#skylab

I saw this on Facebook and had to look it up. It really happened, albeit the details are different. From Homesteading Space: The Skylab Story:

"On the evening of MD-46, I finally played the trick that had been in work for over two month," said Garriott. "It even had the flight controllers puzzled for twenty-five years! My objective was to pretend that my wife, Helen, had come up to Skylab to bring us a hot meal, even though this was an obvious impossibility. Here is how the scheme worked. I recorded her voice on my small hand-held tape recorder before flight, pretending to have a brief conversation with a Capcom, with time gaps for his replies. The Capcom would be my only accomplice, but his role would be carefully disguised.

It was also necessary to have some recent event mentioned to validate the currency of the dialogue, so it would seem it could not have been recorded before fight. The short dialogue is printed below in its entirety. I knew that both Bob Crippen and Karl Henize were going to be Capcoms for Skylab, so they were brought into the planning, given the script and rehearsed on their timing. They kept the short script on a piece of paper in their billfolds, awaiting the right moment.

"For our flight in August-September, there would be many occasions of natural disasters involving forest fires or hurricanes, which would be widely known throughout the United States. So a few comments about one or the other were made on the tape. This led to four different scripts being recorded, one for each of the two Capcoms and one each for the two natural events. I would play the tape on the normal air-to-ground voice link with my wife's recorded voice and the Capcom would respond as if totally surprised by the female interloper."

Near the end of one period of voice contact Garriott said to the ground, "I'll have something for you on the next pass, Bob." Crippen replied, "Roger that, Owen." Then quietly and surreptitiously, he reviewed the brief script that had been in his pocket for all these weeks. Soon after coming into voice range, the ground heard this voice on the standard air-to-ground link:

Skylab (a female voice): "Gad, I don't see how the boys manage to get rid of the feedback berween these speakers.... Hello Houston, how are you reading me down there? (s sec. pause) Hello Houston, are you reading Skylab?"

Capcom: "Skylab, this is Houston. We heard you alright, but had difficulty recognizing your voice. Who do we have on the line up there?"

Skylab: "Hello Houston. Roger. Well I haven't talked with you for a while. Isn't that you down there, Bob? This is Helen, here in Skylab. The boys hadn't had a good home cooked meal in so long, I thought I'd bring one up. Over"

Capcom: "Roger, Skylab. Someone's gotta be pulling my leg, Helen. Where are you?"

Skylab: "Right here in Skylab, Bob. Just a few orbits ago we were looking down on those forest fires in California. The smoke sure covers a lot of territory, and, oh boy, the sunrises are just beautiful! Oh oh..... See you later, Bob. I hear the boys coming up here and I'm not supposed to be on the radio."

"Then quiet returned to the voice link, but we were told later, Bob Crippen had lots of questions coming his way in the Control Center," Garriott said. "What was going on? Where was this voice coming from? Bob must have been a very good actor, because he claimed complete ignorance and innocence of how it happened. Everyone heard it coming down on the air-to-ground loop. The whole two-way conversation sounded like a perfectly normal dialogue. No breaks or gaps, and they all heard Bob respond in real time. Could I have recorded Helen's voice on a 'family conversation' from our home? Yes, but there was no recent one. How would she have known about the fires, or who was to be on Capcom duty and how could she respond to Bob's comments in real time, as everyone could hear?

"No one ever worked out how this was accomplished. Finally, at our twenty-fifth reunion celebration in Houston in 1998, and with many of the flight directors and controllers present and still with no clue as to how it was done, I described it all as above. My prejudiced opinion is that this was the best 'gotcha' ever perpetrated on our friendly flight controllers!"

Crippen recalled: "That was kind of a fun trick. There was head rubbing.

SCAN AND REMASTERED by Dan Beaumont: link

"Artist's rendering shows how Command Service Module (CSM) will dock with the Orbiting Workshop (OWS) during the Skylab mission. Assisting in the docking is the VHF Ranging System designed and built by RCA Government Communications Systems, Camdem, N.J. The system provides the CMS pilot with the range between the two spacecraft. Ranging is performed by sending radio tones from the CSM to the workshop, which retransmits them to the CSM. The range is determined by measuring the time between the transmission of the tones and receipt of the OWS retransmitted."

Date: May 12, 1973

Today's WBW topic is a brave little swimmer that has boldly gone where no fish has gone before. Yes this tiny champion is the first fish to go to space. But you don't need to look to the skies to find these fish fascinating, there's plenty to appreciate even on Earth.

(Image: a mummichog next to someone's fingers for scale. It is about the size of a finger/ It is a small, green fish with a long body, founded fins, and silver specks that form vertical bars toward the rear of the body. End ID)

Mummichogs (Fundulus heteroclitus) are killifish that typically reach 7.5 to 9 cm (3 to 3.5 cm) but can grow up to a whopping 15 cm (6 in). There are two subspecies: the northern and southern mummichogs. The difference between them is very subtle and mostly appears in their eggs, which I'll cover in the reproduction section. Unlike most fish, mummichogs do not have lateral lines. The lateral line is a series of sensory pores that run down the body of most fish and some amphibians. The pores detect changes in water pressure, allowing the fish to sense the movement of water around them. While mummichogs have lost the ancestral lateral line, they still have sensory pores on the face. Mummichogs have a limited ability to change color, which they used for camouflage and possibly communication. Usually, they are olive green to brown, with lighter undersides. Sometimes they will display thin, silvery, vertical bars on the sides. Males change color during mating season, described in the reproduction section. Males also have larger dorsal and anal fins than females.

(Image: a male (top) and female (bottom) mummichog. The male has a shorter, more robust body with a more blunt head. End ID)

While most killifish are freshwater species, mummichogs are oceanic. They dwell in coastal areas of the North American Atlantic coast from northern Florida to Canada. Habitats include intertidal zones, estuaries, salt marshes, and up rivers. Mummichogs can tolerate a very wide range of salinity, from freshwater to almost three times the salinity of regular ocean water. This allows them to swim up rivers, though they usually stay below the head of tide (the point where a river is affected by the tides) and there are a few lake-bound introduced populations. They prefer muddy bottoms with seagrass or plants to provide shelter, but can tolerate other conditions. Mummichogs are shoaling fish that live in shoals up to a few hundred strong. Shoals differ from schools require all the fish involved to be moving together whereas shoals are any group of fish that stick together for social reasons. The shoaling behavior actually helped inspire their name. Mummichog comes from a Narraganset word that means "moves in crowds". Shoaling helps the group find food and avoid predators. A lone mummichog is more likely to be targeted by a predator than one of dozens in a shoal. Shoals also mean more eyes looking out for danger. Mummichogs are opportunistic omnivores that eat algae, small invertebrates, seagrass, fish eggs (including those of their own species), and plankton. During winter, those living on the northern part of their range will bury themselves in mud and hibernate until spring.

(Image: a group of thee mummichogs, two of which are males in mating season coloration. They have more pronounced vertical bars and orange underbellies. End ID)

Life in the intertidal zone is one of extremes and mummichogs have adapted well to extreme conditions. As mentioned above, they can survive in a wide range of salinities. They can also survive a wide range of temperature, from 6 to 35°C (59-86°F) including relatively rapid temperature changes. They survive these temperature changes by speeding up or slowing down their metabolic functions. They can also survive low-oxygen environments and can even survive for a few hours out of water as long as they stay wet. These adaptations allow them to survive in tidepools during low tide. Tidepools are harsh environments. Once a pool is isolated from the ocean, exposure to the sun can heat up the water and increase the salinity through evaporation. Oxygen is used up by all the animals in the pool and that's in addition to the issue of warmer water holding less oxygen that cold water. Mummichogs are very well adapted to survival in these hostile environments. Their ability to survive on land for a while can help in the case that a tidepool becomes too harsh even for them. A mummichog lying on its side can contract its muscles to jump many times its body length. This could help one find a more suitable tidepool or make its way back to the ocean. Mummichogs are also highly resistant to many types of environmental toxins. They can quickly develop resistance to introduced pollutants by apparently modifying their genes. One study found that a population living in a bay polluted with polychlorinated biphenyls and another living in a river polluted by creosote had about 20% of their genes modified when compared to populations living in clean water.

(Image: a mummichog held in someone's hand. This one is very dark with prominent silver bars and a white belly. End ID)

Mummichogs reproduce from spring to fall during high tide. They prefer to spawn during spring tides: especially high tides following new or full moons. They prefer to mate at night, but will in the day if necessary. During mating season, males will become more brightly colored, gaining blueish sides, silvery vertical bars along the sides, and orange bellies. These colors apparently attract mates. Females will signal they are ready to mate by turning on their sides and flicking their tails. Males will pursue females and a pair may swim together for a while before mating. When the time comes, the male will maneuver the female against a rock or plant and grab onto her using his dorsal and anal fins. They then release sperm and eggs together. The eggs of the northern subspecies have sticky filaments on them while the southern subspecies' eggs don't. They will target sheltered places at very high tide to lay their eggs, such as plants, seaweed, rocks, and shells, and the northern subspecies will also lay right onto sand or mud. The eggs will be exposed to the air once the tide goes down and will continue to develop as long as the air is wet enough to keep them from drying out. When the water returns during next month's spring tide, the eggs will hatch. The juveniles spend their first few weeks in the intertidal zone before growing large enough to move to deeper water and join shoals. They become sexually mature around age 2 and can live up to 4 years. Mummichogs can hybridize with the closely related banded killifish Fundulus diaphanus.

(Video: a female mummichog spawning. There are multiple mummichogs swimming in shallow water over a shandy bottom. A female is displaying over a bivalve shell. She repeatedly turns her body sideways over the shell and wriggles. Eventually, a male comes to mate with her. The act of mating is extremely brief and easy to miss, but both fish leave the shell afterwards. End ID)

Mummichogs are classified as least concern by the IUCN, meaning they are not at risk of extinction. They are abundant withing their habitats and capable of living in some of the most heavily polluted streams in their territory. There are rives out there so polluted that mummichogs are the only fish species that live in them. Mummichogs have been introduced to lakes, streams, and drainage ditches outside of their native range to help control mosquito populations. Mummichogs are highly effective predators of mosquito larvae. Aside from a small live bait market, there isn't a commercial interest in mummichogs. Mummichogs are heavily used in science as model organisms for stress and poison resistance due to their small size, tolerance for bad conditions, and ability to thrive in captivity. Their eggs are translucent enough to allow for microscope viewing of the process of development through the larval stage, making them useful for developmental studies. The embryos are also durable enough to be manipulated by lab equipment and survive. Their usefulness in labs contributed to mummichogs being the first fish in space. In 1973, a group of mummichogs and eggs were take aboard the Skylab space station and observed. The adults took several days to adjust to swimming in microgravity, they initially pitched forward too much and swam in circles, but they eventually figured out how to swim normally. Hatchlings on the space station were able to swim normally from birth. Since then, mummichogs have been taken on a few more space missions.

2006 April 29

Skylab Over Earth

Credit: Skylab, NASA

Explanation: Skylab was an orbiting laboratory launched by a Saturn V rocket in May 1973. Skylab, pictured above, was visited three times by NASA astronauts who sometimes stayed as long as two and a half months. Many scientific tests were performed on Skylab, including astronomical observations in ultraviolet and X-ray light. Some of these observations yielded valuable information about Comet Kohoutek, our Sun and about the mysterious X-ray background - radiation that comes from all over the sky. Skylab fell back to earth on 11 July 1979.

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (USRA)

NASA Official: Jay Norris.

A service of: EUD at NASA / GSFC