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What kind of periodic wobble would our Sol produce from our very-many body solar system? Would it be easy to decipher, or easier to catalog as background noise?

What kind of periodic wobble would our Sol produce from our very-many body solar system? Would it be easy to decipher, or easier to catalog as background noise? Maybe we'll start seeing advances in telescopic technologies and analyses in the years to come -- to pick up on more complex periodic motion of the more complex solar systems.

robryan 14y ago
Just got me thinking, there might be some interesting results from making these kind of observations from say Voyager distance and scaling the resolution of the measurements accordingly to match our results of far more distant system. Not knowledgable enough in the area to know if this would be worth doing.
InclinedPlane 14y ago
If a clone of our Solar System were out in space our chances of detecting it would be extremely low. In order to detect Venus or Earth it would require around a 1 in 100 chance alignment of the orbital plane relative to the observer to be detectable via the transit method. Jupiter would be detectable through radial velocity techniques but it would take a minimum of 12 years to confirm a single orbit and more likely it would take at least 2 orbits for a proper confirmation. And even so it would be a coin flip on whether the orbital plane was aligned properly to be detectable at all. With the increased sensitivity of the new instrumentation used to detect the Alpha Centauri B planet things are improved slightly but still the chances of detecting an Earth-clone via radial velocity aren't that great.
- uvdiv 14y ago
  Where are you getting your chances from? Is there some theoretical limit on the sensitivity of the radial velocity technique, independent of current technology? (edit): This spectrometer is supposed to be capable of detecting an earth-clone, starting around 2016: http://en.wikipedia.org/wiki/ESPRESSO http://en.wikipedia.org/wiki/ESPRESSO This graph shows its predicted sensitivity (green line for a sun-like star), compared to exoplanets previously detected by the same method (gray circles), and solar system planets for reference: http://espresso.astro.up.pt/images/content/science/image012.png http://espresso.astro.up.pt/images/content/science/image012.... http://espresso.astro.up.pt/science.php?show=chapter3 http://espresso.astro.up.pt/science.php?show=chapter3
  - InclinedPlane 14y ago
    You can get a rough estimate of the chances of being able to observe a planet via the transit method by dividing a star's diameter by half of the orbital diameter of the planet (for Earth it's something like a 1:300 chance). For radial velocity the signal detected is proportional to the sine of the orbital inclination. The detectability of Jupiter depends highly on which instruments are being used for observation. My "coin flip" estimate was just a SWAG. If you make use of the best radial velocity detection systems today which have a sensitivity of around 1 m/s and compare that against the maximum 13 m/s radial velocity that Jupiter imparts on the Sun then you end up with much higher chances of detection (80+%) assuming a random relative orbital inclination, but that assumes there aren't any other sources of noise involved.
uvdiv 14y ago
With one star, they teased out nine different planet orbits from its wobble: http://en.wikipedia.org/wiki/HD_10180 http://en.wikipedia.org/wiki/HD_10180

robryan 14y ago

Just got me thinking, there might be some interesting results from making these kind of observations from say Voyager distance and scaling the resolution of the measurements accordingly to match our results of far more distant system. Not knowledgable enough in the area to know if this would be worth doing.

InclinedPlane 14y ago

If a clone of our Solar System were out in space our chances of detecting it would be extremely low. In order to detect Venus or Earth it would require around a 1 in 100 chance alignment of the orbital plane relative to the observer to be detectable via the transit method. Jupiter would be detectable through radial velocity techniques but it would take a minimum of 12 years to confirm a single orbit and more likely it would take at least 2 orbits for a proper confirmation. And even so it would be a coin flip on whether the orbital plane was aligned properly to be detectable at all. With the increased sensitivity of the new instrumentation used to detect the Alpha Centauri B planet things are improved slightly but still the chances of detecting an Earth-clone via radial velocity aren't that great.

uvdiv 14y ago
Where are you getting your chances from? Is there some theoretical limit on the sensitivity of the radial velocity technique, independent of current technology? (edit): This spectrometer is supposed to be capable of detecting an earth-clone, starting around 2016: http://en.wikipedia.org/wiki/ESPRESSO http://en.wikipedia.org/wiki/ESPRESSO This graph shows its predicted sensitivity (green line for a sun-like star), compared to exoplanets previously detected by the same method (gray circles), and solar system planets for reference: http://espresso.astro.up.pt/images/content/science/image012.png http://espresso.astro.up.pt/images/content/science/image012.... http://espresso.astro.up.pt/science.php?show=chapter3 http://espresso.astro.up.pt/science.php?show=chapter3
- InclinedPlane 14y ago
  You can get a rough estimate of the chances of being able to observe a planet via the transit method by dividing a star's diameter by half of the orbital diameter of the planet (for Earth it's something like a 1:300 chance). For radial velocity the signal detected is proportional to the sine of the orbital inclination. The detectability of Jupiter depends highly on which instruments are being used for observation. My "coin flip" estimate was just a SWAG. If you make use of the best radial velocity detection systems today which have a sensitivity of around 1 m/s and compare that against the maximum 13 m/s radial velocity that Jupiter imparts on the Sun then you end up with much higher chances of detection (80+%) assuming a random relative orbital inclination, but that assumes there aren't any other sources of noise involved.

uvdiv 14y ago

With one star, they teased out nine different planet orbits from its wobble: http://en.wikipedia.org/wiki/HD_10180 http://en.wikipedia.org/wiki/HD_10180