens and being mistaken for a more distant star that happened to be 'behind' it.

Here is to the hope that Hip 9481 is DM--and that it is in fact more distant.

[sakuraba]

One more reason to support space flight and bugging out.

I wonder if it would be possible to look at DM and nearby stars to see if any of them 'found' a hidden companion. It might be that DM is the sun's companion (Nemesis) and has been moving oh-so-slowly across the heavens and being mistaken for a more distant star that happened to be 'behind' it.

Here is to the hope that Hip 9481 is DM--and that it is in fact more distant.

How close does it seem DM+61 366 seems to be as of now? I haven't been able to find much info googling.

[Nereid]

One more reason to support space flight and bugging out.

I wonder if it would be possible to look at DM and nearby stars to see if any of them 'found' a hidden companion. It might be that DM is the sun's companion (Nemesis) and has been moving oh-so-slowly across the heavens and being mistaken for a more distant star that happened to be 'behind' it.

Here is to the hope that Hip 9481 is DM--and that it is in fact more distant.

How close does it seem DM+61 366 seems to be as of now? I haven't been able to find much info googling.

It's HIP 9481, with a measured trig parallax of 4.25 mas, error 0.91 mas (a source, but best to check the HIPPARCOS catalogue directly).

Try googling 'trigonometric parallax' or 'parsec'; from what you find you can do the calculation yourself easily enough (remember that 'mas' = 'milli-arc second').

[sakuraba]

One more reason to support space flight and bugging out.

I wonder if it would be possible to look at DM and nearby stars to see if any of them 'found' a hidden companion. It might be that DM is the sun's companion (Nemesis) and has been moving oh-so-slowly across the heavens and being mistaken for a more distant star that happened to be 'behind' it.

Here is to the hope that Hip 9481 is DM--and that it is in fact more distant.

How close does it seem DM+61 366 seems to be as of now? I haven't been able to find much info googling.

It's HIP 9481, with a measured trig parallax of 4.25 mas, error 0.91 mas (a source, but best to check the HIPPARCOS catalogue directly).

Try googling 'trigonometric parallax' or 'parsec'; from what you find you can do the calculation yourself easily enough (remember that 'mas' = 'milli-arc second').

Thanks for the tip.

[publiusr]

Anyone have some links or pictures of this star?

[Nereid]

Anyone have some links or pictures of this star?

Are you familiar with Simbad?

If you enter the HIP designation, you can get to a postage stamp from POSS II, centred on the star.

[eburacum45]

With respect, Nereid, your star HIP 9481 appears to be Bonner Durchmusterung +61° 366 , a quite distant star;

there does not seem to be a DM catalogue as such, although this page
http://dml.cmnh.org/1995Dec/msg00842.html
mentions a DM +61366 which was at one time believed to be on a collision course with the Oort cloud.

There are several catalogues called Durchmusterung- is this really the same star?

[Gerbil94]

There are several catalogues called Durchmusterung- is this really the same star?

BD +61 366 has the right spectral type (K5) as listed in the original post, and has the correct DM position code, which should be unique. The other DM catalogues don't cover the correct area (as far as I'm aware, both the CD and CPD durchmusterungs were in the southern sky). BD +61 366 also does have a large radial velocity towards us; it seems it will halve its present distance (given the Hipparcos parallax) to about 100 pc within some millions of years. But I don't believe the data are accurate enough to support anything like a prediction with only a 0.29 ly uncertainty. This one might have to wait for GAIA. At present, it doesn't look close to me.