Starship Asterisk*

I am not sure what Venus presenting it same face during conjunctions with Earth has to do with this topic. This only tells me that Venus is becoming tidally locked to the Sun. Venus and Earth being in close orbits and then separating is a hypothesis that I have not heard about. Venus and Earth curr...

What is the estimated lifetime of a comet ? For a short period comets (orbiting inside the Kuiper Belt) of typical size, several kilometers in diameter, how long does it take to bake or outgass the lighter volatiles and convert it into another asteroid without a coma ? If we know the orbital period...

Thanks, Art, for listing all the reasons for the dimise of comets. The one I was primarily interested in was how long the volatiles survive.

Doug Ettinger
Pittsburgh, PA

I am not sure what Venus presenting it same face during conjunctions with Earth has to do with this topic. This only tells me that Venus is becoming tidally locked to the Sun. Venus and Earth being in close orbits and then separating is a hypothesis that I have not heard about.

Doug Ettinger

I have asked this question in different ways before, but it has been either circumvented or avoided. I only want the straight truth. Can our 80 astronomical unit wide solar system with its various gravity fields within the invariable plane capture dust and gases of IMC's as it passes through them an...

It has been revealed recently to me that the gravity fields of massive objects passing nearby planets could cause the spin axis to tilt or even flip 180 degrees as in the case of Venus. In the case of Uranus the axis is tilted almost 90 degrees on its side. The spin axes of planets are inherently un...

What is the estimated lifetime of a comet ? For a short period comets (orbiting inside the Kuiper Belt) of typical size, several kilometers in diameter, how long does it take to bake or outgass the lighter volatiles and convert it into another asteroid without a coma ? If we know the orbital period ...

Chris, you are your own Wikipedia. I am curious as to why theorists think there may have been an axis flipping ? Could not an off-center collision against its rotational direction have stopped its rotation and slightly reversed it. Perhaps that kind of scenario would have destroyed the planet in the...

Recent observations and studies reveal that there are a large fraction of discovered exoplanets with retrograde orbits (Royal Astronomical Society Press Release). Also, numerous of the "hot Jupiters" are misaligned with the rotation axis of their parent stars. These discoveries do not bode...

I understand that the earth is spinning because of the above The Earth is not spinning because of the hypothesized collision that produced the Moon. Why is mars Spinning? All objects in the Solar System are spinning because they conserve the angular momentum of the nebula from which the system form...

My personal hypothesis deviates from the mainstream. "Gas giant rings do dissapate over time. The rings are replenished by gas and dust that are captured in the outer solar system gravity field from passing interstellar materials. I have a number of issues with this. First, there is no need to...

You may be thinking of Jupiter's and Saturn's resonance creating perturbing forces that slinged some the primary bodies being formed in the asteroid belt region by accretion - leaving behind just small collisional debris. Chris is suggesting that any bodies captured by Jupiter did not collide with e...

By adding more initial conditions I should be able to determine orbital changes with conservation of linear momentum and conservation of kinetic energy equations. A more difficult equation for me that is still required to complete my collision scenario is the case when the impactor strikes the prima...

Thank you very much, alter-ego. If the impact angle, theta, were less than zero, I could simply substract E(k) from the energy conservation equation to obtain the resulting angular velocity. Of course, the solution for w(1) would necessarily be different. Is this correct ? Also, if the primary body ...

The issue is not what is. The issue is the question as to why the Sun should not possess most of the angular momentum since the majority of the mass fell inward to create the Sun. If you contract a spinning mass inward like a spinning skater bringing in their arms to increase spin, why does not the...

Most of the mass for the planetary bodies is in the outer planet, but the Sun by far possesses the most mass of the entire rotating system. But despite the great mass of the Sun, the angular momentum of the Solar System is dominated by the outer planets. It is the four of them that largely determin...

bystander wrote:Most of the angular momentum of the solar system resides in the outer planets because that is where most of the mass is (sans sun).

Most of the mass for the planetary bodies is in the outer planet, but the Sun by far possesses the most mass of the entire rotating system.

DBE

I am just looking for anyone's personal thoughts ( not to end up in any scientific journal ) on why most of the angular momentum of the solar system resides in the outer planets; and, why the Sun spins so slowly after supposely having its own material spiral inward from a disk reaching outward at le...

If there is enough heat from the protorstar disk interior to produce molten interiors and molten materials that have solified, then how did water survive on these smaller bodies without being boiled away into space? The primary heat source for planets and large asteroids is interior radioactive dec...

I am trying to understand the nuances, and you are explaining them quite well. When the planets were first forming they each needed rocky, ferretic cores to begin the larger accretion process. So during the core building stage why did not a core start in the asteroid belt region as well as in the o...

Neufer, thanks for the graphics. This is a great aid to my mathematically deficient brain. Am I to presume that this could be the main method for transfer of angular momentum outward to the planets while they were forming ? Can this type of transfer explain the transfer needed to avoid over-spinnin...

What amazes me is how scientists sometimes flip the coin. On one side of the coin collisional debris if corralled by gravity will last almost forever without being accreted - such as the asteroid belt, the Trojan asteroids, and the outer planet ring systems. On the other side of the coin the collis...

Neufer, thanks for the graphics. This is a great aid to my mathematically deficient brain. Am I to presume that this could be the main method for transfer of angular momentum outward to the planets while they were forming ? Can this type of transfer explain the transfer needed to avoid over-spinning...

Thanks for the reference. dbe

There are more details to be defined before a single-equation solution can had. The densities and post-collision distribution of the masses are needed. A simpler, tractable model could be: 1. The smaller colliding mass hits on the equator (equatorial plane perpendicular to the rotation axis). 2. Th...