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Before NASA: When Jack Townsend met Dave Schaefer: Building the Vanguard telemetry system

November 8, 2011 Leave a comment
John Townsend in 2008.

John Townsend in 2008.

John (Jack) Townsend, one of the founders of NASA’s Goddard Space Flight Center, passed away on Saturday, October 29. Among many other things, Townsend helped to develop the Vanguard satellite program, before NASA even existed. That was a long time ago, but many people are still around who worked with Townsend in those days.

Dave Schaefer is such a man. About a year ago, it was my pleasure to make the short drive to Dave’s home in the leafy outskirts of Silver Spring, Maryland. I was accompanied by NASA computer scientist James Fischer, who, like Dave, spent decades developing Goddard’s high-performance computing capabilities.

Dave Schaefer stands by the rug in his home office woven with the image of Explorer 12, a spacecrft he helped to design.

Dave Schaefer stands by the rug in his home office woven with the image of Explorer 12, a spacecraft he helped to design.

Dave was a member of the team that developed an important component of the Vanguard satellite: the telemetry system, which captured data from the satellite’s sensors, stored it temporarily, and relayed it to Earth.

Vanguard began as a program at the Naval Research Laboratory in Washington and transferred over to NASA (along with many of its personnel) after the agency was founded by the National Aeronautics and Space Act of 1958.

Vanguard was the first civilian satellite program, established for the International Geophysical year of 1957.  “Vanguard was supposed to orbit the very first artificial satellite,” Schaefer says. “It had its troubles.” Sputnik took over the honor, in October 1957, of becoming the first artificial Earth satellite.

But years before Sputnik was even a gleam in the eye of the Soviet politburo, Dave Schaefer and fellow staff scientist Robert Rochelle went to work at the Naval Research Laboratory, helping to lay the foundations for the U.S. civilian space program. That was in 1949.

Dave and Jack first met later, in 1955. It was all because of a radio broadcast heard in a car bound for Kansas. Schaefer told us the story this way:

“I was out in Kansas coming back from having taken two cousins of mine out there, on this auto trip. It was 1955, and here we had the radio on, and here there was a broadcast and it said mankind was going to do the greatest, most wonderful thing that had ever been done!” he says, raising his voice to preacher tone for dramatic emphasis.

“We were going to orbit an artificial moon. My God! And this was going to be done at a place called the Naval Research Lab. Well, I was already working at NRL on magnetic amplifiers. I had been there since March in 1949.

“Well I went to Whitney Matthews, who was my boss’s boss, whose name should show up in the annals of Vanguard, and I said to Whitney, “Why are we working on stupid magnetic amplifiers when the greatest thing that mankind has ever done is being done two buildings down?” And I slammed the door. I could have been out of a job, but I wasn’t.

“So two days later Whitney came to me, he said, “I have invited someone from the satellite project over to talk to us. His name is John Townsend. Jack is going to come over and talk to us tomorrow afternoon.”

“So he arrived and he said, ‘We need a telemetry system.’ He said if we go out commercially to get it, it will weigh 20 lbs. We need one that weighs — I think he said four pounds or something. And he didn’t say a lot more. He said to us, “You all think you can do it?”

“And of course we said yes, yes, yes! We made sure he went down to the elevator. We made sure he was on his way back to his office two buildings down. Then you know what we did? We ran to the nearest dictionary to figure out what in heaven’s name a telemetry system, was!

“He’d said I’ll be back in a week to see how you’re doing.  He was back in a week, because of our knowledge of magnetics, our group had a telemetry system operating for him.  And it only weighed 8 ounces, including the batteries. It met the specs, and in fact it used so little power we didn’t need to turn it off at all.” Schaefer says Bob Rochelle was the main person responsible for this achievement.

Dave Schaefer points to the portion of the Vanguard electronics core he helped to build in the late 1950s. This was an actual working model of the electronics package built for the Vanguard satellites.

Dave Schaefer points to the portion of the Vanguard electronics core he helped to build in the late 1950s. This was an actual working model of the electronics package built for the Vanguard satellites.

The United States — with the help of Dave Schaefer, Bob Rochelle, Jack Townsend, and many other people — attempted 11 Vanguard launches from 1958-59. They achieved orbit three times.

The grapefruit-sized Vanguard 1, the world’s first solar-powered satellite, launched St. Patrick’s Day (March 17) 1958 weighed just 3.35 pounds. It remains the oldest artificial objects orbiting Earth to this day.  The Rochelle telemetry system flew on Vanguard 3, launched on September 18, 1959.  This satellite is slated to remain in orbit for 300 years.

That same year, 1959, Jack Townsend jumped ship to the new civilian aerospace program, NASA, and helped establish Goddard Space Flight Center, assuming the role of Assistant Director for Space Science and Satellite Applications.

The rest is history — our history at Goddard Space Flight Center, and the origins of the nation’s aerospace agency. As Schaefer wryly points out, “The Vanguard telemetry system, the results of a ‘dare’ of Jack Townsend’s, will be in space, remembering him, for 300 years.”

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.

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Fill'er up! Animation of NASA's robotic refueling mission

June 29, 2011 1 comment
Take me to your (out of fuel) satellite!

Take me to your (out of fuel) satellite!


Next week’s final launch of the space shuttle Atlantic will be bittersweet for all of us at NASA and for space fans the world over. It will be the end of something very, very big in many people’s lives, and in the life of the United States space program. Something to be proud of; something to mourn. STS-135 is an end and a beginning. I suspect there won’t be a dry eye in the house around here when she goes into orbit.

But for our part, Goddard’s going out in style. The shuttle Atlantis will deliver to the International Space Station a package of gear developed here in a fury of activity and inspiration and hard work over the past 18 months. It’s called the Robotic Refueling mission.

Tools and supporting gear bolted to the space station will, later in the year, allow astronauts operators using the Special Purpose Dexterous Manipulator (SPDM/Dextre) to explore an utterly new technology to repair or refuel satellites in orbit.

[Many thanks to NASA’s Alex Janas for clarifying how the tools will be used on orbit, and by whom. Dextre, the space station’s two-armed Canadian robotic “handyman,” will manipulate the tools developed at Goddard. Operations will be entirely remote controlled by collaborating teams of flight controllers at Goddard Space Flight Center, Johnson Space Center, Marshall Space Flight Center,  and the Canadian Space Agency’s control center in Quebec.]

The animation below says it all: NASA at its best: It seems-like-science-fiction-but-it’s-not.

On Tuesday last, gogblog tagged along on a media tour of the robotic refueling mission, led by veteran Goddard public affairs stalwart Dewayne A. Washington.

We met the brains and muscle behind the mission at the Building 7-10-15-29 complex, where many a great mission has been developed and tested. More details and photos in future posts……



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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.

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SDO first-light anniversary webtastic mashup: Here (again!) are all the images and videos in one place

April 21, 2011 4 comments

sdo image mosaic

Here is a one-stop-shopping collection of our efforts this week to celebrate the one-year “first light” anniversary of NASA’s Solar Dynamics Observatory.

Check out this “best of” compilation of video stunners from SDO’s first year at work and vote for your favorite. Voting is open until May 5. Pick the best SDO video of the year




They’re talking about us in Wales! At a meeting of the Royal Astronomical Society, researchers announced some new insights into what unleashed the powerful 2011 “Valentine’s Day” solar flare — with help from SDO.




Feast your eyes on this Flickr slideshow of SDO beauty shots.


flickr_image_475

And while you’re at it, see the past year of Solar Dynamics Observatory “pick of the week” beauty shots.




Did you miss the “Ask SDO” Twitter Q&A event on Tuesday? No problem: Experience the whole thing here on a Storify feature created by Goddard science writer Liz Zubritsky.


storify_image_475

A year ago, NASA scientists gathered to announce the first crop of amazing SDO images to the world. But you can still watch the press conference.


sdo_press_conf_475

Last but not least, browse the original SDO first-light image releases a year ago on the Goddard SDO website.


sdo_website_image_475
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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.


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Goddard's First Homegrown Satellite, Explorer 10, Was Launched 50 Years Ago Today: We Talk to the Father of Explorer 10, James Heppner, About the 'Opportunity Years' at the Dawn of NASA


photo of Earl Angulo (at left) and Ron Browning examining an Explorer-10 model attached to a test fixture
This photo from the early 1960s shows Goddard employees Earl Angulo (at left) and Ron Browning examining an Explorer 10 model attached to a test fixture. They were responsible for the mechanical engineering and testing of the satellite.


Fifty years ago today, Goddard’s first homegrown scientific satellite roared off the pad at Cape Canaveral on a Thor-Delta rocket. Although key components came from outside the gates, Explorer 10 was the first satellite to be designed, assembled, tested, and flown from Goddard Space Flight Center.

James Heppner, a young space physicist (barely 30 then) and one of NASA’s early employees, conceived of the mission that came to be called Explorer 10. Heppner functioned as a sort of one-man band — Project Manager, Project Scientist, and Principal Investigator for the magnetometer instruments on the satellite.

Before NASA was founded, Heppner worked for the Naval Research Laboratory (NRL) on the Potomac River in Washington, D.C. It was there he developed methods to measure Earth’s magnetic field. At NRL he used sounding rockets to study charged particles and magnetic fields high in Earth’s atmosphere. His earlier research in Alaska focused on the aurora and its effects on radio wave propagation, and was the basis for his Caltech PhD thesis.

Heppner calls these times the “opportunity years,” a period when methods and technology for measuring magnetic fields and space plasma — the bread and butter of space physics — were being invented. He was at the right place at precisely the right time.

In late 1958, as Heppner and many of his colleagues were being “handed over” to the nation’s new aerospace agency, he had already helped create a magnetometer for the Vanguard program. Vanguard, an NRL project, was created to loft the first civilian scientific payloads into space for the International Geophysical year of 1957-58. Heppner’s proton magnetometer went into space aboard Vanguard 3 on September 18, 1959.

NASA satellite P-14 was renamed Explorer 10

NASA satellite P-14 was renamed Explorer 10

At the time of the transition to NASA, Heppner today recalls, he conceived of a satellite to measure the magnetic field of the moon. The mission, then called P-14, would accomplish its goal by extreme measures:

“I originally proposed Explorer 10 when NASA was formed,” explains Heppner, 83, who spoke with me recently from his home in New Market, Maryland. “And the intent was to try to hit the moon and measure the moon’s magnetic field on the way in.”

The original plan was deferred. The truth is, hitting the moon — even intentionally — was no simple trick in those days. It wasn’t clear the Thor-Delta launch system would accomplish the task, and even tracking a spacecraft to the moon was straining the technical capabilities of the time.

“With time we realized that the odds of hitting the moon would be extremely low, from the vehicle performance and ability to track, things like that,” Heppner explains. “I was told that with the odds of hitting the moon being so low, it would be embarrassing to even try. So I was essentially directed by NASA headquarters to make sure that the trajectory was such that it couldn’t be interpreted as an attempt to hit the moon.”

The new mission goal was to measure magnetism and plasma particles in space from outside of Earth’s protective magnetic bubble, or magnetosphere. This had been attempted previously, but not with great success. To do it required launching P-14/Explorer 10 into a highly elliptical orbit that would take it a great distance from Earth, dozens of time the planet’s radius.

The satellite weighed approximately the same as a space physicist: 79 kilograms, or 178 pounds. “It was very light,” Heppner says. “We were trying to get distance.” An engineering model hangs in the Smithsonian if you care to look at the real thing..

For the records, here is the complete entry in the NASA/National Space Science Data Center mission database:

“Explorer 10 was a cylindrical, battery-powered spacecraft instrumented with two fluxgate magnetometers and one rubidium vapor magnetometer extending from the main spacecraft body, and a Faraday cup plasma probe. The mission objective was to investigate the magnetic fields and plasma as the spacecraft passed through the earth’s magnetosphere and into cislunar space. The satellite was launched into a highly elliptical orbit. It was spin stabilized with a spin period of 0.548 s. The direction of its spin vector was 71 deg right ascension and minus 15 deg declination. Because of the limited lifetime of the spacecraft batteries, the only useful data were transmitted in real time for 52 h on the ascending portion of the first orbit. The distance from the earth when the last bit of useful information was transmitted was 42.3 earth radii, and the local time at this point was 2200 h. All transmission ceased several hours later. “


On March 25, 1961, a rocket similar to this one launched Explorer 10 into space. This historic Delta rocket stands in the Goddard Visitor Center's "rocket garden." (Image: Wikipedia RadioFan)

On March 25, 1961, a rocket similar to this one launched Explorer 10 into space. This historic Delta rocket stands in the Goddard Visitor Center's "rocket garden." (Image: RadioFan)

Rubidium vapor magnetometers could measure extremely weak magnetic fields, and were a totally new technology, Heppner says. They were invented at a company called Varian Associates in Palo Alto, California. The Faraday cup plasma instrument, which measured particles streaming off the sun’s “solar wind,” came courtesy of a team of scientists at MIT led by the pioneering X-ray astronomer and plasma physicist Bruno Rossi.

Finally the big day came on March 25, 1961. The launch managers for the Thor-Delta rocket worked in “the block house” at the Cape, while Heppner and his colleagues were encamped in a machine shop, peering at oscilloscopes to assess the health of their satellite and staying in contact with the blockhouse, and the other scientists and engineers, by telephone.

Explorer 10, as was typical in those days, was powered by a expendable battery. The craft radioed back data for 52 hours as it swooped through and outside of the magnetosphere, travelling for 42.3 Earth radii — about 167,466 miles — before the battery dimmed and the craft shut down. (For comparison, consider that the average distance form Earth to the moon is 238,857 miles.)

After launch, tracking stations record data on tapes and send them to the scientists. Heppner published a number of scientific papers from the data. He headed the Goddard Magnetic Fields Group, and worked on many major missions over the succeeding years.

The next big missions for Heppner after Explorer 10 were the Orbiting Geophysical Observatories, which grew substantially in mass and capability. He retired from the civil service in 1989, but continued to work as a contractor until 1996.

How were those days different from the later, larger, more complex place NASA has become? What was it like in the opportunity years?

“It was a very busy period in the sense that the technology was developing,” Heppner explains. “The early satellites weren’t very sophisticated because everything was new.”

But things moved fast. Heppner summed it up best in a chapter he wrote for a 1997 book, Discovery of the Magnetosphere.

“Opportunities for new endeavors were plentiful and the time between conception and results was unbelievably short when viewed in the light of today’s space programs.”

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.

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That Was the Week that Was, March 14-18, 2011. . . Best of Goddard People, Science, & Media and the blogpodcastotwittersphere


Tsunami Damage, Rikuzentakata, Japan

Tsunami Damage, Rikuzentakata, Japan


Japan Earthquake
After the March 12 earthquake and tsunami in Japan, it’s as if the world collectively gasped — and then what followed was almost a feeling of disbelief as the harsh facts begin to register. Entire seaside communities erased from existence. . . tens of thousands of lives feared lost. . . giant ocean swells flooding the coastline. . . cars and houses looking like toys bobbing in the water. And then there are the satellite images, which provide a critical wide-angle perspective.

NASA’s Earth-observing fleet has helped to reveal the full scope and power of the catastrophe. As Mark Imhoff, the Terra satellite project scientist at Goddard, said in a report by West Virginia Public Broadcasting:

“It’s been heart wrenching seeing some of these images because the first set images that we got in on the day after the earthquake on March 12, even though the resolution from of the satellite wasn’t very good, the data from the Miser instrument at Jet Propulsion’s Laboratory showed that there were a large area of coastline that really weren’t there anymore and so you could really get an impression that a lot of villages and agricultural areas had really been severely impacted by the ocean.”


NASA released a web feature on March 17, five days after the quake, showing tsunami after-effects documented by Landsat 7.

NASA Earth Observatory has compiled a gallery of earthquake-related images from various NASA spacecraft, including EO-1, Terra, Aqua, and astronaut photos from the International Space Station.

As usual, EO’s in-depth captions provide context and explanations for the various destructive effects of the earthquake on coastal Japan. An even larger selection of imagery is available in this NASA web feature about the disaster.


lola_trio_600

New LRO Data
On March 15, the Lunar Reconnaissance Orbiter mission released the final set of data from the mission’s exploration phase, along with the first measurements from its new life as a science satellite. The press release explains the details. The slideshow below takes a look back at some of the coolest imagery from the mission so far. All the images in the slideshow, and many more, are archived here on the NASA LRO website, which includes detailed captions.




Messenger Makes It
The third major story out of Goddard this week was the arrival in Mercury orbit of the Messenger spacecraft. After three spectacular fly-bys earlier (see slideshow below), Messenger is now in position to really dig into its science mission to reveal the nature and history of the first rock from the sun. An earlier post discusses some of the research being conducted on Mercury’s thin “exosphere” of atoms and ions wispily clinging within the planet’s gravity.


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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.


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Why understanding something smaller than a pinprick (an aerosol particle) is the key to something as big as a planet (global climate)

February 23, 2011 Leave a comment

UPDATE MARCH 4: Sadly, Glory launched this morning but did not reach orbit because the payload faring did not separate. The faring protects and encloses the satellite during launch and initial ascent. With this extra weight onboard, the launch system was unable to reach orbit and landed in the ocean. Condolences to the mission team that spent years designing and building the ill-fated Glory spacecraft.


mosaic of images and art associated with glory mission

To learn anything, you first need to know what you don’t know. Let’s call them the “known unknowns.”

In climate science, one of the thorniest known unknowns is the impact of aerosols, microscopic particles that drift in the atmosphere absorbing and reflecting energy, and tweaking clouds. My colleague Adam Voiland — Goddard Space Flight Center’s chronicler of all things aerosol — explained it this way in one of his many fine web features and press releases on the topic:

“The particles can directly influence climate by reflecting or absorbing the sun’s radiation. In broad terms, this means bright-colored or translucent aerosols, such as sulfates and sea salt aerosols, tend to reflect radiation back towards space and cause cooling. In contrast, darker aerosols, such as black carbon and other types of carbonaceous particles, can absorb significant amounts of light and contribute to atmospheric warming.”



The Glory mission, which is scheduled to go into orbit this week, will attempt a much better understanding of aerosols and — climatologists hope — lead to needed improvements in the computer simulations that predict where earth’s climate is heading in the coming decades.

But for my part, the Glory mission actually takes me back a decade or so, to the mid-1990s when I worked for a now-defunct science magazine called Earth. The UN’s Intergovernmental Panel on Climate Change (IPCC) had, in 1995, published its Second Assessment Report. Using a newfangled thingie called the World Wide Web, science reporters eagerly poured over the IPCC report’s many hundreds of pages, trying to make sense of it all.

One issue that stood out was — you guessed it — the role of aerosols in global climate change. Here’s what the panel authors said on page 525 of a portion of the IPCC report, Working Group I: The Science of Climate Change.

“Atmospheric aerosols (Chapter 2) also play an important role in the Earth’s radiative budget. There are fairly reliable estimates of the amount of sulphur burned but these do not translate directly into number density of aerosols, for which the size, hygroscopic and optical properties, as well as their vertical, horizontal and temporal distributions, have not been well observed.”



Allow me to translate: It’s saying that we know how much sulfur-containing fuels we burn (coal, for example), which produces sulfate particles that have a cooling effect on climate; but that doesn’t tell us how much of this aerosol is produced, how much energy it reflects, and where it is.

And on page 526, the report tells us why we should care about aerosols, from a practical point of view:

Thus, at present the uncertainty in aerosol radiative forcing is the largest source of uncertainty in the total radiative forcing of climate over the past industrial period. Since aerosols are very patchy in their distribution, they could create significant regional climate changes regardless of their effect on globally averaged forcing.



{If you have a lot of time on your hands or need something very heavy to hold doors open, download and print Working Group I: The Science of Climate Change by clicking HERE.}

So here is the punchline for this week: Glory will provide data needed to help resolve uncertainties about aerosols and climate. The hope is that computer models will be able to make better predictions of where Earth’s climate is heading.

If you want to learn more, here is a series of recent videos about the Glory mission. And don’t miss this and this web feature about Glory, by Adam Voiland.






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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.

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Phil Evans' Swift Universe: Contemplating the inconstancy of the Crab

January 12, 2011 Leave a comment

New results from NASA space observatories have revealed something surprising about the Crab Nebula: This famous supernova remnant — long considered a veritable “old faithful” of X-ray sources for the constancy of it energy output — appears to be dimming over time. We asked Phil Evans, gogblog’s on-call X-ray scientist and a member of the NASA Swift Observatory science team, to tell us why the inconstancy of the Crab is so important to astronomers.

image of crab nebulaThe Crab Nebula has a prestigious history. It formed when a star exploded in a supernova, and was first observed and recorded by Chinese observers in 1054 AD. The glow of the supernova was so bright, people could see it during the day for more than 3 weeks!

The material which was blown off the star has been expanding since then in a complex structure with leg-like filaments that earned it its name. It’s also a very bright source of X-rays, and — particularly usefully — its brightness and spectrum don’t change; so astronomers can (and do) use it to calibrate their X-ray instruments. In fact, “a Crab” is an internationally recognized unit of measurement.

The problem is, these new results suggest that the Crab is not constant after all, according to a press release issued today by NASA’s Goddard Space Flight Center. The measurements taken over the last few years by the Fermi, Swift, RXTE and INTEGRAL satellites show that the Crab actually varies by a few percent every year. This is not too disastrous right now: It’s pretty hard to calibrate high-energy instruments to an accuracy of 1 percent or so, and the definition of “a Crab” as a unit of measurement has a fixed definition. But as technology advances, we will probably find that the Crab is no longer the ideal calibration source.

This type of finding, by the way, is not unusual. It is often the case that an object described as the “protoype” of its class turns out to be atypical! Indeed the star Vega, long used as a standard in optical astronomy, was recently found not to be standard. The exciting thing about all of this is it shows us how much we still have to learn. The Crab is among the brightest X-ray sources in the sky, and yet it is able to jump out and surprise us.

In a related point under the same press release, recently published work from the NASA’s Fermi Gamma-ray Space Telescope and the Italian Space Agency’s AGILE satellite have found large gamma-ray flares from the Crab Nebula. Investigation is ongoing, but this may indicate a really strong electric field. As study coauthor Stefan Funk said, “The strength of the gamma-ray flares shows us they were emitted by the highest-energy particles we can associate with any discrete astrophysical object,” which in themselves present plenty of challenges.

The Crab nebula: exciting and enigmatic? Yes! Constant and well understood? No! A fantastic natural laboratory? You bet.

— Phil Evans

Follow Phil on Twitter to get updates on his life and work in X-ray astronomy.
@Swift_Phil

chart of declining crab nebula x-ray output

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.


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Happy 15th birthday, SOHO

December 2, 2010 Leave a comment
The top 10 favorite SOHO solar images chosen by the public in 2005

The top 10 favorite SOHO solar images chosen by the public in 2005


Takes a licking, keeps on ticking — you could say that about a lot of “birds” developed at Goddard Space Flight Center. SOHO, the Solar and Heliospheric Observatory, is one of them.

On December 2, 1995, SOHO blasted into space from Cape Canaveral. The joint European Space Agency/NASA project soon began its work observing the sun. If you want to know the how, whats, and whys, please read the excellent press release by my colleague Karen Fox and the a short feature on The Sun Today website. Or browse the latest SOHO imagery of the sun.

But here are the take-homes:

  • “Fifteen years later, SOHO has revolutionized what we know about the solar atmosphere and violent solar storms produced by the sun.”
  • “SOHO has become an expert comet-hunter…”
  • “…helped create the field of near-real-time space weather reporting as we know it…”
  • “Placed into orbit around the L1 Lagrangian point between Earth and the sun, SOHO was able to observe the sun continuously without Earth ever obstructing its view.”
  • “SOHO is perhaps best known for its observations of coronal mass ejections, or CMEs.”
  • “…as of November 1, 2010, SOHO had spotted more than 1,940 [comaets.] (A contest to predict the day on which the 2,000th will be spotted is here.)”
  • “The Solar and Heliospheric Observatory or SOHO is by many accounts the granddaddy of modern solar astronomy.”

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.

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Happy birthday, EO-1. . . Ten years and a day ago, the first Earth observing satellite of the New Millennium program launched into orbit

November 22, 2010 Leave a comment
EO-1 satellite image of the World Trade Center in flames on 9/11

EO-1 satellite image of the World Trade Center in flames on 9/11

EO-1 logoOn November 21, 2000, a satellite called Earth Observing 1 (EO-1) was launched on a Delta rocket from Vandenberg Air Force Base. It was the first satellite in NASA’s New Millennium Program Earth Observing series.

***UPDATE: If you are interested in the science EO-1 has delivered for the past decade. check out the outstanding feature article on NASA Earth Observatory. It also includes many more images from EO-1.***

EO-1’s job was to test and validate new technologies that could be used in future Earth-observing spacecraft. For example, EO-1 went into orbit with a special antenna that uses no moving parts and instead uses software to steer the data beam back to the Earth antenna, and at very high data rates.

EO-1 also has a souped up solar array to produce more than twice the power per square inch than a typical array at that time. EO-1 also tested a reliable, lightweight electromagnetic thruster. And the spacecraft demonstrated the ability to fly in close formation with another Earth-observing satellite, Landsat-7. These are just some of the revolutionary satellite technologies on EO-1.

Engineering better satellites is important, but in the past decade EO-1 has also beamed down some pretty spectacular images of our planet. Here are a few.

The dense urban core of the District of Columbia

The dense urban core of the District of Columbia


Pearl Harbor, Hawaii

Pearl Harbor, Hawaii


The Alaskan interior

The Alaskan interior


The Aspen Forest Fire near Tuscon, Arizona in 2003

The Aspen Forest Fire near Tuscon, Arizona in 2003

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA. //
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Gogblog vodcast #2: Watch an Atlas 5 launch of a military satellite from Goddard's Flight Dynamics Facility

September 27, 2010 1 comment

One recent Saturday in August, I woke at 4:30 a.m., rubbed my eyes in the early morning darkness, and headed for Goddard Space Flight Center to watch the launch of an Atlas 5. The rocket blasted off from Cape Canaveral in Florida, carrying a military communications satellite into high geosynchronous orbit.

My perch: the Flight Dynamics Facility, which I described in an earlier post about FDF’s support of Shuttle and Space Station missions.

The FDF operations area is a large room packed with computer workstations. The mission of the FDF is to provide precise pointing coordinates to enable ground stations and satellites to track launch vehicles like the Atlas V into space. FDF also pitches in to track the Shuttle orbiter and the Space Station in low-Earth orbit to maintain links to the ground.

This video, with voiceover by FDF junior systems engineer Jason Laing, explains some of the major events in the launch of the Atlas V:

http://www.youtube.com/v/XRKWewWDP_E?fs=1&hl=en_US

Today the Atlas will carry the Advanced Extremely High Frequency (AEHF) satellite, the first of three. The system will provide secure global military communications between ground, sea, and air.

Start of show: I got in at around 6 a.m. and met the lead engineer for this launch, Syed Hasan. Bleary-eyed but alert, he got in at 12:30 a.m. to begin check-outs of the computer and communications systems. By Syed’s side for the launch: James Cappellari. A nearly 50-year veteran of NASA, Cappellari helped to develop and implement the Space Network. I deposited the obligatory bucket of donut-like objects in the FDF break room and got ready for “start of show.”

Start of show in the FDF is 10 minutes before launch, which today is slated for 7:07 a.m. At start of show, a TDRS satellite hovering above the U.S. East Coast will start tracking the Atlas right on the pad. Today it is TDRS 10, but TDRS 4 is also available for East Coast launches.

artist concept of the AEHF satellite

The AEHF satellite

FDF’s partner in this and other launches is the White Sands Complex in New Mexico, which controls the satellites comprising NASA’s Space Network. Eight TDRS satellites currently provide global tracking, communications, and data links for manned and unmanned spacecraft. When rockets phone home, it is often via the TDRS network.

About the time I arrived at FDF, Syed sent something to White Sands called an autothroughput test vector. This tests the system that would allow FDF to send pointing data directly to the TDRS satellites during launch, bypassing White Sands.

But that would only happen if the satellites drifted off their targets and needed to be repointed. Throughout the launch the ELV (expendable launch vehicle) team at FDF watches to make sure the satellites are pointing at the rocket and able to track it accurately. FDF supports 10 to 15 ELV launches per year.

The rocket “talks” to the ground via data links, so accurate pointing is important. During Space Station missions, accurate pointing of TDRS’ high bandwidth antennas allows astronauts and cosmonauts to wave hello to us earthlings via video downlink. Scientific spacecraft also use TDRS to pipe data to the surface on a regular basis. Without accurate pointing of the TDRS satellites, NASA’s operations in low-earth orbit would be much more limited.

photo of Syed Hasan and James Cappellari

Syed Hasan (left) and James Cappellari

As lead engineer on the ELV team today, Syed runs some FDF software called acquisition data generator, which he would use to create and send a pointing correction vector during launch, if needed. Rows of numbers on his monitor allows Syed to keep an eye on the actual “beam angles” of the TDRS antennas indicating what direction they point.

But FDF now has another tool in their kit for making sure the Space Network is on target. It’s called the SN Beams Display, and it was developed by FDF engineers with a combination of commercial and in-house software code. Today, FDF’s John Bez is manning the SN Beams.

The SN Beams creates a live view of the spacecraft from pad to orbit as well as the TDRS “beams.” Each beam is a cone of space, rendered in green or white, that indicates the position and coverage of the antenna. When a launch vehicle or satellite leaves the beam, it is out of range to that particular satellite, and another in the network must pick up the tracking — sort of like relay racers passing the baton.

During launches, the SN Beams provides visual clues to the FDF about the difference between where each satellite is supposed to be pointing (green), based on pre-calculated pointing data, and where the satellites are actually pointing (white).

Two other members of the team, Eric Smith and Jason Laing, are on hand to check the position of the launch vehicle at several key stages of the launch based on actual telemetry data from the rocket. For this they use two terminals running the “LRP” software, for Launch Reentry Processor. If the craft is not where it’s supposed to be, it might be necessary to adjust the pointing data for the TDRS satellites.

Here is a video of the launch of the AEHF rocket! This is video from the launch contractor, ULA:

http://www.youtube.com/v/eqymxhJCEU0&hl=en_US&feature=player_embedded&version=3

Atlas away! The magic moment finally comes at 7:07 a.m., when the Russian-made RD-180 main engine roars to life, supplemented by four solid rocket boosters strapped onto the first stage.

10…9…8…7… you know the rest. There is something about a countdown that is thrilling. It’s a high-stakes game when you launch a multi-billion dollar satellite. There is little room for error.

The early events happen quickly.

At 1:40 into the launch the SRBs cut out; 16 seconds later they jettison. The SN Beams shows this in detail, as three little cartoon SRBs pop off the Atlas V booster and fall into the video game Atlantic Ocean. The live feed from Florida just shows the brilliant plume of the rocket receding into the blue sky.

At 3:27 the faring on the front of the Atlas pops open like two clamshells, exposing the satellite mounted to the top of a Centaur second-stage booster. The main engine is still burning.

At 4:17 the main engine shuts down, an event FDF people call MECO (“mee-koe”), for main engine cut-off. After a short coast, the second stage “Centaur” fires up.

photo of engineers in FDF during atlas launch

Light that candle!

At 14:08, the Centaur shuts off and the vehicle coasts for almost 8 minutes. Then, at 22:17, it fires up again for about 5 minutes to accelerate the satellite into the higher geosynchronous orbit. The Centaur will cut out and finally release the AEHF satellite 51 minutes into the launch.

Two hours after launch, it’s “end of show” for the FDF. At this point, FDF no longer has responsibility for supplying pointing data to White Sands. However, they continue to monitor for some time, just in case their services are needed.

Big fat planet: I have to say, watching this all on the SN Beams was a real surprise to me, because it shows just how huge Earth is and how puny even the mighty Atlas V is in comparison. After the rocket had been blasting away furiously for almost five minutes, it was still barely over the Atlantic Ocean, heading east.

At 10 minutes, the launch vehicle was screaming through the atmosphere at more than 15,000 mph, the Centaur was still firing. After 20 minutes, the craft was barely over West Africa. At the moment the satellite was released, 51 minutes into the launch, it hadn’t completed a single orbit yet.

This tells you that Earth is BIG and massive. Escaping its gravity to a geosynchronous altitude of 22,500 miles requires a lot of fuel and a lot of time.

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.

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