Yes, but practically speaking, how would that compare, time-wise, to driving from LAX to Santa Monica during rush hour?

Miraculous: yes. Neat: aw hell no!
Anything which is permitted by the laws of the universe is, by definition, NOT miraculous.

With the Schwarzchild radius being that big, how bad would the tidal forces be?

from: http://casa.colorado.edu/~ajsh/schw.shtml
“The tidal force goes as M / r3 at distance r from a black hole of mass M.”
and
“rs = 2 G M / c2″

Since the Schwarzschild radius increases proprotionally to the mass if you double the mass, you double the radius.

If you double your distance from the singularity, your tidal force drops off by a factor of 8 (2^3)

Therefore, for each mass doubling, the tidal force at the event horizon would be quartered. (Tidal force@event horizon: inversely proportional to the square of the mass)

If my mass is correct, I think the tidal force at the Schwarzschild radius of the sun would be 4 million squared times as powerful as at the event horizon of the galactic core? 16 trillion times weaker than at the supermassive black hole…it sure is a good thing for the people living on the surface of the sun that it doesn’t come anywhere near fitting in its Schwarzschild radius!!

Read this please:
http://www.clavius.org/envrad.html
>”The recent Fox TV show, which I saw, is an ingenious and entertaining assemblage of nonsense. The claim that radiation exposure during the Apollo missions would have been fatal to the astronauts is only one example of such nonsense.” — Dr. James Van Allen

That’s right, the Dr. Van Allen who discovered the belts and named them.

Needless to say this is a very simplistic statement. Yes, there is deadly radiation in the Van Allen belts, but the nature of that radiation was known to the Apollo engineers and they were able to make suitable preparations. The principle danger of the Van Allen belts is high-energy protons, which are not that difficult to shield against. And the Apollo navigators plotted a course through the thinnest parts of the belts and arranged for the spacecraft to pass through them quickly, limiting the exposure.

As for “the admission from the government that we still need to build a craft that can safely get man to outerspace”, you haven’t given the context for that statement. Was that really in regard to radiation, or the concerns over the Shuttle External Tank foam shedding and the delicate orbiter tiles and possible damage? That’s a very vague statement that could mean a lot of things, certainly not requiring the conclusion that we haven’t sent people into space.

Even if the statement was in regard to radiation, there is a lot of different radiation concerns to consider. One is the Van Allen belts, but the links provided address that concern. Another is Solar Particle Events – i.e. solar flares. Those provide bursts of strong radiation that if aimed in the correct position could kill humans in space. And no, the Apollo missions weren’t really protected against them. Shocker, but true. Rather, solar particle events are detectable by means of variations in the Sun that occur prior to the event.

http://www.clavius.org/envsun.html

The protection was adequate for the Van Allen belts and normal particle flux from the sun, but probably not enough to protect against a major solar event. It would have indeed been prohibitive to supply the Apollo spacecraft with the shielding necessary to ward off solar event radiation entirely. But with the shielding provided, the astronauts would have been able to withstand a major solar particle event for as long as two hours without receiving a lethal dose.

But protection against radiation isn’t always a matter of piling up enough material to weather the storm. Sometimes it’s a matter of planning and evasion.

A major solar event doesn’t just cut loose without warning. It is possible to observe the “weather” on the sun and predict when a major event will occur. And this is what was done on the Apollo missions. To be sure, the missions were planned months in advance and the forecasting was not that farsighted. But they would have had enough warning to call off the mission should a solar event have started boiling up from the depths of the sun.

Statistical probability was the main protection for the Apollo crews. The forecasters would have been able to rule out major events during the first few days of the mission. And so out of a nine-day mission that might only leave five or six days of vulnerability. The chances of a major solar event occurring within a given five-day period is quite remote, even during periods of exceptional activity.

Also note the difference between a few day long trip to the Moon and a two or more year long trip to Mars. The risks and exposure probabilities are not equivalent.

Phil, another great pic brought to our attention and another great post to go with it. Thanks.

I love it when you wax lyrical about the stars in our sky.

Anyway, Jim, why should something you read somewhere once carry more weight than the pictures and moon rock returned from the moon by the Apollo astronauts?

On “the deadly radiation of space”: http://www.badastronomy.com/bad/tv/foxapollo.html#radiation

And on “identical backgrounds”:
http://www.badastronomy.com/bad/tv/foxapollo.html#backgrounds

Good? Now we can talk.

That may either be a really important observation, or it may be stretching the analogy beyond it’s limits. I think the latter.

Nobby said:
>Someone once told me that they didn’t believe that there was any room in science for faith, he didn’t believe that miricles existed. The birth of stars, the fact that we can appreciate them and marvel at the universe we live in, okay, we can explain them, but does that make them any the less miraculous? Or neat?

Define “miraculous”. I would agree to “amazing”, “wonderful”, “awe-inspiring”, “beautiful”, “thought-provoking”, and probably a dozen other descriptive words, but not “miraculous”.

This is also true of the SMC and several (all?) other dwarf galaxies that are companions to the Milky Way. In fact, it is thought (by some) that some of the larger globular clusters, such as Omega Centauri, may be the cores of dwarf ellipticals that have been stripped of all their outer stars. Eventually, all of the dwarf companions will be absorbed by the MW.

Huh, that’s closer than I would have thought. I wonder how far it would be to the next galactic cluster…

Based on the image I would guess a few things:
- It doesn’t appear to be based on the brightness of the star
- It DOES appear to be based on the color of the star

So, astronomers reading this post, is there a reason we sometimes see flares and sometimes don’t?

Thank you!