Last of the Pre-Apollo Lunar Orbiters

By | |
Comments Off on Last of the Pre-Apollo Lunar Orbiters

Forty-five years ago today — August 1, 1967 — Lunar Orbiter 5 was launched by an Atlas Agena from Cape Canaveral.


(Lunar Orbiter 5. NASA image.)

As noted, Lunar Orbiter 5 was the last of the series, “designed to to take additional Apollo and Surveyor landing site photography and to take broad survey images of unphotographed parts of the Moon’s far side.”

The spacecraft acquired photographic data from August 6 to 18, 1967, and readout occurred until August 27, 1967. A total of 633 high resolution and 211 medium resolution frames at resolution down to 2 meters were acquired, bringing the cumulative photographic coverage by the 5 Lunar Orbiters to 99% of the Moon’s surface.

Mission Control commanded Lunar Orbiter 5 to de-orbit and hit the lunar surface five months after its photography mission was completed.

Facebooktwitterpinterestlinkedinmailby feather

Testing Tethers in Space History

By | |
Comments Off on Testing Tethers in Space History

Twenty years ago today — July 31, 1992 — the Space Shuttle Atlantis launched from the Kennedy Space Center on an international science mission.


(Tethered Satellite System. The tether itself is partly in shadow in this NASA image.)

STS-46 included U.S. astronauts Loren J. Shriver, Andrew M. Allen, Marsha S. Ivins, Jeffrey A. Hoffman and Franklin R. Chang-Diaz, Swiss astronaut Claude Nicollier, and Italian astronaut Franco Malerba.

Though technical problems delayed operations, the crew successfully deployed the European Space Agency’s European Retrievable Carrier (EURECA), an experiment-filled platform that stayed in orbit almost a year before being retrieved by the shuttle Endeavour. The Tethered Satellite System (TSS), a joint NASA/Italian Space Agency venture to test the behavior of tethers in space, did not deploy as planned; however, as a test, it proved that extending tethers in space is a more difficult and delicate task than anticipated.

Facebooktwitterpinterestlinkedinmailby feather

Riding the Earth's Wake, and Farewell to a Space Pioneer

By | |
Comments Off on Riding the Earth's Wake, and Farewell to a Space Pioneer

To start this space history item off in the usual fashion: 20 years ago today — July 24, 1992 — a Delta II launch vehicle carried the Geotail satellite to orbit from Cape Canaveral.

Geotail was built by Japan’s Institute of Space and Aeronautical Science as one of the International Solar Terrestrial Physics (ISTP) missions to study the interactions between the Earth and the Sun. Geotail primarily studied the magnetotail, a region formed by the solar wind interacting with the Earth’s magnetic field.

___

Unfortunately, we close this post by saying goodbye to a lady who made space history: physicist and astronaut Dr. Sally Ride, the first U.S. woman in space. Dr. Ride died yesterday of pancreatic cancer. Here’s a very nice profile from Spaceflight Now.


(Sally Ride. NASA image.)

Farewell, Sally Ride.

Facebooktwitterpinterestlinkedinmailby feather

Revolutionizing Civilian Remote Sensing: The Launch of Landsat 1

By | |
Comments Off on Revolutionizing Civilian Remote Sensing: The Launch of Landsat 1

Forty years ago today — July 23, 1972 — the Earth Resources Technology Satellite (ERTS) 1 launched from Vandenberg AFB atop a Delta rocket.

Renamed Landsat 1, the satellite was the first to demonstrate global remote sensing for “agricultural and forestry resources, geology and mineral resources, hydrology and water resources, geography, cartography, environmental pollution, oceanography and marine resources, and meteorological phenomena.”


(Landsat images of Mount St Helens. NASA image.)

According to this Landsat page, the choice of wavelengths for Landsat’s multispectral scanner (MSS) “was primarily based on forestry and geologic applications that had traditionally used Color IR photography.” At the time, multispectral imaging was “secondary and highly experimental,” according to this page, but scientists soon recognized the utility of the multispectral data.

The spacecraft operated until January 1978, five years longer than expected.

Facebooktwitterpinterestlinkedinmailby feather

For Want of a Hyphen, the Spacecraft Was Lost

By | |
Comments Off on For Want of a Hyphen, the Spacecraft Was Lost

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.

Facebooktwitterpinterestlinkedinmailby feather

What I Believe About What You Believe

By | |
Comments Off on What I Believe About What You Believe

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

Facebooktwitterpinterestlinkedinmailby feather

Lunar 'Explorer' Launched

By | |
Comments Off on Lunar 'Explorer' Launched

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.

Facebooktwitterpinterestlinkedinmailby feather

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

By | |
Comments Off on Yes, You Can Nominate for the Pegasus Awards … But Not For Long

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.

Facebooktwitterpinterestlinkedinmailby feather

A New Generation of Environmental Monitoring Capabilities

By | |
Comments Off on A New Generation of Environmental Monitoring Capabilities

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.

Facebooktwitterpinterestlinkedinmailby feather

An Ill-Fated Lunar Surveyor

By | |
Comments Off on An Ill-Fated Lunar Surveyor

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!

Facebooktwitterpinterestlinkedinmailby feather