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NASA Solar Probe Blasts Toward Rendezvous With Sun
coondoggie writes "NASA this morning used a United Launch Alliance Atlas rocket to blast its 6,800lb Solar Dynamics Observatory into an orbit 22,300 miles above Earth. The $808 million spacecraft will ultimately study the Sun and send back what NASA called a prodigious rush of pictures about sunspots, solar flares and a variety of other never-before-seen solar events. The idea is to get a better idea of how the Sun works and let scientists better forecast the space weather to offer earlier warnings to protect astronauts and satellites, NASA said."
I think that I will go outside and rendezvous with the Sun too.
However, even if it isn't going much closer to the Sun than my back yard, it is in a cool orbit.
SDO is a sun-pointing semi-autonomous spacecraft that will allow nearly continuous observations of the Sun with a continuous science data downlink rate of 130 Megabits per second (Mbps). The spacecraft is 4.5 meters high and over 2 meters on each side, weighing a total of 3100 kg (fuel included). SDO's inclined geosynchronous orbit was chosen to allow continuous observations of the Sun and enable its exceptionally high data rate through the use of a single dedicated ground station.
So, it is in a geostationary orbit with the major advantage of the L1 Lagrange point (continuous observations) but requiring less fuel to reach, less power to communicate, and only one ground station (a L1 observatory needs 3, or sufficient on-board recording). That sounds like a major win for this new orbit, which I predict will be used more in the future.
With this orbit, it might also be able to get some cool pictures of Lunar eclipses, which SOHO (at the L1 Lagrange point) can never do.
It's in orbit of earth. It's not going anywhere near the sun, at least not much nearer than earth.
Not a sentence!
These are *not* in situ instruments like what's on ACE, where it has to get hit to be known.
Part of SDO's mission in is space weather prediction -- trying to identify active regions that are likely to flare or throw off a CME, and thus provide more advanced warning so spacecraft can take precautions.
Disclaimer : I'm affiliated with one of the sites that's going to be distributing SDO data.
Build it, and they will come^Hplain.
My understanding is the flare does not move at the speed of light - it is plasma not photons. I could be wrong ...
Not really - flare particles ("coronal mass ejections") travel at about 400 km/sec, much less than the speed of light, giving plenty of time for predictions if you can see the flare erupt on the Sun.
Nothing travels faster than the speed of light. So when this satellite learns of the big flare, it has already hit us. (Due to delays in processing and transmission, it'll tell us only after the flare has passed by earth)...
As valadaar states, the light from the flare travels at the speed of light, the actual matter that does the damage travels much more slowly.
Dave
It was my understanding that the main "effects" of flares were that of X-Rays and other forms of radiation (UV, etc) which do travel at the speed of light... http://en.wikipedia.org/wiki/Solar_flare Sure, the massive ejections will travel at less than C, but the effects the OP mentions (radio and GPS interferance) are caused by the X-Rays hitting the ionosphere. And that effect would occur "before" the satellite gets a chance to "warn" us... So while my post was incomplete, it's still applicable... Just not for the entire effect of the flare.
If a man isn't willing to take some risk for his opinions, either his opinions are no good or he's no good
They ARE disrupted by X-Rays, which are part of the spectrum of light... So yes, comms satellites ARE disrupted by LIGHT from the flare. It's the act of these X-Rays hitting the ionosphere that causes the radio interference (hence disrupting the GPS systems that the OP was referring to)...
If a man isn't willing to take some risk for his opinions, either his opinions are no good or he's no good
http://en.wikipedia.org/wiki/Set_the_Controls_for_the_Heart_of_the_Sun
Virtually ALL data from ALL scientific spacecraft is available, right now.
Oh wait, you want to see processed data of interesting things? Yes, that is available too for sun... How about things like,
http://sohowww.nascom.nasa.gov/data/realtime-images.html
Seriously, ALL data is out there and available. Just look for it instead of being just whining on forums about not being fed it trough CNN or Fox or whatever.
Nothing travels faster than the speed of light.
But a lot of things travel slower. One of those things is the solar wind. The real excitement from a large solar flare happens when the stream of charged particles hits Earth's magnetic field and atmosphere. Generally, you get a couple of days of warning. I assume that enormous flares would be faster, but even then you'll probably get hours of warning.