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  1. Math --

Another version of @StarMan's answer using only the prolific† vis-viva equation to find the minimum velocity at 1 AU that will graze the Sun:

$$v_{1 AU}^2 = GM_{Sun}\left(\frac{2}{1 AU} - \frac{2}{r_{peri} + r_{apo}} \right)$$

where $GM_{Sun}$ is $1.327 \times 10^{20} \ \text{m}^3 / \text{s}^2$, $a = (r_{peri} + r_{apo})/2$ and $r_{peri}$ is the radius of the Sun.

It's no coincidence that this looks exactly like @ErinAnne's answer as well; there's only so many ways to enforce conservation laws.

The minimum of $v^2$ will be where $r_{apo}$ is also 1 AU ($1.496 \times 10^{11} \ \text{m}$).

With $r_{Sun}=6.957 \times 10^8 \text{m}$ that gives 2865 m/s confirming the other answers.

†https://space.stackexchange.com/search?q=%22vis-viva%22

  1. Physics --

Wouldn't it inevitably spiral down to sun surface even if it was faster than 0 km/s?

That could happen passively if the object had certain peculiar characteristics either by design or by coincidence.

Solar sail

Poynting–Robertson drag

A spinning object orbiting near the Sun could, under some special circumstances slowly spiral into the Sun, but it would usually take a very long time even for a speck of dust, much longer than for a solar sail.

  1. Math --

Another version of @StarMan's answer using only the prolific† vis-viva equation to find the minimum velocity at 1 AU that will graze the Sun:

$$v_{1 AU}^2 = GM_{Sun}\left(\frac{2}{1 AU} - \frac{2}{r_{peri} + r_{apo}} \right)$$

where $GM_{Sun}$ is $1.327 \times 10^{20} \ \text{m}^3 / \text{s}^2$, $a = (r_{peri} + r_{apo})/2$ and $r_{peri}$ is the radius of the Sun.

It's no coincidence that this looks exactly like @ErinAnne's answer as well; there's only so many ways to enforce conservation laws.

The minimum of $v^2$ will be where $r_{apo}$ is also 1 AU ($1.496 \times 10^{11} \ \text{m}$).

With $r_{Sun}=6.957 \times 10^8 \text{m}$ that gives 2865 m/s confirming the other answers.

†https://space.stackexchange.com/search?q=%22vis-viva%22

  1. Physics --

Wouldn't it inevitably spiral down to sun surface even if it was faster than 0 km/s?

That could happen passively if the object had certain peculiar characteristics either by design or by coincidence.

Solar sail

Poynting–Robertson drag

A spinning object could under some special circumstances slowly spiral into the Sun, but it would usually take a very long time even for a speck of dust, much longer than for a solar sail.

  1. Math --

Another version of @StarMan's answer using only the prolific† vis-viva equation to find the minimum velocity at 1 AU that will graze the Sun:

$$v_{1 AU}^2 = GM_{Sun}\left(\frac{2}{1 AU} - \frac{2}{r_{peri} + r_{apo}} \right)$$

where $GM_{Sun}$ is $1.327 \times 10^{20} \ \text{m}^3 / \text{s}^2$, $a = (r_{peri} + r_{apo})/2$ and $r_{peri}$ is the radius of the Sun.

It's no coincidence that this looks exactly like @ErinAnne's answer as well; there's only so many ways to enforce conservation laws.

The minimum of $v^2$ will be where $r_{apo}$ is also 1 AU ($1.496 \times 10^{11} \ \text{m}$).

With $r_{Sun}=6.957 \times 10^8 \text{m}$ that gives 2865 m/s confirming the other answers.

†https://space.stackexchange.com/search?q=%22vis-viva%22

  1. Physics --

Wouldn't it inevitably spiral down to sun surface even if it was faster than 0 km/s?

That could happen passively if the object had certain peculiar characteristics either by design or by coincidence.

Solar sail

Poynting–Robertson drag

A object orbiting near the Sun could, under some special circumstances slowly spiral into the Sun, but it would take a very long time even for a speck of dust, much longer than for a solar sail.

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Source Link
user12102
user12102
  1. Math --

Another version of @StarMan's answer using only the prolific† vis-viva equation to find the minimum velocity at 1 AU that will graze the Sun:

$$v_{1 AU}^2 = GM_{Sun}\left(\frac{2}{1 AU} - \frac{2}{r_{peri} + r_{apo}} \right)$$

where $GM_{Sun}$ is $1.327 \times 10^{20} \ \text{m}^3 / \text{s}^2$, $a = (r_{peri} + r_{apo})/2$ and $r_{peri}$ is the radius of the Sun.

It's no coincidence that this looks exactly like @ErinAnne's answer as well; there's only so many ways to enforce conservation laws.

The minimum of $v^2$ will be where $r_{apo}$ is also 1 AU ($1.496 \times 10^{11} \ \text{m}$).

With $r_{Sun}=6.957 \times 10^8 \text{m}$ that gives 2865 m/s confirming the other answeranswers.

†https://space.stackexchange.com/search?q=%22vis-viva%22

  1. Physics --

Wouldn't it inevitably spiral down to sun surface even if it was faster than 0 km/s?

That could happen passively if the object had certain peculiar characteristics either by design or by coincidence.

Solar sail

Poynting–Robertson drag

A spinning object could under some special circumstances slowly spiral into the Sun, but it would usually take a very long time even for a speck of dust, much longer than for a solar sail.

  1. Math --

Another version of @StarMan's answer using only the prolific† vis-viva equation to find the minimum velocity at 1 AU that will graze the Sun:

$$v_{1 AU}^2 = GM_{Sun}\left(\frac{2}{1 AU} - \frac{2}{r_{peri} + r_{apo}} \right)$$

where $GM_{Sun}$ is $1.327 \times 10^{20} \ \text{m}^3 / \text{s}^2$, $a = (r_{peri} + r_{apo})/2$ and $r_{peri}$ is the radius of the Sun.

It's no coincidence that this looks exactly like @ErinAnne's answer as well; there's only so many ways to enforce conservation laws.

The minimum of $v^2$ will be where $r_{apo}$ is also 1 AU ($1.496 \times 10^{11} \ \text{m}$).

With $r_{Sun}=6.957 \times 10^8 \text{m}$ that gives 2865 m/s confirming the other answer.

†https://space.stackexchange.com/search?q=%22vis-viva%22

  1. Physics --

Wouldn't it inevitably spiral down to sun surface even if it was faster than 0 km/s?

That could happen passively if the object had certain peculiar characteristics either by design or by coincidence.

Solar sail

Poynting–Robertson drag

A spinning object could under some special circumstances slowly spiral into the Sun, but it would usually take a very long time even for a speck of dust, much longer than for a solar sail.

  1. Math --

Another version of @StarMan's answer using only the prolific† vis-viva equation to find the minimum velocity at 1 AU that will graze the Sun:

$$v_{1 AU}^2 = GM_{Sun}\left(\frac{2}{1 AU} - \frac{2}{r_{peri} + r_{apo}} \right)$$

where $GM_{Sun}$ is $1.327 \times 10^{20} \ \text{m}^3 / \text{s}^2$, $a = (r_{peri} + r_{apo})/2$ and $r_{peri}$ is the radius of the Sun.

It's no coincidence that this looks exactly like @ErinAnne's answer as well; there's only so many ways to enforce conservation laws.

The minimum of $v^2$ will be where $r_{apo}$ is also 1 AU ($1.496 \times 10^{11} \ \text{m}$).

With $r_{Sun}=6.957 \times 10^8 \text{m}$ that gives 2865 m/s confirming the other answers.

†https://space.stackexchange.com/search?q=%22vis-viva%22

  1. Physics --

Wouldn't it inevitably spiral down to sun surface even if it was faster than 0 km/s?

That could happen passively if the object had certain peculiar characteristics either by design or by coincidence.

Solar sail

Poynting–Robertson drag

A spinning object could under some special circumstances slowly spiral into the Sun, but it would usually take a very long time even for a speck of dust, much longer than for a solar sail.

added 85 characters in body
Source Link
user12102
user12102
  1. Math --

Another version of @StarMan's answer using only the prolific† vis-viva equation to find the minimum velocity at 1 AU that will graze the Sun:

$$v_{1 AU}^2 = GM_{Sun}\left(\frac{2}{1 AU} - \frac{2}{r_{peri} + r_{apo}} \right)$$

where $GM_{Sun}$ is $1.327 \times 10^{20} \ \text{m}^3 / \text{s}^2$, $a = (r_{peri} + r_{apo})/2$ and $r_{peri}$ is the radius of the Sun.

It's no coincidence that this looks exactly like @ErinAnne's answer as well; there's only so many ways to enforce conservation laws.

The minimum of $v^2$ will be where $r_{apo}$ is also 1 AU ($1.496 \times 10^{11} \ \text{m}$).

With $r_{Sun}=6.957 \times 10^8 \text{m}$ that gives 2865 m/s confirming the other answer.

†https://space.stackexchange.com/search?q=%22vis-viva%22

  1. Physics --

Wouldn't it inevitably spiral down to sun surface even if it was faster than 0 km/s?

That could happen passively if the object had certain peculiar characteristics either by design or by coincidence.

Solar sail

Poynting–Robertson drag

A spinning object could under some special circumstances slowly spiral into the Sun, but it would usually take a very long time even for a speck of dust, much longer than for a solar sail.

  1. Math --

Another version of @StarMan's answer using only the prolific† vis-viva equation to find the minimum velocity at 1 AU that will graze the Sun:

$$v_{1 AU}^2 = GM_{Sun}\left(\frac{2}{1 AU} - \frac{2}{r_{peri} + r_{apo}} \right)$$

where $GM_{Sun}$ is $1.327 \times 10^{20} \ \text{m}^3 / \text{s}^2$, $a = (r_{peri} + r_{apo})/2$ and $r_{peri}$ is the radius of the Sun.

It's no coincidence that this looks exactly like @ErinAnne's answer as well; there's only so many ways to enforce conservation laws.

The minimum of $v^2$ will be where $r_{apo}$ is also 1 AU ($1.496 \times 10^{11} \ \text{m}$).

With $r_{Sun}=6.957 \times 10^8 \text{m}$ that gives 2865 m/s confirming the other answer.

†https://space.stackexchange.com/search?q=%22vis-viva%22

  1. Physics --

Wouldn't it inevitably spiral down to sun surface even if it was faster than 0 km/s?

That could happen passively if the object had certain peculiar characteristics either by design or by coincidence.

Solar sail

Poynting–Robertson drag

A spinning object could under some special circumstances slowly spiral into the Sun, but it would take a very long time even for a speck of dust, much longer than for a solar sail.

  1. Math --

Another version of @StarMan's answer using only the prolific† vis-viva equation to find the minimum velocity at 1 AU that will graze the Sun:

$$v_{1 AU}^2 = GM_{Sun}\left(\frac{2}{1 AU} - \frac{2}{r_{peri} + r_{apo}} \right)$$

where $GM_{Sun}$ is $1.327 \times 10^{20} \ \text{m}^3 / \text{s}^2$, $a = (r_{peri} + r_{apo})/2$ and $r_{peri}$ is the radius of the Sun.

It's no coincidence that this looks exactly like @ErinAnne's answer as well; there's only so many ways to enforce conservation laws.

The minimum of $v^2$ will be where $r_{apo}$ is also 1 AU ($1.496 \times 10^{11} \ \text{m}$).

With $r_{Sun}=6.957 \times 10^8 \text{m}$ that gives 2865 m/s confirming the other answer.

†https://space.stackexchange.com/search?q=%22vis-viva%22

  1. Physics --

Wouldn't it inevitably spiral down to sun surface even if it was faster than 0 km/s?

That could happen passively if the object had certain peculiar characteristics either by design or by coincidence.

Solar sail

Poynting–Robertson drag

A spinning object could under some special circumstances slowly spiral into the Sun, but it would usually take a very long time even for a speck of dust, much longer than for a solar sail.

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user12102
user12102
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user12102
user12102
added 649 characters in body
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user12102
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user12102
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