Author Archives: Gray Rinehart

For Want of a Hyphen, the Spacecraft Was Lost

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Fifty years ago today — July 22, 1962 — an Atlas Agena rocket launched from Cape Canaveral, carrying the Mariner 1 spacecraft.


(Artist’s conception of Mariner 1. NASA image.)

Mariner 1 was intended to fly by the planet Venus. The flight was nominal

until an unscheduled yaw-lift (northeast) maneuver was detected by the range safety officer. Faulty application of the guidance commands made steering impossible and were directing the spacecraft towards a crash, possibly in the North Atlantic shipping lanes or in an inhabited area.

Range safety destroyed the vehicle 4 minutes and 53 seconds into the launch.

The launch failure investigation found two apparent causes. First, the “Atlas airborne beacon equipment” did not operate properly. In addition,

the omission of a hyphen in coded computer instructions in the data-editing program allowed transmission of incorrect guidance signals to the spacecraft. During the periods the airborne beacon was inoperative the omission of the hyphen in the data-editing program caused the computer to incorrectly accept the sweep frequency of the ground receiver as it sought the vehicle beacon signal and combined this data with the tracking data sent to the remaining guidance computation. This caused the computer to swing automatically into a series of unnecessary course corrections with erroneous steering commands which finally threw the spacecraft off course.

Anyone who has done any computer coding knows how critical even a single character can be. In this case, it cost an entire spacecraft. The Venus flyby would have to wait.

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What I Believe About What You Believe

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When our beliefs differ, and they often do, and especially when we clash over our beliefs, it’s good for you to know what I believe about what you believe.

I believe that you have the right to express what you believe.

I believe that you believe that what you’re telling me is good and true and right.

I don’t believe that your belief obligates me to believe the same thing.

I believe that I have the right to express what I believe.

I don’t believe that you must believe what I believe, even if I believe it’s good and true and right.

I believe that we should express our beliefs thoughtfully, respectfully, and politely.

I believe that we can converse, be acquainted, and maybe be friends, even if we believe different things.

But if you believe that I must believe what you believe, then I hope we can at least part on friendly terms.

___


(Punctuation makes a difference, I think.)

I guess this post is my way of trying to take responsibility for my own beliefs. That’s hard enough without trying to take responsibilty for anyone else’s.

Respectfully submitted,
G

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Lunar 'Explorer' Launched

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Forty-five years ago today — July 19, 1967 — Explorer 35 launched from Cape Canaveral on a Thor-Delta rocket.


(Explorer 35. NASA image.)

Explorer 35 was designed to study the solar wind — specifically, “the interplanetary plasma, magnetic field, energetic particles, and solar X rays” — in the vicinity of the Moon.

According to this mission page, the Explorer 35 launch was the 50th Thor-Delta mission — quite an accomplishment for the launch vehicle team.

Explorer 35 entered its elliptical lunar orbit on July 21st and began six years of observations. The spacecraft “found that the Moon has no magnetosphere, enabling the charged particles of the solar wind to hit the lunar surface,” and effectively creating a “cavity” in the solar wind. It was finally turned off on June 24, 1973.

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Yes, You Can Nominate for the Pegasus Awards … But Not For Long

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Nominations for the Pegasus Awards close in less than two weeks!

The Pegasi are annual awards for filk — generally, folk music with science fiction or fantasy elements — given by the Ohio Valley Filk Fest. Categories include Best Song, Best Classic Song, Best Writer/Composer, and Best Performer, plus two special categories for this year: Best Gaming Song and Best Travel Song.


(Pegasus Award logo.)

I submitted my nominations yesterday. Here’s the online nomination form, if you’re ready to go.

Unsure whether you can nominate? You probably can.

First, you don’t need to be a member of the filk festival itself to nominate or vote. That said, according to the official rules “the purpose of the Nominating process is to poll members of the filk community for their independent opinions of each category.”

Unsure whether you’re a member of the filk community? The rules cover that, too:

Anyone who exhibits an interest in the filk community can be considered a filker. Exhibiting interest can be shown by, but is not limited to:

  • Filking at sf/fantasy conventions
  • Attending filk conventions
  • Attending house sings
  • Participating in online boards/discussions/mail lists/webrings pertaining to filk
  • Discussing filk and filk related issues with other filkers

That last category is pretty broad, but if you and I ever discussed filk in one way or another then it seems as if you’re in.

Curious about what songs, songwriters, and performers are available to be nominated? The friendly folks at OVFF ran a “Brainstorming Poll” to take suggestions for each category; check it out for recommendations, or just to get a feel for the wide variety of filk and filkers. (Something of a shameless plug: As I blogged when the brainstorming results came out, my original song “The Monster Hunter Ballad”* was suggested in the “Best Song” category. Surprisingly, I was also suggested in the “Best Performer” category.)

Who did I nominate? I don’t usually nominate-and-tell (or vote-and-tell), so I won’t go into it category-by-category here on the blog. I will say it was hard to narrow down the choices! In the end, I nominated a number of different people, and some more than once, including Danny Birt, Alex Boyd, Tally Dueshane, Jonah Knight, Michael Longcor, Mikey Mason, Madison Roberts, Carla Ulbrich, and Scott & Kirsten Vaughan (aka The Blibbering Humdingers). Contact me directly and I’ll tell you exactly who I nominated for what.**

So, ready to nominate now? Once again, here’s the online nomination form. You have until midnight on July 29th — go for it!

___
*Inspired by the series of books by Larry Correia. (Full disclosure: I work for Baen Books, which publishes the Monster Hunter novels.)
**And, if you ask nicely, I might also tell you which of my other songs fit the special categories.

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A New Generation of Environmental Monitoring Capabilities

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Thirty years ago today — July 16, 1982 — Landsat 4 launched atop a Delta rocket out of Vandenberg AFB.


(Landsat 4. NASA image.)

Though it was the fourth in the Landsat series of spacecraft, Landsat 4 “was a major step forward in global remote-sensing applications.” According to this NASA page,

In addition to the Multispectral Scanner System (MSS) instrument, Landsat 4 (and Landsat 5) carried a sensor with improved spectral and spatial resolution, i.e., the new satellites could see a wider (and more scientifically-tailored) portion of the electromagnetic spectrum and could see the ground in greater detail. This new instrument was known as the Thematic Mapper (TM).

The Landsat 4 TM instrument had seven spectral bands. Data was collected from the blue, green, red, near-infrared, mid-infrared (2 bands) and thermal infrared portions of the electromagnetic spectrum.

The Thematic Mapper was an important addition to the environmental monitoring instrumentation, and later Landsat spacecraft carried improved versions of it.

Landsat 4 was designed to operate for 3 years. Although some of its components failed, it continued to operate in a limited capacity until 1993. Thereafter, the spacecraft sent telemetry data until 2001, when it was decommissioned.

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An Ill-Fated Lunar Surveyor

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Forty-five years ago today — July 14, 1967 — an Atlas Centaur launched from Cape Canaveral carrying Surveyor 4.


(Sinus Medii, planned landing site for Surveyor 4, imaged in 1994 by Clementine. NASA image from Wikimedia Commons.)

Surveyor 4 was scheduled to touch down on the lunar surface on July 17th, but …

After a flawless flight to the moon, radio signals from the spacecraft ceased during the terminal-descent phase … approximately 2.5 min before touchdown. Contact with the spacecraft was never reestablished, and the mission was unsuccessful.

The original landing target was 0.4 N, 1.33 W in Sinus Medii (“Central Bay”). Surveyor 4 may have exploded before impact, as this site notes that “communications were abruptly lost 2 seconds prior to retrorocket cutoff.”

So, like its sister ship Surveyor 2, Surveyor 4 did not accomplish its mission. Good thing there were seven spacecraft in the series!

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First Private ComSat, and Closest Comet Encounter

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Fifty years ago today — July 10, 1962 — Telstar 1 launched from Cape Canaveral on a Delta rocket.


(Telstar 1. NASA image from Wikimedia Commons.)

Telstar 1 was built by AT&T Bell Telephone Laboratories, making it the first privately-built communications satellite, and broadcast the first live television signals between the U.S. and Europe. The spacecraft was short-lived — its “command channel began to behave erratically” in November and its transmitter failed in February 1963 — but it proved the concept and thereby led to the worldwide satellite communications we enjoy today.

In other space history, on this date 20 years ago, the Giotto probe made a flyby of Comet Grigg-Skjellerup, passing the comet’s nucleus at a distance of between 100-200 km (62-124 mi). It was Giotto’s second flyby, having studied Comet Halley on its primary mission, and the closest-ever flyby of a comet nucleus.

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A Martian 4th of July Sojourn

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Fifteen years ago today — July 4, 1997 — Mars Pathfinder, which launched in December 1996, landed on Mars.


(“Twin Peaks” imaged by Mars Pathfinder. NASA image.)

Mars Pathfinder consisted of a lander, named the Carl Sagan Memorial Station after touchdown, and the Sojourner rover.

From landing until the final data transmission on September 27, 1997, Mars Pathfinder returned 2.3 billion bits of information, including more than 16,500 images from the lander and 550 images from the rover, as well as more than 15 chemical analyses of rocks and soil and extensive data on winds and other weather factors. Findings from the investigations carried out by scientific instruments on both the lander and the rover suggest that Mars was at one time in its past warm and wet, with water existing in its liquid state and a thicker atmosphere.

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Cometary Mission, Presumed Lost, and a Long-Lasting Solar Explorer

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Ten years ago today — July 3, 2002 — a Delta II rocket launched from Cape Canaveral carrying the CONTOUR (Comet Nucleus Tour) spacecraft.


(Artist’s conception of CONTOUR. NASA image.)

CONTOUR operated nominally for six weeks until it started the orbital escape maneuver that would take it away from Earth.

The spacecraft was scheduled to ignite its STAR 30 solid rocket engine on 15 August 2003 at 08:49 UT (4:49 a.m. EDT). This firing was to take CONTOUR out of Earth orbit and put it on a heliocentric trajectory. However, following the scheduled firing time, no further contact was made with the craft. Telescopic surveys were made under the assumption that the firing took place on schedule, and three objects were identified near the expected position of CONTOUR, leading investigators to believe that the firing took place and that these objects were parts of the spacecraft and rocket engine. An investigation board concluded that the most likely cause of the mishap was structural failure of the spacecraft due to plume heating during the solid-rocket motor burn. Alternate possible but less likely causes determined were catastrophic failure of the solid rocket motor, collision with space debris, and loss of dynamic control of the spacecraft.

So CONTOUR was presumed lost. It was supposed to attempt fly-bys of comets Encke and Schwassmann-Wachmann-3, with a possible third flyby of comet d’Arrest.

In more successful space history, on this date in 1992 the Solar, Anomalous and Magnetospheric Particle Explorer (SAMPEX) mission launched from Vandenberg AFB on a Scout rocket. SAMPEX was designed to study cosmic rays, energetic particles emitted by the sun, and the magnetospheric particles for which it was named. The spacecraft was only expected to last about three years, but it continued to send back data until July 2004.

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Microgravity Science Lab Flies Again (Second Time's the Charm)

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Fifteen years ago today — July 1, 1997 — the Space Shuttle Columbia launched from the Kennedy Space Center carrying the Microgravity Science Laboratory (MSL).


(STS-94 launch. NASA image.)

Mission STS-94 was a “reflight” of the original MSL mission, STS-83, which launched three months earlier but ended early because of a fuel cell problem aboard Columbia. STS-94 marked the first time a shuttle mission was reflown with the same payload, same orbiter, and even the same crew. On this MSL mission — the 2nd time around — astronauts James D. Halsell, Susan L. Still, Janice E. Voss, Donald A. Thomas, Michael L. Gernhardt, Roger K. Crouch, and Gregory T. Linteris conducted a wide variety of experiments (“25 primary experiments, four glovebox investigations and four accelerometer studies”) during their 15 days in space.

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