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."

Comments

First we bomb the moon...

[PumpkinDog]

...now we're sending a spaceship to the sun?? I hope they're at least sending it at night so it won't get burnt.

Re:First we bomb the moon...

[Adriax]

Almost 24 hours a day? You mean this thing gets a break every day?
Damn robot rights lobby! Next thing you know it'll be asking for weekends and holidays off!

Re:First we bomb the moon...

[repka]

What's wrong about the sentence? It was pretty much copied from TFA... The orbit is almost geostationary, considering the distance, so it's not like it'll be doing 8's around Earth and Moon, like Apollo crafts.

Rendezvous ?

[mbone]

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.

Re: Rendezvous ?

[zippthorne]

It will be equipped with its own artificial eclipse which will be precisely sized to look at various parts of the photosphere, corona, etc. There is not any real benefit of a lunar eclipse, since the unlit side of the moon would be.. unlit, thus making it equivalent to a small metal disk anyway. I suppose you could talk about lunar mountain ranges, but frankly, the point of an orbital sun-observing satellite is that there isn't any atmosphere to drown out your signal with diffuse light. That is particularly important *before* the occulting disk: the atmosphere can't scatter light that never reaches the atmosphere.

Good observations can be made if the occulting disk is *ahead* of the atmosphere, the problem being the moon is the only appropriately sized disk for an earthbound observatory to use, and it's on the moon's time. If the moon is what you want to observe, you should be able to get pictures of it from earth as well or better than pictures from an equally distant space-based station.

Re: Rendezvous ?

[tweak13]

It is in a geosynchronous orbit, not a geostationary orbit. Any orbit with inclination cannot be geostationary and would require multiple ground stations or a steerable antenna. It may also be possible that they are using a fixed antenna and a highly elliptical orbit, and using that to create a long period of relatively little apparent motion from earth during which to perform their downlinks. That may also be how they create longer observation times.

Either way, this wouldn't allow continuous observation of the sun. It may be close, but at some point it is going to be near enough to the night side of earth to be in its shadow.

Re:Prodigious rush

[DMUTPeregrine]

It's in orbit of earth. It's not going anywhere near the sun, at least not much nearer than earth.

Re:Prodigious rush

[Infiniti2000]

I don't know about the rest of you, but a little piece of me died inside when I read the comparison to iTunes: "It's like downloading 500,000 iTunes a day, NASA stated." Are comparisons to iTunes downloads really needed in today's world?

Re:GPS disuption warning- a good thing

[oneiros27]

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.

Re:GPS disuption warning- a good thing

[mbone]

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.

Re:GPS disuption warning- a good thing

[BubbaDave]

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

Some Advice For the Robot

[Kozar_The_Malignant]

Do not look at sun with remaining camera.

Re:GPS disuption warning- a good thing

[ircmaxell]

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.

Re:GPS disuption warning- a good thing

[ircmaxell]

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)...

Re:Set the controls for the heart of the sun

[Anonymous Coward]

http://en.wikipedia.org/wiki/Set_the_Controls_for_the_Heart_of_the_Sun

Re:GPS disuption warning- a good thing

[BubbaDave]

GPS interference is temporary, I worry more about the ejection products that can cause permanent damage.

Dave

Re:Prodigious rush

[Critical Facilities]

Or did they mean 500,000 average-length songs? When did 'an iTune' mean anything?

Indeed. They should have used specific examples like:

Here Comes the Sun
Black Hole Sun
Good Day Sunshine
House of the Risin' Sun
Walking on the Sun
Blister in the Sun
You Are the Sunshine of My Life
Sunshower
Don't Let the Sun Go Down On Me
Sunless Saturday
California Sun
Walking on Sunshine


You know, something like that.

Re:Prodigious rush

[rockNme2349]

Thats 0.14 Library of Congresses / Day.

Sorry for the confusion.

-NASA

Re:GPS disuption warning- a good thing

[khallow]

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.