New Distance to the Orion Nebula, Part Two

Androcles wrote:
"Greg Crinklaw" wrote in message
...
: Androcles wrote:
: Does anyone have an accurate radial velocity or parallax distance
: for beta Persei I can compute with?
:
: http://simbad.u-strasbg.fr/simbad/sim-fid


Thanks for the data overload.

Jerk.

Androcles wrote:
"Greg Crinklaw" wrote in message
...
: Naru wrote:
: Not of you are politicians and realtors looking to put up roadsigns
: and tax ans steal!
:
: Been hitting the bottle again, have yeah?

That or the crack pipe, Greg.
Does anyone have an accurate radial velocity or parallax distance
for beta Persei I can compute with?



I'm fascinated that you appear to think that you would need "radial
velocity OR parallax distance" (my emphasis) to do some computation.
What sort of calculation do you think you can make where you only need
one of these values?

"Chris L Peterson" wrote in message
...
: On Wed, 20 Jun 2007 20:07:10 GMT, "Androcles"
: wrote:
:
: Thanks for the data overload.
:
: Does anyone have an accurate radial velocity or parallax distance
: for beta Persei I can compute with?
:
: I guess you never took to heart the difference between giving a man a
: fish and teaching him to fish g.
:
: There shouldn't be much data overload. Go to the specified link,
: http://simbad.u-strasbg.fr/simbad/sim-fid , and enter "beta persei" in
: the "Identifier" box. The page that comes up has exactly what you asked
: for listed under "Basic data". The radial velocity is 4.0±0.9 km/s (from
: the General Catalog of Stellar Radial Velocities). The parallax is
: 54.14±0.90 mas (from Hipparcos).


Thank you, that was all I wanted.


Period ~70 hours, velocity 4km/s, distance travelled 70 * 3600 * 4 =
1008000 km,
Major axis ~160,000 km, so far inside its own Roche limit it is one star and
not an
eclipsing binary at all. The 4 km/s is proper motion anyway.
http://www.androcles01.pwp.blueyonde...lgol/Algol.htm

Guessing isn't science, however proficient at it you may be. Have you done
much fishing of your own or do you just read books about it? g

Androcles


: _________________________________________________
:
: Chris L Peterson
: Cloudbait Observatory
: http://www.cloudbait.com

On Thu, 21 Jun 2007 09:27:26 GMT, "Androcles"
wrote:

Period ~70 hours, velocity 4km/s, distance travelled 70 * 3600 * 4 =
1008000 km,
Major axis ~160,000 km, so far inside its own Roche limit it is one star and
not an
eclipsing binary at all. The 4 km/s is proper motion anyway.
http://www.androcles01.pwp.blueyonde...lgol/Algol.htm

You'll need to do better calculations than that if you want to support a
crackpot theory (Algol is most certainly eclipsing- something trivially
verified by comparing the optical light curve with the spectroscopic
radial velocity curve).

All three stars in the Algol system have the same velocity through
space, and that velocity has no impact on the dynamics of the multiple
star orbits (anymore than the Sun's motion has an effect on Solar System
dynamics).

And BTW, 4 km/s _is_ the radial velocity of the system with respect to
the Sun, not the proper motion (which is also given in the Simbad data,
if you want to work out the actual velocity vector with respect to the
Sun).

Many multiple stars orbit within their Roche limit. Rigid bodies break
up under those conditions, but stars don't. Stars transfer material,
leading to all sorts of interesting things: cataclysmic variables,
radically different evolutionary ages, and more.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Greg Crinklaw:
At such a distance 200 ly is pretty much within the observational error.
Regardless, I sure wouldn't call a little more than 10% "much closer"
unless I was into writing hyperbolic press releases. I for one will
never understand why some feel astronomy needs all that hyperbole. I
mean, isn't the reality of it all exciting enough?

Not to mention that when one is talking about the size of the Universe,
exaggeration is neither necessary nor possible!

Davoud

--
usenet *at* davidillig dawt com

"Greg Crinklaw" wrote in message
...
: Androcles wrote:
: "Greg Crinklaw" wrote in message
: ...
: : Androcles wrote:
: : Does anyone have an accurate radial velocity or parallax distance
: : for beta Persei I can compute with?
: :
: : http://simbad.u-strasbg.fr/simbad/sim-fid
:
:
: Thanks for the data overload.
:
: Jerk.
Ignorant abusive flaming ****.
*plonk*

"NNTP" wrote in message
...
: Androcles wrote:
: "Greg Crinklaw" wrote in message
: ...
: : Naru wrote:
: : Not of you are politicians and realtors looking to put up roadsigns
: : and tax ans steal!
: :
: : Been hitting the bottle again, have yeah?
:
: That or the crack pipe, Greg.
: Does anyone have an accurate radial velocity or parallax distance
: for beta Persei I can compute with?
:
:
:
: I'm fascinated that you appear to think

Oh really? How flattering! Thank you; although appearances are often
decepetive, perhaps my appearance of thinking is the result of my actually
doing it?

: that you would need "radial
: velocity OR parallax distance" (my emphasis) to do some computation.


: What sort of calculation do you think you can make where you only need
: one of these values?

Quite simple ones, really, such as
time = distance/velocity
from

http://www.fourmilab.ch/etexts/einst...ures/img31.gif

That Einstein bloke almost got it right before he went off half-cocked
trying to build a time machine.

"Chris L Peterson" wrote in message
...
: On Thu, 21 Jun 2007 09:27:26 GMT, "Androcles"
: wrote:
:
: Period ~70 hours, velocity 4km/s, distance travelled 70 * 3600 * 4 =
: 1008000 km,
: Major axis ~160,000 km, so far inside its own Roche limit it is one star
and
: not an
: eclipsing binary at all. The 4 km/s is proper motion anyway.
: http://www.androcles01.pwp.blueyonde...lgol/Algol.htm
:
: You'll need to do better calculations than that if you want to support a
: crackpot theory (Algol is most certainly eclipsing- something trivially
: verified by comparing the optical light curve with the spectroscopic
: radial velocity curve).


You may recall that I asked:
Does anyone have an accurate radial velocity or parallax distance
for beta Persei I can compute with?

The spectroscopic radial velocity curve would be rather nice to have.

Do you happen to have the spectroscopic radial velocity curves for
(supposedly) all three stars, nicely resolved?

The thing is, when I asked for data I got a huge overload of irrelevant
material and was told (by YOU) the radial velocity was 4 km/s. Is not that
from spectroscopic observation, then?


:
: All three stars in the Algol system have the same velocity through
: space, and that velocity has no impact on the dynamics of the multiple
: star orbits (anymore than the Sun's motion has an effect on Solar System
: dynamics).
:
: And BTW, 4 km/s _is_ the radial velocity of the system with respect to
: the Sun, not the proper motion (which is also given in the Simbad data,
: if you want to work out the actual velocity vector with respect to the
: Sun).


Excellent observation, well done. So "proper motion" is motion
relative to
a) the universal frame?
b) Algol's frame?
c) the galactic frame?
d) other?


: Many multiple stars orbit within their Roche limit. Rigid bodies break
: up under those conditions, but stars don't.


Wonderful news, but I didn't ask for that.
So fluids don't break up, but solids do... fascinating, I didn't know that.
Funnily enough, I still don't. And you are the first to introduce the term
"crackpot theory" into the discussion... intriguing.


: Stars transfer material,
: leading to all sorts of interesting things: cataclysmic variables,
: radically different evolutionary ages, and more.

You've photographed this, have you?
It's rather strange, but all anyone else has seen is artist's impressions
of crackpot theories.

Anyway, I'm not really interested in crackpot theories, all I asked
for was data.

Do you happen to have the spectroscopic radial velocity curves for all
three (supposed) stars, nicely resolved?

Empirical data is far more fascinating than crackpot theories, you see...
at least to me. You are welcome to the crackpot theories.

On Thu, 21 Jun 2007 19:00:12 GMT, "Androcles"
wrote:

You may recall that I asked:
Does anyone have an accurate radial velocity or parallax distance
for beta Persei I can compute with?

And you got both.


The spectroscopic radial velocity curve would be rather nice to have.

Do you happen to have the spectroscopic radial velocity curves for
(supposedly) all three stars, nicely resolved?

That isn't what you asked for originally. I don't have the short term
spectroscopic data you are looking for. I'd suggest starting with the
source of the radial velocity data, the General Catalogue of Stellar
Radial Velocities. It should at least provide references to the source
material.


The thing is, when I asked for data I got a huge overload of irrelevant
material and was told (by YOU) the radial velocity was 4 km/s. Is not that
from spectroscopic observation, then?

The radial velocity was determined spectroscopically. The high time
resolution data would show the motion of the respective components,
superimposed on the global motion of the entire system.


Excellent observation, well done. So "proper motion" is motion
relative to
a) the universal frame?
b) Algol's frame?
c) the galactic frame?
d) other?

"Proper motion" is the apparent 2D motion of the object with respect to
our viewpoint. It is normally given in angular units per time for RA and
declination. "Radial motion" is the actual velocity of an object with
respect to our viewpoint, normally given in km/s or redshift. With these
values, and knowing its distance, you can convert the motion of the
object into any frame of reference you like, assuming you can relate
that frame to our own. That could easily be the galactic frame. In this
case, since we are talking about the motion of the entire Algol system,
"Algol's frame" is meaningless. There is no "universal frame", of
course.


: Many multiple stars orbit within their Roche limit. Rigid bodies break
: up under those conditions, but stars don't.

Wonderful news, but I didn't ask for that.
So fluids don't break up, but solids do... fascinating, I didn't know that.

Well you should. A solid body inside the Roche limit of another body is
disrupted by tidal forces. It breaks up very literally, although that
doesn't mean it doesn't largely hang together. A fluid body, however, is
distorted. It may transfer mass, but it certainly doesn't "break up"
anything like a solid body does.


: Stars transfer material,
: leading to all sorts of interesting things: cataclysmic variables,
: radically different evolutionary ages, and more.

You've photographed this, have you?
It's rather strange, but all anyone else has seen is artist's impressions
of crackpot theories.

I have. So have thousands of others. It's what you see in all sorts of
data across many EM bands- photometric and spectroscopic. It's widely
accepted, and it isn't my job, or any other scientist's, to justify.
It's the responsibility of somebody such as yourself to argue why your
theory explains all these things better, and if your webpage is any
example, you have no explanation at all. You suggest that the velocity
of light depends on the velocity of the source, which is utter nonsense,
going against huge amounts of experimental evidence. That sort of
thinking is the very definition of crackpot science.

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Androcles wrote:
"Greg Crinklaw" wrote in message
...
: Androcles wrote:
: "Greg Crinklaw" wrote in message
: ...
: : Androcles wrote:
: : Does anyone have an accurate radial velocity or parallax distance
: : for beta Persei I can compute with?
: :
: : http://simbad.u-strasbg.fr/simbad/sim-fid
:
:
: Thanks for the data overload.
:
: Jerk.
Ignorant abusive flaming ****.
*plonk*

Gee, don't be in such a hurry to thank me!

--
Greg Crinklaw
Astronomical Software Developer
Cloudcroft, New Mexico, USA (33N, 106W, 2700m)

SkyTools: http://www.skyhound.com/cs.html
Observing: http://www.skyhound.com/sh/skyhound.html
Comets: http://www.skyhound.com/sh/comets.html

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