Archive for the Launches Category

SDO Launch Coming Soon! – Feb 3rd

Posted in Astronomy, Launches, Mission Operations, Observatories on 01/18/2010 by clairdeluna


The Solar Dynamics Observatory (SDO) is the next robotic scientific mission NASA will launch. Currently it is scheduled to launch from Cape Canaveral’s SLC-41 on an Atlas 5 rocket on February 3, 2010 with a one hour launch window (10:53-11:53 a.m. Eastern Time). The mission will nominally last for 5 years. After the success of the SOHO, STEREO, and TRACE missions, having another active solar observatory will be an incredible leap in capability for solar science.

And what a leap! SDO will have the fastest time resolution ever flown for solar imaging: 8 full disk images covering 8 different wavelengths every 10 seconds. This means SDO will generate an absolutely phenomenal amount of data. One major challenge for missions in orbit is finding a way to transmit large amounts of data to the ground. Often, spaceborne instruments are capable of generating much more data, but must choose to produce less so that the data storage and transmission requirements are met.

SDO’s solution to this issue is to place the observatory in a geosynchronous orbit over the White Sands ground terminal in Las Cruces, New Mexico. Geosynchronous orbits are special because the satellite orbits the Earth at the same rate that the Earth itself is rotating. These are the orbits used by the satellites that monitor weather, or provide your satellite TV. In this case, the geosynchronous orbit will allow SDO to have very long continuous communications directly with the ground. Direct link to the ground allows for transmission of more data per second than using data relay satellites. So this orbit absolutely maximizes the transmission rate for SDO.

Why does SDO need so much data? Well, because the mission is designed to perform very precise helioseismology measurements. Seismology, the study of how waves travel through an object, is used on Earth to study tectonic disturbances such as earthquakes and volcanos. For large, deep earthquakes, seismic measurements of such disturbances tell geologists much about the inner structure of the Earth. By using SDO to watch waves travel across the surface of the Sun, helioseismologists hope to gain similar knowledge of what is occuring deep below the Sun’s surface.

In fact, observations made from the ground have already demonstrated the feasibility of such science. But ground based solar observatories have significant disadvantages over orbiting spacecraft. For example, SDO will only experience nighttime twice each year, with each being about 3 weeks long. This means the rest of the year SDO will have non-stop viewing of the Sun, giving solar scientists an unprecedented dataset just as we start a new solar cycle.

In addition, SDO hopes to uncover much more about the solar magnetic cycle. After the long solar minimum we have just experienced, it is evident that our understanding of the Sun’s intrinsic magnetic field is still in its infancy. SDO’s monitoring of the Sun’s complex magnetic structure will give us an opportunity to better understand how it interacts internally and with the rest of the solar system; from sunspots, prominences, and coronal mass ejections from the Sun’s surface to solar wind and auroras experienced here on Earth.

I’m so excited to see what new science this observatory unlocks! Of course it still has to go through that last big leap to get it into orbit. Let’s just hope the rocket doesn’t blow up!


WISE Launching!

Posted in Launches, Observatories on 12/14/2009 by clairdeluna

Go check out the launch on NASA TV! (Now that the launch is complete, this link is no longer showing the WISE launch. However, you can watch the replay below.)

Update: Once again, despite my constant expectations, the rocket didn’t blow up! Don’t believe me? Here’s the replay…

Words have meaning: Hold (Hold Hold)

Posted in Launches, Mission Operations, Observatories, Word Meanings on 12/13/2009 by clairdeluna

The last few minutes of a launch are very critical. It is at this time that systems on the launch vehichle, and (for some missions) the payload, are switched from using an external power source to using their internal batteries. For Delta launches, this switch usually occurs four minutes before launch, and gives the final insight into the complete health of the system. At this point, if any data indicates a possible problem it is necessary to quickly stop the launch.

In mission operations, words that indicate a specific, time-critical action must be very precise. In this situation, the words used by an engineer to the launch director to stop the launch are:

Preparing to launch a multi-million to multi-billion dollar observatory requires practice. So the last six months prior to launch are filled with practices. “Mission rehearsals” that exercise the post-launch and activation process are very complicated, and are run repeatedly by the mission operations team. “Launch rehearsals” that practice the pre-launch process are performed jointly with the launch vehicle operations team several times before launch. During launch rehearsals, one of the hardest things for me to learn was never to say the word “hold.”

Saying “hold hold hold” only has consequences if you say it on the particular communications channel (voice loop) that is connected to the launch operations team, and I never had any reason to be on that loop. Even so, I spend the last few months finding alternative words to use. “Please carry this for me,” rather than “Please hold this.” “Can you wait a minute,” rather than “Can you hold on.” And the list goes on…

It seems like such an innocuous word, hold, until you realize that with that one word you have the power to stop a launch. And right before launch, even a one day delay is a LOT of manpower, and money. But that’s not nearly as painful as the investigation that would follow a failed launch.

You hope you never have to say “hold hold hold.” But if something’s not right, it’s absolutely the right thing to do…

WISE Launch Slips to Saturday

Posted in Launches, Mission Operations, Observatories on 12/11/2009 by clairdeluna

Note: As palmerin mentions below, the launch is now scheduled for Monday. Enjoy the free weekend! I bet the mission team is frustrated!

The WISE launch, originally scheduled for yesterday, has slipped to Saturday morning. The current WISE mission launch page indicates that the reason for the slip is a “problem with a booster steering engine.” Such a problem could range from relatively minor (two sensors giving incompatible readings) to serious (some hardware failure could make the booster unsteerable). But with a 24 hour hold, it’s probably a minor issue.

When your launch window is less than 14 minutes (6:09:33 – 6:23:51 a.m. PST for Saturday), you only get one shot at launching. The typical Delta-II recycle time (how long it takes to get a second try) is about 20 minutes. I’ve seen it done in 17 minutes, and that was very fast. If the problem requires more than a few moments to figure out, the launch is usually scrubbed (postponed) and rescheduled for a later time. How long they wait depends on the severity of the problem. The minimum time is however long it takes to get to the next launch window that will put the spacecraft into the proper orbit. For a mission like WISE, that time is probably 24 hours, hence the 24-hour delay.

Sadly, that means those of us who are launch junkies have to actually drag ourselves out of bed on Saturday morning if we want to watch the launch. But hey, at least we aren’t gonna have to work the weekend!

But the Aliens were Cooler!

Posted in Launch Failures, Launches, Test on 12/10/2009 by clairdeluna

Update: The failed launch has been confirmed as a Russian Bulava missile test.

This morning I posted about the Aliens Hypnotizing Norway. Via Spaceweather and Bad Astronomy come some useful updates.

First, there was a navigation warning issued for the area indicating that no one (let me repeat NO ONE) was trying to hide the fact that there was a launch test being performed. Second, another picture has emerged of the event:

The inset clearly shows a perfectly normal launch trail leading up to the more bizarre imagery that we have seen. This white trail has begun to dissipate, with differing winds at different altitudes pushing the trail around until it looks irregularly jagged. Anyone who has seen a successful launch on a clear day will recognize that trail.

At the top of the trail, there is a brighter spot and the trail itself ends abruptly. I suspect this is where the anomaly likely occurred. Having seen this picture, I will revise my earlier statements and say that the upward thrust probably ceased at this point. The remainder of the upward motion was simply from the rocket’s momentum. The blue trail is likely fuel venting from the first stage.

At the end of the blue trail, something changes. It could be that a second stage on the rocket ignited autonomously (most launches are run by an onboard script…you don’t want to have to try to command something that complex by hand), or simply that the torque got too large and created venting as I suggested before. Either way, the rotation had already been imparted to the system. Once there was some sort of thrust (engine firing, massive venting) the spiral started to form.

Anyone who says the system should have fallen to earth at that point needs to play with those spiral fireworks for a little bit. The push given by the tangential thrust may very well have kept the system rotating in what is a nearly stationary position. From some of the images the cloud is obviously three-dimensional. However it is clear that by the time the spiral started, very little of the rocket’s original forward momentum remained.

Words have meaning: Anomaly

Posted in Launch Failures, Mission Operations, Word Meanings on 12/09/2009 by clairdeluna

In these posts, I typically like to highlight words with very specific meanings that are used far too generally or improperly by the average person. However, the popularity of my Norway Spiral post has led me to another word, one which is used as a catchall by engineers. And a word that seems to imply much, while actually giving nearly zero information. I mean, of course:

In engineer-speak, an “anomaly” is anything that didn’t go the way you expected it to go. While we test this hardware over and over on the ground, and rehearse the expected launch and activation sequences repeatedly, sometimes things just don’t behave as you expect. This can be due to something catastrophic, like a mission-ending hardware failure, or something as simple as not getting telemetry when you expected. (This can happen due to a scheduling conflict giving access to the communication satellite you were planning to use to a different, higher priority, user.)

When things don’t work the way you expect, it must ALWAYS be documented (an issue/discrepancy/anomaly/pick-a-word report should be filed). If the reason for the anomaly is simple, this step is a formality. But good engineering practices means it should be done anyway. On the other hand, some anomalies, especially those that result in mission loss, will be investigated by a number of experts for as long as it takes to either 1) find the root cause and communicate it to the rest of the space industry, or 2) determine that the cause is unknowable due to lack of sufficient information.

The Columbia tragedy started out as an anomaly and was investigated for years, leading to significantly improved processes for monitoring orbiter health post-launch. And you can bet the Norway Spiral was a launch vehicle anomaly. We watch this video and chuckle at the network callout that “we have just had an anomaly…” True, that may seem like a gross understatement. But in an industry where words have very specific meanings, no other word can be used without implying more than simply “something didn’t behave as expected.”

So next time you hear about some “anomaly” occurring on your favorite spacecraft, remember: it could be anything…or nothing at all.

Aliens are Hypnotizing Norway!

Posted in Launch Failures, Launches on 12/09/2009 by clairdeluna

On Edit: I have posted an UPDATE to this topic.

Final Note: The failed launch has finally been confirmed as a Russian Bulava missile test.

Ever wonder what a failed launch looks like? Check this out. (Note that there is a video of the event at that site.)

Launch failures come in many flavors, from huge explosions to a simple failure to reach orbit (i.e. “crash”). At this point no nation is laying claim to this one, and experts are speculating about possible new atmospheric phenomena, etc. But to me, this looks like a launch gone bad, with the root cause occurring right at launch. Check out this picture:

See the squiggly blue line leading up to the spiral? “Experts” are speculating that it is leaked fuel from a rocket of some sort. I suspect it’s simply the emission from whatever thrust mechanism was used, and that a stabilization problem on the launch vehicle caused the rocket to spiral up rather than launch straight up. I have seen this effect before, and once the instability gets large enough to be obviously visible, it’s nearly impossible for the launch vehicle to self-correct.

This instability probably produced a significant torque on the entire system, finally rupturing something on the vehicle – essentially ending the upward thrust. It’s at that point that the real show starts. The instability that shows up in the blue corkscrew imparted a rotation to the system. This rotation, plus what appears to be venting from the rupture, is what produced this extraordinary spiral in the sky.

When you watch a launch you notice that as the rocket gets to higher and higher altitudes, the plume from the engine spreads wider and wider. This is due to a reduction in the density of the atmosphere. Lower density equals less air pressure equals wider plume. From the amount of spread seen in the vented material, the spiral appears to have occurred at a reasonably high altitude. Evidence for this is increased by the fact that photographs of the event from different locations (see here, here and here) show similar structure. If it was low, the viewing angles would be very different. But while you can see some differences in the spiral pattern, the same basic structure is visible.

It will be interesting to see who finally admits to having performed this launch. Alternately, I could be completely off base and it really is evidence of aliens trying to hypnotize Norway. But I wouldn’t bet on it…

Hat-tip to Spaceweather for the heads-up.