ralph

2009-Jan-01, 09:59 PM

Hi,

I started this bit of research with an idea that the earths speed around the sun must be changing. I may be wrong here, but with all the variables, I don't see how.

The rough speed is 30 km/sec, taking the year-long mean period, and dividing by the mean distance.

That's the easy answer. I'm looking for detailed research into this, but haven't found it yet.

Reading all the answers more closely, I wondered about the data that lead to those answers.

They all use a steady mass for both the earth and sun. I have problems here.

The earth is recieving more mass all the time, from outside sources, such as dust and meteorites, to the tone of tonnes per year.

I know this is miniscule, compared to the mass of the earth, but it must therefore be increasing.

Is the earth losing mass, and which is greater? (and by how much)

Just on this logic, I'd believe it's gaining.

That's question #1. -and two, and three, I guess.

The sun is converting billions of tonnes of hydrogen to helium every second, and must be losing mass, even with all the mass that crashes into it from the rest of the galaxy.

So how much mass is the sun losing, and at what rate?

That's the next question.

Between these two, it would have to affect the earths orbit, both in distance and speed.

Any references?

I started this bit of research with an idea that the earths speed around the sun must be changing. I may be wrong here, but with all the variables, I don't see how.

The rough speed is 30 km/sec, taking the year-long mean period, and dividing by the mean distance.

That's the easy answer. I'm looking for detailed research into this, but haven't found it yet.

Reading all the answers more closely, I wondered about the data that lead to those answers.

They all use a steady mass for both the earth and sun. I have problems here.

The earth is recieving more mass all the time, from outside sources, such as dust and meteorites, to the tone of tonnes per year.

I know this is miniscule, compared to the mass of the earth, but it must therefore be increasing.

Is the earth losing mass, and which is greater? (and by how much)

Just on this logic, I'd believe it's gaining.

That's question #1. -and two, and three, I guess.

The sun is converting billions of tonnes of hydrogen to helium every second, and must be losing mass, even with all the mass that crashes into it from the rest of the galaxy.

So how much mass is the sun losing, and at what rate?

That's the next question.

Between these two, it would have to affect the earths orbit, both in distance and speed.

Any references?