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Fraser
2004-Jul-09, 04:48 PM
SUMMARY: The twin Voyager spacecraft, located at the edge of the solar system, have detected the effects of the most powerful solar storm ever detected, that blasted off the Sun in October/November, 2003. Thanks to a fleet of spacecraft, including Cassini, Mars Odyssey and the Voyagers, NASA scientists have been able to get a comprehensive view of how storms travel across the solar system. They hope that when the storm crashes into interstellar gas in a few more months, it will emanate radio waves detectable here on Earth.

What do you think about this story? Post your comments below.

antoniseb
2004-Jul-09, 04:52 PM
It gives you an idea just how far away Voyager One is right now, knowing that it takes a day or two for these blasts to get to the Earth, and it took eight or nine months to get out to Voyager.

It will be interesting to see if we do get some radio signal from the bounce-back when it hits the interstellar medium, and when that happens.

Solar Powered Sailor
2004-Jul-09, 05:44 PM
it's quiet amazing our little Sun. the emission of all that power, quiet remarkable that even the Cassini and Voyagers can feel the power of how storms travel across the solar system

Guest
2004-Jul-09, 08:13 PM
The sun really isn't little, it is in the top 10 percent in size of all stars put together. Of course it is no Betelgeuse or Rho Cassiopea either. This does show you how hazardous working in space can be. In the same light it show you how important it is to have a good radiation shield within a few minutes reach of whereever you are in space.

om@umr.edu
2004-Jul-10, 12:28 AM
Thanks, Fraser, for an interesting story and a reminder of the energy released by solar storms.

As noted in the feature article in the current issue of National Geographic,

-1.- Solar storms have a great impact on mankind, and

-2.- Solar storms and solar magnetic fields are not understood.

With kind regards,

Oliver
http://www.umr.edu/~om

Guest_Mark
2004-Jul-11, 06:40 AM
Thank you for a most interesting report. I had no idea that the Voyagers were still being utilized. Today was the first time I read universetoday.com and this story made me quickly add it too my list of regular reading. Thx!

James Friesen
2004-Jul-12, 01:26 AM
Check out the Voyager website. It is amazing, both spacecraft have ample power and even thrust gas left to operate until approx 2020!!! The capabilities of each one have and will continue to decline until there is not enough power to operate any single instrument. They actually execute a spin of each spacecraft to calibrate the magnetic sensor, and they do it like six times a year! These missions are by no means dead. The cameras may be dormant, but the ships are very much alive!


Voyager - JPL website (http://voyager.jpl.nasa.gov/index.html)

Discussion of long term mission (http://voyager.jpl.nasa.gov/science/index.html)

Hoore500
2004-Jul-12, 04:24 AM
I cannot follow all this stuff which is certainly not going to keep me from putting my one years old question on this board especially while at OU London (where disterasterous Beagle 2 comes from) I don't come to the point since the leak out of my cable.

I don't know what Friedman's intention is or was with his Voyager missions (I suppose search for alien life), but I read they have a velocity of maybe 13 and 17 km/s or a bit more? The exact amount doesn't matter that much, it is only that the Sun's escape velocity must be something like 800 km/s. Those Voyagers I suppose they always get further away from the Sun, so there is progress (but they don't accelerate) , then how can they escape the Sun? Maybe it is too much work to explain, but can't at least one being tell me he understands it? I'm living in a complete shutting up of my surroundings for one year now.

It's really to complicated for asking at OU L., I can hardly reach them, I can surf about half an hour a day, and after that ... But in fact I don't pay. I also urgently have to put some questions about the Moon dust overthere.

Please. But just don't waist energy, in a while my message may be gone. Bye bye Fraser, thanks for cleaning your board, but you can at least let me know that I don't do senseless search for my dirty messages.
And else it's the board itself.

antoniseb
2004-Jul-12, 12:06 PM
Originally posted by Hoore500@Jul 12 2004, 04:24 AM
they have a velocity of maybe 13 and 17 km/s or a bit more? The exact amount doesn't matter that much, it is only that the Sun's escape velocity must be something like 800 km/s. Those Voyagers I suppose they always get further away from the Sun, so there is progress (but they don't accelerate) , then how can they escape the Sun?
The escape velocity from the sun's surface is very different from the escape velocity from the Sun at Earth's distance, or especially out beyond Neptune at 90AU where Voyager is now. The escape velocity from the sun at the Earth's distance is about 42 Km/sec, with the Earth already supplying about 29 Km/sec of that [once you escape Earth's gravity]. Any velocity above that plus velocity gained from passing other planets will be velocity that a craft still has as it leaves the solar system.

Similarly, the escape velocity from the Earth is about 40 Km/sec but a craft leaving Earth orbit from the moon already has most of the required energy, and only needs an extra few km/sec to escape Earth, once it escapes the moon.

Hoore500
2004-Jul-12, 07:43 PM
You have to write it down a little bit clearer, because sometimes I don't understand what you mean. So I thought the escape velocity of the Earth is 11,18 km/s. What you tell about the Moon I don't see what it has to do with it, unless Voyager2 made a turn around the Moon.
I think escape velocity of a heaven body is one fixed amount and that you don't have to try changing that. In London OU they say that the Earthish velocity is 11,18km/s FROM THE SURFACE OF THE EARTH, well for me is that high in the sky at 35.590km, where geostationary satellites hang.

About the increasing of the velocity after a fly by okay, but last year I read the Planetary Society's report about the Voyagers, well they make appear that both the Voyagers' velocities stay about the same during all those years. Can you explain what happens during a fly by? I don't understand very well you can importantly increase a craft's velocity by a fly by because what it wins in energy because of the attracking before, it also loses when it has passed the planet, because it still attracks. You see?

Thanks in advance. Oh yes, and admit a solar sail ship when it returns to Earth (e.g. from Titan) rather can move because of the attraction or gravity of the Sun then by tacking against the solar beams.

In fact I know very few physics, even simple dynamics of Newton. I really don't see how a craft can accelerate after a fly by.

antoniseb
2004-Jul-12, 09:41 PM
Originally posted by Hoore500@Jul 12 2004, 07:43 PM
I thought the escape velocity of the Earth is 11,18 km/s.
You are right about that. I made a mistake by writing without looking it up. My recollection was 42 Km/sec, but it is 42,000 Km/hour which is about 11 Km/sec.

I think you have some misconceptions about escape velocity, but I couldn't be certain given your command of English.

Concerning what I said about the Moon, I will remember that your English language and science skills are weak, and will give you simple answers in the future.

Concerning gaining speed in a fly-by it is not so simple that I am comfortable explaining to you given that you thought my other explanations were too complicated.

Hoore500
2004-Jul-13, 05:59 AM
Deleted for content

Manchurian Taikonaut
2004-Jul-13, 12:53 PM
What is your question ? Yes the Beagle was a mess. However forget about this Beagle 2 for a while, I mean lots of Countries and Space agenices have made errors, Russian designs which went kaput, the probes which failed from NASA, the mistake by the ESA craft, the early Chinese stuff that blew up instead of going up . What is the thing that you are asking?

How did the Voyager travel out at the edge of the solar system to where these solar flares are?

And what happened to the Voyagers velocities , and why was this speed possible ?



Well its kind of a long question but i'll try and put it in simple terms

But first think about speed and think about energy. Here was one statement : matter-energy can not be created nor destroyed, however they say Matter also can be transformed to energy, and energy can be transferred into matter. Say for instance there are other ways to look at it, like in an orbit, conservation of energy can be used to explain Kepler's second law. When the distance to the Sun decreases, the potential energy decreases as well. This must be compensated for with an increase in kinetic energy, which means the orbital velocity must be fastest when closest to the Sun. What happens to forces acting, the larger the force is, the larger the accelerations.

Inside a circular orbit of objects with the distance a constant, the kinetic energy is 1/2 the potemtial energy. If the kinetic energy is large enough, it can overcome the gravitational attraction and the object can escape the gravitational pull. This happens when the total energy is zero, or when the kinetic energy is as large as the potential energy. You can use this fact to calculate the velocity necessary to escape from orbit. This is the escape velocity required to send astronauts to the Moon, send the spacecraft to Venus and Mars, or send the Voyager spacecraft out of the Solar system. Other Orbits can be used to describe the paths a parabolic orbit describes an object which is marginally bound. Some other types of ideas like energy conservation and conversion from one form to another are extremely important concepts in physics and astronomy


I could go on further to describe all the various laws describing force and velocity and energy, which will help you understand how stuff went to Venus or how craft were sent to Mars.

but I'll have a go at it in a more simple manner

you don't get energy for nothing, it isn't totally free :)

Imagine you have a craft and you want to send it speeding out to Neptune by doing a sling shot around Mars, the craft will take energy from the Martian planet and the planet will spin slower but because Mars is very big the change will be so insignificant it will be as if nothing changed but the craft will move faster. If you think more about this more and read more on it you'll understand how the Voyagers were sent out to the edge of the solar system.