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ToSeek
2005-Nov-11, 07:45 PM
Twin APL-Built Solar Probes Shipped To NASA Goddard For Pre-Launch Tests (http://www.spacedaily.com/news/solarscience-05zg.html)


The first spacecraft designed to capture 3-D "stereo" views of the sun and solar wind were shipped Wednesday from the Johns Hopkins University Applied Physics Laboratory to NASA Goddard Space Flight Center for their next round of pre-launch tests.

For most of my time at APL, I was the lead simulations software engineer for the STEREO mission. It got rather frustrating because the launch got ever further away the longer I was there. Nice to see that it's finally about it happen.

ToSeek
2005-Dec-09, 06:50 PM
STEREO spacecraft to image solar blasts in glorious 3-D (http://www.newscientist.com/article.ns?id=dn8438&feedId=online-news_rss20)


Blasts of energetic particles from the Sun will soon be visible barrelling towards Earth in glorious 3-D, thanks to a pair of NASA spacecraft called STEREO. The mission should help researchers to predict which solar storms could endanger astronauts or damage satellites.

Both STEREO (Solar Terrestrial Relations Observatory) spacecraft are scheduled to launch aboard the same Delta 2 rocket from Florida's Cape Canaveral Air Force Station on 26 May 2006.

ToSeek
2006-May-04, 04:34 PM
NASA STEREO Arrives in Florida to Begin Launch Preparations (http://www.spaceref.com/news/viewpr.rss.html?pid=19765)


NASA's Solar Terrestrial Relations Observatory (STEREO) spacecraft arrived today at Astrotech, a payload processing facility near Kennedy Space Center in Florida, to begin preparations and final testing for launch. Liftoff will occur aboard a Boeing Delta II rocket from Launch Complex 17 on Cape Canaveral Air Force Station in the summer.

They just had the "ready-to-ship" review in the auditorium in my office building. I ran into my former task leader and a couple other people I'd worked with.

mugaliens
2006-May-07, 07:12 PM
Nice! When do they launch the SAS missions? (multi-axis "3D" aka dubbed "4D"?)

Hint - it's what was used to build the information for Google Earth's expose of the Grand Canyon. Go close, like 7,000', fly over, and regardless of what direction you move, the canyon tops move faster than the bottom.

That's not just stereo - it's 3D.

Launch window
2006-May-12, 12:32 AM
great to hear this one is going ahead, there's been so much bad news with the last budget cuts

Blob
2006-Jul-17, 11:05 AM
The Launch windows are currently scheduled for 19:.42-19:44 or 20:50-21:05 BST on 1st August, 2006 from the SLC-17B, Cape Canaveral Air Force Station, Florida, US.
The Launch date may slip due to bad weather or other factors.

Read more (http://www.nasa.gov/mission_pages/stereo/main/index.html)

ToSeek
2006-Jul-17, 01:28 PM
(Threads merged).

About time! I started at APL in August of 2000. I think we were about three years from launch according to the schedule at the time. It just kept slipping....

ToSeek
2006-Jul-18, 03:45 PM
Our Sun's fiery outbursts - seen in 3D STEREO Prepares for Launch! (http://www.spaceref.com/news/viewpr.rss.html?pid=20373)


UK solar scientists are eagerly awaiting the launch of NASA's STEREO mission which will provide the first ever 3D views of the Sun. STEREO (Solar TErrestrial RElations Observatory) comprises two nearly identical observatories that will orbit the Sun to monitor its violent outbursts - Coronal Mass Ejections (CMEs) - and the 'space weather' it creates that can impact the Earth, satellites and astronauts. STEREO is due for launch on August 1st 2006.

Professor Richard Harrison of the CCLRC Rutherford Appleton Laboratory (RAL), part of the UK team working on STEREO said "Whilst our Sun may seem a calm familiar object in the sky, in reality it is rather more manic! It generates constantly changing knots of magnetic fields that twist and churn and, occasionally, snap like an over-stretched rubber band producing CME outbursts. At the moment, we cannot recognise the tell-tale signals that precede an outburst, but we expect STEREO will change that."

ToSeek
2006-Jul-18, 05:12 PM
Stereo satellites will let scientists tune in to the sun's mood music (http://www.guardian.co.uk/space/article/0,,1823068,00.html)


Scientists want to create the first three-dimensional model of the sun in an effort to protect the Earth from its most violent eruptions, which can affect everything from global positioning systems to mobile phone networks. The Stereo mission, due to be launched next month, will map the sun's mood swings and the dangers they pose to the solar system.

The $500m (£275m) space mission is funded by Nasa and the European Space Agency. It will consist of a pair of satellites - each more than half a tonne in mass and the size of a large deep freezer - which will monitor activity on the sun's surface for the first time.

mugaliens
2006-Jul-18, 07:07 PM
Twin APL-Built Solar Probes Shipped To NASA Goddard For Pre-Launch Tests (http://www.spacedaily.com/news/solarscience-05zg.html)

For most of my time at APL, I was the lead simulations software engineer for the STEREO mission. It got rather frustrating because the launch got ever further away the longer I was there. Nice to see that it's finally about it happen.

Wow! Would I like to pick your brain! Although I'm more into the hardware end of computing, I'm really intrigued by how people put the software together for these missions. Do you program in assembler?

ToSeek
2006-Jul-18, 08:41 PM
Wow! Would I like to pick your brain! Although I'm more into the hardware end of computing, I'm really intrigued by how people put the software together for these missions. Do you program in assembler?

I used to but haven't for a long time now. The testbed software at APL was written in C++ (as is most of the simulation stuff I'm writing now, except for the user interface, which is in Java). But, so far as I can tell, most flight software (the software onboard the spacecraft) is written in C these days. I can't remember if they were using VxWorks as the operating system, but that's a very common one to use on spacecraft.

SAMU
2006-Jul-20, 03:50 AM
What stereo base is it using? And what is the expected range the viewer is expected to be from the resultant images? I calculate that, for a viewing range that would be comfortably viewed on a computer 36 inches away from the viewer, the stereo base should be 6,250,000 miles. That is the spacecraft should be 6,250,000 miles apart.

ToSeek
2006-Jul-20, 04:14 AM
The separation is not constant. One spacecraft ("Ahead") is put in an orbit in front of the Earth, while the other ("Behind") is put in an orbit trailing the Earth. They each separate from the Earth at a rate of 22 degrees per year relative to the Sun. The nominal two-year mission starts about three months after they go into solar orbit, so the initial separation is about ten degrees, and the final separation is about a hundred degrees (though odds are the mission will continue beyond that point).

It's left as an exercise for the reader to work the actual distances out. ;)

SAMU
2006-Jul-21, 04:24 AM
ToSeek,

You might want to drop your friends a line that the 10 degree seperation results in a stereo base of about 15 million miles. A person viewing the resulting images from a distance of 36 inches will get a hyperstereo appearance. That is the sphere of the sun will look like a football pointed at you not a sphere. To see it as a sphere you will need to be about 17 inches from the image. It is not comfortable to focus on something, let alone a forced parallax image (which is what stereography is), from a distance of 17 inches. And as the spacecraft get farther apart the hyperstereo will get worse. The angle best suited for stereographing the sun so that the images can be comfortably viewed from 36 inches is about 5 degrees or, as I wrote in my first post, about 6.25 million miles.

I am something of an expert in stereography.

ToSeek
2006-Jul-21, 04:51 AM
I assume they will be processing the data to get the "stereo" results rather than just trying to eyeball the images. I do recall that there was some talk about where the optimum position for imagery was, but I don't remember where it was. (Actually, I think it might have depended on which aspect of the Sun was being observed, so the gradually spreading angle was a compromise among all the scientists as well as being easier to do engineering-wise than getting them out a certain distance and stopping.)

SAMU
2006-Jul-22, 08:10 AM
ToSeek,

OOOHHH. I thought it was going to take stereo pictures. I didn't know it was going to take "stereo" pictures. My bad.

ToSeek
2006-Jul-22, 07:47 PM
Yes, the real goal is to be able to do triangulation more than to produce stereo images.

Blob
2006-Jul-23, 09:12 PM
Hum,
yeah nice pictures would be a bonus,
but as toseek implied the real reason for the `stereo` ability is to be able to track large coronal mass ejections heading straight for the Earth. Currently, it is easy to see and track them as they head outwards to the side, but it is more difficult to see the ones that are heading this way and may affect us.

ToSeek
2006-Jul-24, 03:19 AM
More solar physics, please (http://www.thespacereview.com/article/666/1)


The upcoming launch of NASA’s STEREO (Solar Terrestrial Releations Observatory) probes is a sign that NASA’s science directorate has not lost sight of the original goals of the “Living With a Star” program. They will be launched on a single Delta 2 no earlier than August 20th and will provide the solar physics community with an unprecedented three-dimensional view of our Sun’s coronal mass ejections, (CMEs). These are the single most spectacular and significant “local” space weather events.

ToSeek
2006-Jul-31, 03:52 PM
Solar spacecraft launch delayed (http://www.floridatoday.com/floridatoday/blogs/spaceteam/2006/07/solar-spacecraft-launch-delayed.html)


NASA has delayed the launch of a solar research mission until no earlier than Aug. 31 to allow inspectors to check out a suspect tank on its Delta 2 rocket.

An oxidizer tank on a similar Delta 2 rocket at an Alabama factory has prompted the need for all such tanks to be checked out before launch.

The second stage can't be checked out while still on top of the first stage at Launch Complex 17 at Cape Canaveral Air Force Station. The rocket therefore will be taken apart and taking a nearby test facility for leak checks. The de-stacking work begins Tuesday and will take about a week.

SAMU
2006-Aug-06, 06:38 AM
I bet you that I am enough of a stereograph expert that I would be able to tell you how far a coronal mass ejection is from the sun within a million miles (1 percent) by eye with a properly set up stereograph, and I could tell you how fast it is going and whether it is coming directly towards us with two pictures taken when the mass has moved 2 million miles between pictures before it is 5 million miles from the sun and knowing the time between pictures. I could probably also give you estimates of the LWH sizes of any structures within the mass to an accuracy of one percent of the resolution of the images.

Launch window
2006-Aug-06, 03:30 PM
I bet you that I am enough of a stereograph expert that I would be able to tell you how far a coronal mass ejection is from the sun within a million miles (1 percent) by eye with a properly set up stereograph, and I could tell you how fast it is going and whether it is coming directly towards us with two pictures taken when the mass has moved 2 million miles between pictures before it is 5 million miles from the sun and knowing the time between pictures. I could probably also give you estimates of the LWH sizes of any structures within the mass to an accuracy of one percent of the resolution of the images.

It should be a fantastic mission

Blob
2006-Aug-14, 06:08 PM
NASA is hosting a media teleconference about the Solar TErrestrial RElations Observatory (STEREO) mission on Thursday, August 17 at 2 p.m. EDT.

Briefing participants:
-- Madhulika Guhathakurta, STEREO program scientist, NASA headquarters, Washington
-- Michael Kaiser, STEREO project scientist, Goddard Space Flight Center, Greenbelt, Md.
-- Ed Reynolds, STEREO project manager, Johns Hopkins University Applied Physics Laboratory, Laurel, Md.
-- Nicholas Chrissotimos, STEREO project manager, Goddard

The nearly identical twin observatories will provide 3-D views of the sun and solar wind, perspectives critical to improving understanding of space weather, its impact on astronauts and Earth systems. The satellites will launch aboard a Delta II rocket from Kennedy Space Centre, Florida, US, on Thursday, August 31, for a two-year mission.

Source (http://www.nasa.gov/home/hqnews/2006/aug/HQ_M06127STERO_media_update.html)

ToSeek
2006-Aug-16, 06:18 PM
Solar observatories get new launch date (http://www.theregister.co.uk/2006/08/16/stereo_mission/)


NASA and PPARC have confirmed that the STEREO mission (the acronym cunningly derived from Solar TErrestrial RElations Observatory) is slated to launch on 31 August.

Blob
2006-Aug-16, 06:35 PM
Hum,
i have a date for August 31st; there is a 2 minute launch window that starts at 19:12 GMT, and a 15 minute launch window that starts at 20:20 GMT.

ToSeek
2006-Aug-16, 07:39 PM
I used to work with a guy whose nearly-full-time job it was to figure out the launch windows and solar orbit insertion profiles for every possible STEREO launch date. Considering all the delays, he's probably been pretty busy.

ToSeek
2006-Aug-18, 10:17 PM
NASA press release:

NASA Satellites Will Improve Understanding of the Sun (http://www.nasa.gov/home/hqnews/2006/aug/HQ_06294_STEREO_press_packet.html)


NASA's Solar Terrestrial Relations Observatory mission will dramatically improve understanding of the powerful solar eruptions that can send more than a billion tons of the sun's outer atmosphere hurtling into space.

The STEREO mission comprises two nearly identical spacecraft the size of golf carts, which are scheduled to launch on Aug. 31 aboard a Delta II rocket from Cape Canaveral Air Force Station, Fla. Their observations will enable scientists to construct the first-ever three-dimensional views of the sun. These images will show the sun's stormy environment and its effect on the inner solar system. The data are vital for understanding how the sun creates space weather.

During the two-year mission, the two spacecraft will explore the origin, evolution and interplanetary consequences of coronal mass ejections, some of the most violent explosions in our solar system. When directed at Earth, these billion-ton eruptions can produce spectacular aurora and disrupt satellites, radio communications and power systems. Energetic particles associated with these solar eruptions permeate the entire solar system and may be hazardous to spacecraft and astronauts.

"In terms of space-weather forecasting, we're where weather forecasters were in the 1950s," said Michael Kaiser, STEREO project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "They didn't see hurricanes until the rain clouds were right above them. In our case, we can see storms leaving the sun, but we have to make guesses and use models to figure out if and when they will impact Earth."

To obtain their unique stereo view of the sun, the two observatories must be placed in different orbits, where they are offset from each other and Earth. Spacecraft "A" will be in an orbit moving ahead of Earth, and "B" will lag behind, as the planet orbits the sun.

Just as the slight offset between eyes provides depth perception, this placement will allow the STEREO observatories to obtain 3-D images of the sun. The arrangement also allows the spacecraft to take local particle and magnetic field measurements of the solar wind as it flows by the spacecraft.

STEREO is the first NASA mission to use separate lunar swingbys to place two observatories into vastly different orbits around the sun. The observatories will fly in an orbit from a point close to Earth to one that extends just beyond the moon.

Approximately two months after launch, mission operations personnel at the Johns Hopkins University Applied Physics Laboratory, Laurel, Md., will use a close flyby of the moon to modify the orbits. The moon's gravity will be used to direct one observatory to its position trailing Earth. Approximately one month later, the second observatory will be redirected after another lunar swingby to its position ahead of Earth. These maneuvers will enable the spacecraft to take permanent orbits around the sun.

Each STEREO observatory has 16 instruments. The observatories have imaging telescopes and equipment to measure solar wind particles and to perform radio astronomy.

"STEREO is charting new territory for science research and the building of spacecraft. The simultaneous assembly, integration and launch of nearly identical observatories have been an extraordinary challenge," said Nick Chrissotimos, STEREO project manager at Goddard.

The STEREO mission is managed by Goddard. The Applied Physics Laboratory designed and built the spacecraft. The laboratory will maintain command and control of the observatories throughout the mission, while NASA tracks and receives the data, determines the orbit of the satellites, and coordinates the science results.

For more information about STEREO, visit:

http://www.nasa.gov/stereo


For more information about NASA and agency programs, visit:

http://www.nasa.gov/home

Wolverine
2006-Aug-19, 12:27 AM
Looking forward to the launch. :D

Blob
2006-Aug-21, 09:30 PM
Two nearly identical spacecraft, destined to capture the first-ever 3-D views of the sun, are scheduled for launch on Aug. 31 aboard a Delta II rocket from Cape Canaveral Air Force Station, Fla., at 3:12 p.m. or 4:20 p.m. EDT. The window extends through Sept. 4 with two launch opportunities daily.

Read more (http://www.jhuapl.edu/newscenter/pressreleases/2006/060817.asp)

ToSeek
2006-Aug-22, 02:51 PM
STEREO launch delayed (http://www.floridatoday.com/apps/pbcs.dll/article?AID=/20060821/BREAKINGNEWS/308210004/1086)


The launch of twin solar research spacecraft has been delayed to mid-September to allow more time to check out the Delta 2 rocket's second stage to make sure it is safe for flight. NASA on Monday announced the launch will move back to no earlier than Sept. 18.

Wolverine
2006-Aug-23, 06:38 AM
Doh. That second stage is being a pain.

Launch window
2006-Aug-24, 12:38 AM
STEREO launch delayed (http://www.floridatoday.com/apps/pbcs.dll/article?AID=/20060821/BREAKINGNEWS/308210004/1086)

better safe than sorry, hope this goes well - it shoudl be a great mission

ToSeek
2006-Aug-30, 02:49 PM
Better Predictions of Space Weather

NASA spacecraft monitoring solar storms will help prevent damage to satellites. (http://www.technologyreview.com/read_article.aspx?id=17378&ch=infotech)


Next month NASA will launch a pair of spacecraft that will help astronomers study and predict gigantic eruptions from the sun. Currently, the nature and causes of these explosions of high-energy particles and magnetic storms are poorly understood. And being able to predict them farther in advance will help prevent damage to satellites orbiting the Earth.

In the past, astronomers have been able to look at these solar storms, called coronal mass ejections (CMEs), only from the Earth. This limited perspective has made predicting the exact timing and extent of the solar storms difficult, says Janet Luhmann, a researcher at the University of California at Berkeley's Space Science Laboratory, who helped design instruments for the new spacecraft. She compares it to "being run over by a truck: we don't see the full velocity and size of what's coming at us." The two new NASA spacecraft, called STEREO, will orbit the sun in front of and behind the Earth, giving a far better view of the solar storms.

The myriad project delays might end up being a good thing: STEREO has a good chance of observing the next solar maximum. If it had launched a couple of years ago, as originally scheduled, it would now be observing a relatively quiet Sun.

SAMU
2006-Aug-31, 09:13 AM
Here is a work around for the stereo base problem.

Since the two space craft are going to be 10 degrees apart then they should each average about 5 degrees from Earth. If a satelite at Earth takes the same picture at the same time then we would have a reasonably close stereo base for viewing on a monitor at 36 inches.

Personally, I'm looking forward to viewing the pictures even if they are distorted visually.

ToSeek
2006-Aug-31, 01:52 PM
The separation between the two spacecraft isn't fixed but gradually increases over time:

http://stereo.jhuapl.edu/mission/overview/images/chart_lg.gif

SAMU
2006-Sep-01, 11:53 AM
To Seek,

I'm not sure if your message was addressed to me. I did understand that the spacecraft would be getting farther apart as time goes by. So the window of opportunity will be short for getting visually correct stereographs.

I also understand that to start taking pictures at 5 degrees to get the optimum seperation for visual stereographs means that the spacecraft would have to start taking the pictures sooner, and while that that may sound simple enough, I understand that it could conflict with other flight goals or programming.

That is why I posted the work around of also taking pictures from an Earth orbit camera coordinated to the stereo mission cameras. While that would not yield ideal stereographs unless the camera at Earth matched the ones on the stereo mission it would enlarge the window of opportunity for getting visually correct stereographs without changing the stereo mission in any way.

I've seen some of the stereo pictures on the NASA site and it's obvious to me that NASA needs some help in the stereographic department. Most of the errors are as simple as they are devastating to the stereographic effect for example; some of NASA's images have one eye's image much larger than the other eye's image. I have seen images rotated differently, vertical axis offset, differing brightness, differing contrast, differing focus and incorrect stereo base. All these things make the stereographs NASA produces either flat, hyperstereo, difficult or impossible to bring into stereo focus or heavily artifacted which makes the stereo image look like it's floating in cloudy or dirty water.

If you still have contacts with NASA you are welcome to put them in touch with me. I would be happy to help them get better stereographs.

ToSeek
2006-Sep-01, 02:34 PM
I'm just a NASA peon, but in the unlikely chance that I run into someone appropriate, I'll let them know.

I'm not sure what the commissioning period is for STEREO. My guess is that they'll probably just be coming out of it and going operational at the 5-degree point.

ToSeek
2006-Sep-01, 09:56 PM
STEREO launch even more delayed (http://www.floridatoday.com/floridatoday/blogs/spaceteam/2006/09/stereo-launch-delayed.html)


The launch of the mission is now set for no earlier than Oct. 18 from Pad 17B at Cape Canaveral Air Force Station. The two STEREO spacecraft remain in a processing facility near the Cape.

SAMU
2006-Sep-02, 05:08 AM
Actually, if the spacecraft cameras are coordinated with a camera at Earth it would provide three windows of opportunity for correct stereographs. The first is when the spacecraft are 5 degrees from each other. The second is when the spacecraft that is farthest from Earth reaches five degrees from Earth and the third and last is when the spacecraft that is closest to earth reaches five degrees from Earth. After that the images will be getting contiuously more and more hyperstereographicaly distorted as they get farther apart.

I don't know if they will still be opperational but presumably there could be another 2 windows of opportunity when they continue around the sun relative to each other and approach each other again in several years.

ToSeek
2006-Sep-03, 01:57 AM
I would think that some of the instruments would be compatible with SOHO, which isn't at the Earth but a million miles in front, so it's at the same angle.

SAMU
2006-Sep-07, 11:20 AM
The stereo base I posted earlier of approximately 6,250,000 (exactly 6,388,888) miles would make images for viewing on a monitor from a distance of 36 inches. However, if the spacecraft started taking pictures sooner, when they are 4,791,666 miles apart then the pictures would be properly set up for viewing at a distance of 40 feet like in an IMAX theater. Can you imagine? the sun in 3-D in IMAX?

By the way the formula for calculating what the stereo base (the distance between cameras for 3-D pictures) should be so the pictures would be properly proportional in highth width and depth is to divide the distance between the eyes (usually 2.5 inches) by the distance in inches to the image being viewed. You then multiply the result by the distance to the object being photographed. The result of that will give you how far apart the cameras should be for any givin distance you plan to view the resulting images from.

Launch window
2006-Sep-14, 08:06 PM
I would think that some of the instruments would be compatible with SOHO, which isn't at the Earth but a million miles in front, so it's at the same angle.


I think Soho has been one of the best unmanned missions done by NASA

Kullat Nunu
2006-Sep-14, 08:36 PM
Actually SOHO is an ESA/NASA joint mission. ESA build the spacecraft and most of the instruments are built in ESA member countries. Of the principal investigators nine are from ESA countries and three are from the USA. NASA launched the mission and is responsible for the mission operations.

ToSeek
2006-Sep-14, 09:43 PM
SOHO is pretty cool. It's the only spacecraft I know of that has effectively gone from research status to operational status. But it's getting really, really old, and it will be nice to have STEREO up there as a backup, not even considering all the other nifty things STEREO will be able to do.

ToSeek
2006-Oct-18, 05:05 PM
Great balls of fire (http://www1.umn.edu/umnnews/Feature_Stories/Great_balls_of_fire.html)


In outer space as on Earth, real estate is all location, location, location. That's particularly true for the twin spacecraft of NASA's STEREO mission, which will be positioned far apart in space to give the first binocular, or 3-D, view of the sun. Set for launch tomorrow (Oct. 25, 2006), STEREO aims to learn more about the causes of spectacular eruptions of hot, magnetic bubbles of gas thrown off by the sun and how to identify those that are headed toward Earth, where they can disrupt power grids and communications. On board are University-designed and built instruments to search for clues to how these explosions-the most powerful in the solar system-happen.

Blob
2006-Oct-18, 05:19 PM
Cool,
tomorrows news today.

NASA's Solar Terrestrial Relations Observatory mission will launch from SLC-17B, Cape Canaveral Air Force Station, between 00:38-00:53 GMT on the 26th October.

ToSeek
2006-Oct-24, 06:18 PM
Sun-gazing spacecraft primed for launch at last (http://www.newscientistspace.com/article.ns?id=dn10370&feedId=online-news_rss20)


NASA's pair of Sun-gazing spacecraft is finally set to launch tomorrow evening after months of delays. The duo, aptly named STEREO, will observe solar flares in glorious 3D.

The mission should help researchers predict which solar storms could endanger astronauts or damage satellites.

The two STEREO (Solar Terrestrial Relations Observatory) spacecraft are scheduled to launch aboard the same Delta 2 rocket from Cape Canaveral in Florida, US, sometime after 2038 EDT on Wednesday (0038 GMT on Thursday).

Once in space, they will split up to observe the Sun from different angles, between them capturing images in 3D. The idea mimics the way people naturally gauge depth, using the slightly different perspective from each eye.

01101001
2006-Oct-26, 12:15 AM
Launch Date: Oct. 25, 2006
Launch Window: 8:38 - 8:53 p.m. EDT

Launch coverage:

STEREO Launch Blog (http://www.nasa.gov/mission_pages/stereo/launch/vlcc.html) current:


8:05 p.m. [Easter Daylight Time zone] - NASA Launch Manager Omar Baez is polling the launch team to verify they're ready to proceed with the countdown, and the team is ready.

7:53 p.m. - The countdown clock is holding at T-15 minutes. This is a 20 minute built-in hold.

7:50 p.m. - Weather officer Joel Tumbiolo just gave another promising weather briefing. The radar continues to show no precipitation, winds are less than 10 knots, and there's really no change to the earlier forecasts. There is virtually no chance that weather will interfere with tonight's launch plans. The launch team is "green" on all weather constraints.

Watch NASA TV (http://www.nasa.gov/multimedia/nasatv/index.html)

01101001
2006-Oct-26, 12:18 AM
Hold off

T - 15 minutes and counting
(There's a 10-minute built-in hold at T - 4 minutes)

01101001
2006-Oct-26, 12:29 AM
2024 EDT

Built-in 10-minute hold at T - 4 minutes.

14 minutes to open launch window at 2038 EDT.

01101001
2006-Oct-26, 12:40 AM
Two issues


8:26 p.m. - T-4 minutes and holding for 10 minutes. Evaluation of the toxics issue continues, but weather is "go" otherwise. There is an issue with gaseous nitrogen bottles. The bottles are out of limits and too cold. The launch team will try to warm the bottles up, which could take us past the opening of the window.

2034 EDT

T - 4 minutes and still holding

Target is end of launch window, I think they said 2050 EDT.

2036 EDT

Nitrogen bottle issue solved. They're warm.

Range is still red. (Earlier in blog: Range safety is red at this time due to the possibility that toxics from the vehicle could disperse over local populated areas, should there be a mishap. Additional weather balloons are being launched to monitor this.)

Target is 2052 EDT.

01101001
2006-Oct-26, 12:47 AM
Preliminary word: range green.

Will pick up countdown at 2048 EDT at T - 4 minutes

2043 EDT

Officially: Range green; Ready to proceed; Target 2052 EDT

Grand_Lunar
2006-Oct-26, 12:53 AM
Still green.

Proceeding with terminal countdown.

Hold released, four minutes and counting.

Vechile is armed.

Grand_Lunar
2006-Oct-26, 12:55 AM
Two minutes, twenty seconds.

Grand_Lunar
2006-Oct-26, 12:56 AM
90 seconds.

Grand_Lunar
2006-Oct-26, 12:56 AM
60 seconds.

Grand_Lunar
2006-Oct-26, 12:57 AM
30 seconds, going outside to see this now.

01101001
2006-Oct-26, 12:57 AM
Liftoff

Go, go, you two!

Max q still good

solid burnout

6 miles

jettison

3 good air-start motors

3000 mph

T + 150 seconds

all nominal

27 miles up

jettison

36 miles up downrange 100 miles 6000 mph

T + 250

MECO; first stage jettison; second stage ignition

Grand_Lunar
2006-Oct-26, 01:02 AM
Saw the flight from my place in Fort Lauderdale. Awesome!

01101001
2006-Oct-26, 01:08 AM
second stage nominal

15750 MPH

T + 575

16500 MPH



nominal SECO

Orbit!

dinner time...

Grand_Lunar
2006-Oct-26, 01:26 AM
All right, in orbit!

Another mission for the books.

Blob
2006-Oct-26, 01:32 AM
T+plus 25 minutes.
Release of the STEREO spacecraft from the Delta rocket.

sandy_freelance
2007-Jan-03, 05:37 PM
Hi,



> the stereographs NASA produces either flat, hyperstereo, difficult or impossible to bring into stereo focus or heavily artifacted which makes the stereo image look like it's floating in cloudy or dirty water.

If you still have contacts with NASA you are welcome to put them in touch with me. I would be happy to help them get better stereographs.

One issue is that when we look at, say, CMEs from the sun, or flares, we're not looking at solids. The material itself is optically thin (akin to smoke rather than particles). So, for example, your earlier example of 'using a stereograph, you could estimate an Earth-bound CME' would not work (unfortunately). One reason STEREO is the first mission able to see Earth-bound CMEs is that you need the side view in order to figure out the vectors for optically thin stuff.

Another hassle with optically thin material is most 3D visualization or reconstruction work is based on solids. The closest field similar to us is clouds, especially for flight sim work, and there they use algorithmic approximations rather than actual optically thin rendering. So our problem is twofold: figure out the underlying distribution of optically thin material based on only 3 (STEREO A&B + LASCO) viewpoints, then figure out how to visualize that optically thin material.

For white light in the corona, the emission is Thompson scattering, so any rendering is dependent not only on the amount of material along the entire line of sight, but also on the scattering angle of each blob of material relative to the sun. It's easily solved but hard to do quickly for high resolution data, so data browsing or rotating a model is usually done in wireframe mode, then you (slowly) render for just a chosen viewpoint.

So to make a stereogram if the actual satellite separation is not exactly matching our visual separation, you have to make a model, then artificially render the view from the appropriate separation. Or, munge it in other ways to mimic the separation. Or, use rotational tomography, where you snap a frame, allow the sun to rotate the appropriate amount, then snap your second frame.

But there are two problems with solar rotational tomography (which is what you see with LASCO stereograms). First, the sun has differential rotation, so different latitudes rotate at different speeds. Second, the features we most want to see are evolving over time, so they will change between shots. So we're looking at evolving, differentially rotating, optically thin features. Tricky stuff.

That said, feel free to email me if you think your stereography knowledge might apply in this realm. As you might guess from the above, while I'm not at NASA I do work on analyzing coronograph data, and STEREO is new to me too!

SAMU
2007-Jan-04, 12:33 PM
Hi,



One issue is that when we look at, say, CMEs from the sun, or flares, we're not looking at solids. The material itself is optically thin (akin to smoke rather than particles). So, for example, your earlier example of 'using a stereograph, you could estimate an Earth-bound CME' would not work (unfortunately). One reason STEREO is the first mission able to see Earth-bound CMEs is that you need the side view in order to figure out the vectors for optically thin stuff.

I beg to differ. If you see (to use your example) a puff of smoke or a smoke ring or fire in front of you, although they are "optically thin", you would easily (and obviously) see them threedimentionally.

The rest of your post seems to be related to realistically mapping images onto wire frame models in computer rendering programs. My post was not related to that but you are saying that that would be an inferior method and I agree.



For white light in the corona, the emission is Thompson scattering,
You might be interested in my image of the "Bravo" nuclear test which illustrates it very well except that in my image it is red light scattered by mist in the air surrounding the fireball.


So to make a stereogram if the actual satellite separation is not exactly matching our visual separation, you have to make a model, then artificially render the view from the appropriate separation.

As I wrote in earlier posts, the appropriate seperation (there isn't an "exact" seperation) of the satelites is dependant on the distance the person viewing the image is from the image. I refer you again to my earlier post where I wrote (in short) that when viewing a stereo image from a distance of 20 to 40 feet in a movie theatre the satelites would need to be closer together when they take the pictures than they would need to be if viewing stereo images from a distance of 20 to 40 inches on your computer monitor where the satelites would need to be farther apart.

sandy_freelance
2007-Jan-10, 08:15 PM
Hi,

> although they are "optically thin", you would easily (and obviously) see them threedimentionally.

No, optically thin means optically thin. I should have skipped the smoke metaphor, it's a bad analogy. Optically thin means you can tell how much material is along the line of sight, but you cannot tell the position of the material. A single blob of plasma at a distance appears the same as an extended but less dense blob along the line of sight.

So you use modeling (not wireframe as you suppose) to figure out, from all the possible underlying distributions which could produce the observed 2D image pair (or trio), what distribution(s) are most likely.

Also, since our seperation is determined by the orbital necessity, not us, we can't tweak the seperation to fit your stereo pair analogy. Hence the need for rendering techniques (figure out the stuff, the render it from a human-stereo seperation).

That said, this is for coronograph white light data. Some EUV type data does use more direct methods (although again, we can't control the seperation). If you are interested, you might want to look it up, it's harder and more physics-y than it first appears.

SAMU
2007-Jan-12, 09:48 AM
I agree that we can't control the seperation but, as I wrote in an earlier post, there are several windows of opportunity during the mission that will allow true stereographs to be taken for different viewing purposes.
I think it would have been nice if this picture
http://www.nasa.gov/mission_pages/stereo/news/first_light.html
had been taken with a stereographic complement taken at the same time.
I hope that the windows of opportunity don't pass without being taken advantage of in some way.

Unfortunately I can't seem to find a mission profile that gives a detailed timeline of when the spacecraft will be in the correct positions for the various windows. The only timeline I can find has "...separating from each other by about 45 degrees per year. Scientists expect the two to be in position to produce 3-D images by April 2007." I suspect that they will, unfortunately, be too far apart to take advantage of the windows of opportunity for true stereographs by then. I suspect that the window of opportunity of 4,791,666 miles apart for the pictures to be properly set up for viewing at a distance of 40 feet like in an IMAX theater has already passed.
Does anyone know the current seperation of the spacecraft (in miles please)? And are they coordinating with Earth orbit cameras for more windows of opportunity? What is the timeline for the ahead and behind spacecraft?

sandy_freelance
2007-Jan-17, 03:17 PM
Hi again,

> I think it would have been nice if this picture [...] had been taken with a stereographic complement taken at the same time.

Me too, but it was first light for the first telescope so spacecraft B wasn't even open yet. They open things one at a time to reduce risk and ensure operational success. In fact, they've just opened the last of the 20 telescopes (10 per satellite) last week (HI on spacecraft B... caught Comet McNaught with it by intent.) They're expecting regular science ops to begin Jan 22.

For an idea of the weird positions and angles of the early mission, while the flight engineers were doing the hard rocket science stuff to get to the precise long-term orbits, visit the SECCHI wiki at secchi.nrl.navy.mil and follow links to wiki, planning, 'plots of early mission Roll and Separation Angle'.

> Unfortunately I can't seem to find a mission profile that gives a detailed timeline of when the spacecraft will be in the correct positions for the various windows.

After a bit of hunting, I found a 'Where is STEREO' page: http://stereo-scc.nascom.nasa.gov/where.shtml I hope that helps!

>The window of opportunity of 4,791,666 miles apart for the pictures to be properly set up for viewing at a distance of 40 feet like in an IMAX theater has already passed.
[...]
> Does anyone know the current seperation of the spacecraft (in miles please)?

What seperation angle is needed for that, assuming each spacecraft at exactly 1AU from the Sun? (Right now they're at 0.322 apart... assuming that's degrees they're just 535,680 miles apart).

> And are they coordinating with Earth orbit cameras for more windows of opportunity?

Yes, the LASCO detectors are, essentially, at Earth and thus in the middle of the 2 STEREO positions, and are similar detectors, and LASCO is coordinating with STEREO. While LASCO lasts, it's the third eye for STEREO.

So it's easy to solve for where things are. Assume a circle of 1AU, sun is in center. Given any seperation angle from Earth 'Theta' where spacecraft A is at +Theta from Earth and spacecraft B is at -Theta from Earth, and LASCO is at '0', you can do a quick triangle to get any relation you want with basic trig (distance between AB, ALasco,BLasco). You can also reverse it with basic trig-- if you want a seperation of 'L', using 22 degrees/year as Theta you can figure out how many days it'll take to get there. 1AU is about 92,955,807 miles. All just points on a 1AU circle. Enjoy!

ToSeek
2007-Jan-17, 08:37 PM
STEREO featured on January 17th APOD. (http://antwrp.gsfc.nasa.gov/apod/ap070117.html)

Launch window
2007-Jan-20, 02:18 AM
This should be a great mission, it also has some wonderful instrument packages

ToSeek
2007-Jan-24, 06:41 PM
Twin Spacecraft Swing Past Moon, Preparing For 3-D Solar Studies (http://www.sciencedaily.com/releases/2007/01/070124085052.htm)


NASA's twin STEREO (Solar TErrestrial RElations Observatory) spacecraft, built and operated by the Johns Hopkins University Applied Physics Laboratory (APL), in Laurel, Md., completed a series of complex maneuvers Sunday to position the spacecraft in their mission orbits. The spacecraft will be in position to produce the first 3-D images of the sun by April.

STEREO-A went into solar orbit (independent of Earth) December 15. STEREO-B got flung into its trailing orbit just a few days ago, on January 21. Position charts and other tools are accessible here. (http://stereo.gsfc.nasa.gov/where.shtml) Looks as if some digging might answer SAMU's questions.

SAMU
2007-Jan-25, 05:15 AM
I need some more help here interpreting the NASA nomenclature. On this page http://stereo.gsfc.nasa.gov/where.shtml is a (crude to say the least) image of the spacecraft's seperation in terms of (on the left image) A.U. (HEE) scale. and on the right (which as you can see in the image is a more detailed, and usable for calculating stereo base, scale) (GSE) scale. Any idea what (GSE) means in terms of miles or A.U.?

At any rate, it appears that the spacecraft have not yet passed their seperation windows of opportunity for correct stereo base for the various viewing formats, ie seperation of 4,791,666 miles for movie theater viewing of 20-40 feet, and seperation of 6,250,000 miles for home computer viewing of 3 feet. However it does appear, according to the crude quicktime movie of the flight profile, that they will be in the area of the correct stereo base for all visual formats from May through July. Photos taken in July and late July will be best for viewing on a home computer from a distance of 40 inches. Prior to that they will appear flat on a home computer and after that they will be hyperstereographicly distorted but in June-July they will really start to pop out of the screen.

01101001
2007-Jan-25, 07:41 AM
Any idea what (GSE) means in terms of miles or A.U.?


NASA Goddard Glossary (http://lep694.gsfc.nasa.gov/lepedu/glossary.html#G)


Geocentric Solar Ecliptic Coordinates (GSE)
A 3-axis (x,y,z) coordinate system (see graphic), with the Earth at its center, and where the x-axis points to the Sun, the z-axis is perpendicular to the ecliptic plane, and the y-axis is perpendicular to both the x and z axes with a positive direction opposite to the Earth's motion around the Sun.

I believe the units on that axis are AU like the other axes and other diagram.

From the diagram (http://stereo.gsfc.nasa.gov/where.shtml):


Units are in A.U.

ToSeek
2007-Jan-25, 07:43 PM
That would be consistent with the Moon's orbit on the diagram, which should be on the order of 0.0026 AU.

ToSeek
2007-Mar-01, 07:45 PM
Twin spacecraft track solar storms, NASA says (http://news.yahoo.com/s/nm/20070301/sc_nm/sun_storms_dc_2)


New twin spacecraft are helping scientists track pesky solar storms from the sun to Earth, where they can disrupt satellites, communications and sometimes the electricity supply, the U.S. space agency said on Thursday.

Even though the STEREO spacecraft are struggling to get into their final orbits, they are already sending back images that have experts re-evaluating what they know about these storms, called coronal mass ejections, project scientists said.

I don't know about the "struggling" bit - so far as I know, they're doing just fine. It just takes some time for them to get into position.

01101001
2007-Mar-03, 11:45 PM
As noted in the BA Blog (STEREO Eclipse (http://www.badastronomy.com/bablog/2007/03/02/stereo-eclipse/)), images, and a movie, of solar eclipse, with a tiny moon (http://stereo.gsfc.nasa.gov/gallery/stereoimages/preview/preview_transit.shtml)

http://stereo.gsfc.nasa.gov/img/stereoimages/preview/transit_series_time.jpg (http://stereo.gsfc.nasa.gov/gallery/stereoimages/preview/preview_transit.shtml)

ToSeek
2007-Mar-04, 03:27 AM
The solar eclipse movie is truly awesome!

ToSeek
2007-Apr-19, 06:44 PM
3-D images coming next week (http://www.upi.com/NewsTrack/Science/2007/04/19/nasa_to_release_3d_images_of_the_sun/)


NASA scientists said 3-D images of the sun taken by the Solar Terrestrial Relations Observatory are expanding our understanding of solar physics.

The images, to be released Monday on the Internet, television and at museums, are also expected to help improve space weather forecasting.

sarongsong
2007-Apr-21, 03:47 AM
aqui
The pair of...spacecraft...have imaged (http://www.nasa.gov/images/content/170280main_STEREO.long_stand.HD720p.0002.tif)two massive streams of hot plasma streaking away from the sun (blue) at more than 1000 kilometers per second... ScienceNow (http://sciencenow.sciencemag.org/science-shots/)

ToSeek
2007-Apr-23, 04:05 PM
And here (http://www.nasa.gov/mission_pages/stereo/news/stereo3D_press.html) they are.

http://www.nasa.gov/images/content/174621main4_Image1ASm.jpg

Dubb
2007-Apr-23, 05:30 PM
-

Launch window
2007-Apr-25, 01:05 PM
great images

this is going to be a wonderful mission

Jerry
2007-Apr-26, 05:08 PM
I tried to extract the 2 images from eachother so that they can be viewed like a stereogram.

Is the depth perception in these images real or intentially exaggerated?

Dubb
2007-Apr-27, 03:05 AM
-

ToSeek
2007-May-09, 06:19 PM
On Guard: NASA Plans Trio of Sun-Watching Missions (http://www.space.com/businesstechnology/070509_tw_soho_rocks.html)


With some researchers predicting the onset of severe solar weather in a few years, NASA is planning to triple team the Sun by keeping one ancient craft alive to provide critical support for two fancy new missions.

The SOHO spacecraft has been the workhorse of space weather forecasting since it began observing the Sun in 1995. It has weathered storms of its own, suffering electrical problems and various malfunctions that rendered it all but dead on more than one occasion.

But SOHO (Solar and Heliospheric Observatory) has endured, longer than any other solar-dedicated observatory. Designed as a two-year mission, funding to operate the craft has been extended twice in the past so it could cover a complete 11-year solar cycle.

And now, even though it is being upstaged by the more glamorous 3-D Solar TErrestrial RElations Observatory (STEREO) images, SOHO has received funding through 2009. Why? Turns out, there are crucial observations only SOHO can do in the effort to monitor the raging Sun. Even next year, when the Solar Dynamics Observatory (SDO) is slated to launch, SOHO will remain a vital part of the three-mission observation team.

"SOHO has been a godsend in terms of advancing our science in the years it's been up," said Joseph Kunches, lead forecaster at the NOAA Space Environment Center. "SOHO has already taken us and lifted the whole profession up to the first floor of the building from the basement, and now we're trying to go higher."
...
"Right now, we have somebody standing at home plate and the Sun is the pitcher and it's throwing us these fast balls," Kunches said in a phone interview. STEREO will provide "first-base and third-base coaches," watching what's coming from the "pitcher" to the "batter," he said. "They'll be able to tell us better than ever when [a pitch or a solar storm] is going to arrive at home plate, at the Earth."

ToSeek
2008-Jul-02, 06:05 PM
First images of solar system's invisible frontier (http://www.physorg.com/news134223453.html)


NASA's sun-focused STEREO spacecraft unexpectedly detected particles from the edge of the solar system last year, allowing University of California, Berkeley, scientists to map for the first time the energized particles in the region where the hot solar wind slams into the cold interstellar medium.

ToSeek
2009-Feb-20, 06:25 PM
STEREO: Into the Lagrangian Points (http://www.centauri-dreams.org/?p=6228)


Now I see that the two STEREO spacecraft may be pressed into service to study what’s lurking in the L4 and L5 Lagrangian points, each 150 million kilometers from Earth, with L4 60 degrees in front of our planet and L5 60 degrees behind. Balancing the gravitational field of the Sun with that of Earth, the Lagrange points are interesting places, possibly a junkyard of debris from the early Solar System. It’s known that such points appear around other planets, as witness the thousand or so asteroids that make up the Trojans at Jupiter’s L4 and L5 points.

sandy_freelance
2009-Feb-21, 02:46 PM
Hi again! Yep, I wrote a semi-humorous take on this on Scientific Blogging (http://scientificblogging.com/sky_day/), along with a mis-identification of STEREO in a picture. The STEREO HI imagers are just fantastic wide-field sensors for all sorts of repurposing.


STEREO: Into the Lagrangian Points (http://www.centauri-dreams.org/?p=6228)

slang
2009-Feb-22, 10:20 AM
Hi again! Yep, I wrote a semi-humorous take on this on Scientific Blogging (http://scientificblogging.com/sky_day/), along with a mis-identification of STEREO in a picture. The STEREO HI imagers are just fantastic wide-field sensors for all sorts of repurposing.

Yeah, the satellites are in a perfect position to provide 3d targetting data for that Cosmos ;) If it amuses you, there is a conspiracy thread (http://www.bautforum.com/conspiracy-theories/84930-iridium-33-cosmos-2251-collision-not-accident.html)on that collision.

Great article on the Lagrange point study. Can't wait to see results from that!

hhEb09'1
2009-Feb-22, 04:00 PM
Obligatory pun: Voyage to the Dark Side of the Sun (http://www.bautforum.com/space-exploration/84861-dark-side-sun.html) :)

ToSeek
2014-Jun-27, 07:50 PM
Problems you run into when a mission goes beyond its planned lifetime:

Solar conjunction to cause problems for STEREO probes (http://stereo-ssc.nascom.nasa.gov/solar_conjunction.shtml)


Unexpectedly high temperatures in the high gain antenna feed horns on both STEREO spacecraft will require corrective action in the coming months that will severely limit science operations. The high temperatures are being caused by the small angle between Earth and the Sun as seen from each spacecraft. In other words, pointing the antenna at Earth is putting too much solar heat on the antenna feed horn. To bring down the feed horn temperature, and preserve the spacecraft for years to come, the antennas will be pointed off at an angle from both Earth and the Sun, so that less heat will fall on the feed horns. Communication will still be possible using one of the antenna side lobes, but the telemetry rate will be extremely low. What instrument operations can be supported while the antennas are off-pointed is still being studied.

The original mission timeline was three years. They're a few months away from eight.