Deborah's Journal

This beautiful spiral galaxy, which goes by the utterly inadequate name of NGC 3370, may be what our own Milky Way Galaxy looks like from the outside. It's about 100 million light-years away, in the direction of constellation Leo. This image is from the Hubble Space Telescope's Advanced Camera for Surveys, and is good enough so we can study individual stars. It contains a well-studied supernova as well as Cepheids, pulsating stars, that help us to measure the distance to NGC 3370. Combining this distance with observations of supernovas at even greater distances gives us information about the size and expansion rate of the universe.

ore strange and wonderful theoretical stuff" As we look backwards in time, the universe gets denser and hotter; we know this from the absorption lines in the background radiation, and it fits with our current theory. The densities of galaxies have also evolved as expected.

In the first seconds after the Big Bang, radiation dominated, then matter dominated with formation of galaxies.

Electrons and positrons collided, annihilated one another, and created gamma ray photons. For a brief time, there existed an equilibrium between matter, anti-matter, and radiation. However, there was an excess of 1 matter particle out of every billion particles, so the system was no longer in equilibrium, although this process is not yet well understood.

During the first few minutes, the universe expanded and cooled; protons and neutrons formed a few helium nuclei, the rest of the protons remained as hydrogen nuclei. Free neutrons have a half-life of 15 minutes, so if they get locked up in helium, they're are out of circulation; others wound up decaying to produce more hydrogen. Some of these processes extended beyond first few minutes, but helium is a limiting factor, tying up neutrons.

The radiation dominated era produced hot plasma (ionized gas) and a period of expansion and cooling, but no new synthesis of elements. Photons were incessantly scattered by free electrons, in equilibrium with matter.

Then followed an era of recombination. Protons and electrons recombined to form atoms, in a transition to the matter-dominant era. Temperature fell to a few thousand K, like the surface of a star. Gas was no longer ionized plasma, but neutral hydrogen, which does not react so readily to photons, so the universe became "transparent" to photons. Radiation could penetrate billions of light years and be detected by us. This is where microwave background radiation comes from.

Reionization. After less than 1 billion years, the first stars formed; ultraviolet radiation from the first stars and quasars (emit ionizing radiation) re-ionized the gas in the early universe. Bubbles of ionized gas overlapped, and the universe became opaque again.

Cosmological principle assume: Homogeneity, that the local universe has same physical properties throughout the larger universe, each region has same physical properties (mass density, expansion rate, visible vs. dark matter). Isotropy (no preferred direction); on largest scale, local universe looks the same in any direction. Universality; the laws of physics are the same everywhere in the universe (size scale > 100 million parsecs.)

Space itself seems to posses a "dark energy" or anti-gravity that acts to expand space, an intrinsic energy associated with space/vacuum. We have no clue what this is, but it seems to be the most important energy constituent of the universe today.

Until 6 billion years ago, the gravitational energy of matter was stronger than the acceleration forces, but then dark energy began to dominate energy density of universe. We see an anti-gravity effect that pushes things apart faster and faster. Today, the acceleration due to dark energy dominates, creating an exponential expansion. If the energy density remains constant, we get a future "the big empty." Galaxies will move away faster than the speed of light, so their light will never reach us. Within the Milky Way, however, systems will be held together by gravity, but we won't be able to see beyond our galaxy.

Contraception would be very important in space, because of limited medical resources for pregnancy and potentially hazardous/deadly effects on embryo (such as increased radiation exposures). No method other than sterilization is 100% effective; the effectiveness of oral contraceptive in microgravity is not known. In microgravity, sperm may linger in vaginal tract, as their movement is not dependent upon gravity: transport by muscle contractions, ciliary activity, and the motility of sperm. On the other hand, microgravity and spaceflight by themselves may have contraceptive effects. Menstrual dysfunction is likely due to disturbance in circadian rhythms, intensive exercise, stress. Disturbance of the hypothalamic-pituitary-ovarian axis lead to lack of ovulation or excessive menstrual bleeding. This may include retrograde menstruation, producing endometriosis and infertility. Male fertility: fall in testosterone level and sperm motility, exposure to toxins used in life-support and propellants could reduce sperm counts.

Higher radiation levels can affect both male and female fertility. Sperm cells are the most radiosensitive in human body, resulting in reduced fertility or genetic abnormalities. Sperm cells produced on a 74-day cycle, so levels return to normal after low radiation exposures. Radiation doses needed to destroy all sperm cells are usually fatal. Ovaries lie 5-7 cm below the skin, so some slight shielding. Oocytes more radio-resistant to genetic defects than are sperm cells, but are not replaced if damaged. In women, a radiation exposure of LD50 (enough to produce 50% fatality rate) results in sterilization (destruction of all oocytes and end to estrogen production) but effects of radiation are cumulative. Radiation can cause endometriosis.

Conception has occurred in female rats in space, but the embryos were reabsorbed. Male rats mated after flight produced offspring with higher rates developmental abnormalities, including growth retardation. But fish produced viable offspring. The opverall effects of space environment on human fertility unknown.

Pregnancy in space. Must consider pre-existing pregnancy or one originating in space. Adverse effects (microgravity, radiation) are expected to be greatest during the early stages, particularly genetic damage to to the embryo. Morning sickness would be more difficult to manage, if combined with Space Adaptation Syndrome. This might lead to "hyperemesis gravidarum" with dehydration and liver damage. A woman might experience all the complications of a pregnancy on Earth, combined with limited medical care, which could lead to serious injury or death; conditions like urinary tract infections and gestational diabetes would be more difficult to treat. Example: pre-eclampsia - hypertension, protein in urine, headache, visual disturbances, can worsen into eclampsia, with potentially fatal seizures and coma. Hemorrhagic complications: abruptio placentae - limited blood supplies for transfusion, hypovolemia and mild anemia could worsen effects; fetus more sensitive to maternal blood loss - anoxic encephalopathy.

Other complications: ectopic pregnancy, pre-term labor, rupture of the amniotic sac during acceleration/deceleration of launch and re-entry, exposure to toxins.

Might there be benefits to microgravity? It could reduce incidence of varicose veins, edema, back pain and difficulty in moving in later pregnancy, lightheadedness due to compression of the inferior vena cava when supine.

Childbirth in microgravity would require securing the woman and her assistants, maintain sterility, and containing fluids (such as amniotic fluid); spinal anesthesia is partly dependent upon gravity; cesarean section would require higher level of sterility, trained personnel, and proper equipment, than is currently available in space.

Decompression sickness: nitrogen bubbles in the circulatory system of a fetus can pass from veins into arteries through foramen ovale and ductus arteriosus (fetal bypass), would be much more dangerous if they occurred in arterial side and would impair blood supply to critical organs, such as brain and heart. Other risks to fetus: radiation danger is extreme (maximum allowed adult dose for 9 months is 0.5 rem, in LEO - Low Earth Orbit - annual exposure is 14-21 rem). If in deep space or if there is a solar particle event, the resulting exposure can be very high. If this occurs in the first 2 weeks of pregnancy, it would result in the destruction of the zygote. Developmental abnormalities would occur from exposure during 8-25 weeks gestation.

The probability of conception with effective contraception is low. However, the risk to the mother and developing embryo/fetus is very high. Risks are increased with time in space and distance from terrestrial medical care. Problems may be ultimately surmountable but for now, the risk/benefit is very unfavorable.

Kids in space: children are more susceptible to radiation than are adults, and the risks of microgravity are also worse. Bones/muscles still developing, so microgravity is likely to result in growth retardation, especially the long bones in thighs and legs. Also possible are delayed closure of the fontanels, short stature, abnormal development of vertebrae, potentially resulting in nerve compressions syndromes. Epiphyses may close early. Adults need vigorous exercise to maintain 85% muscle/bone mass, but kids can't use adult-sized equipment and may be uncooperative, might result in levels well below 85%.
They may experience difficulty learning to walk and balance, and problems with neurovestibular reflexes. Effects on overall neurological development are unknown.

Long-term radiation exposure increases lifetime risk of cancer. Immature immune system may increase risk of infection. Just having small children in spacecraft is recipe for disaster.

Currently, sex in space is both risky and potentially deadly. But we must find ways to reduce these risks for successful long-term flight and eventual colonization of space.

Sex with aliens requires a bare minimum of "complementary" anatomy. Also faith that alien sexual practices do not lead to unexpected consequences, confusion of expectations if species has more than 2 genders, black-widow-spider syndrome. Offspring very unlikely even with genetic engineering. Alien physiology almost certainly radically different from terrestrial, evolved under different condition, different DNA, proteins, amino acids, cells, etc.

To begin with, unless we're talking about masturbation, we need access to a partner in order to have sex. Early ventures into space were not conducive to sexual activity. The first human space flights were one man flights. When, in 1963, the first woman cosmonaut went into space, she flew with another man, but she was in one-person capsule and he was in another, and the flight did not include any docking maneuvers. Through the 1970s, crews contained only men until Salyut 7, which was a mixed crew (1982). 1983 Sally Ride, since then mixed crews common, and in 1992, a married couple. Did any of these flights include sex in space? Who knows? There's no official confirmation. Is it possible? Theoretically yes, but difficult: microgravity, effects on physiology, radiation, psychological effects. Read on...

Why is space a terrible place for sex? Sex desire is likely to be curbed by the physiological effects of space flight, such as space adaptation syndrome (onset within 2 hours, and persisting up to a week, experienced by 2/3 trained crew and 85% of those less well trained; includes headache, nasal congestion, dizziness, nausea, vomiting without warning); anxiety about the dangers of space, busy work schedule, lack of privacy. Male rats experience a decrease in testosterone levels (to less than 20% normal) and this is likely true also for human; anemia, fluid loss, reduced autonomic nervous system function, especially sympathetic tone (needed for climax in both men and women); reduction bone and muscle mass; sex in space may require significantly more energy and higher risk of fractures.

Normal sexual intercourse uses 2-3 METs; at climax increased to 4 METs (about the energy of walking 3-4 mph). Heart rate rises to 130 pbm, blood pressure to 170-180 systolic. In a stressful environment and an unfamiliar partner, the expenditure can be much higher (5-6 METs). The deconditioning, fluid shifts, and loss of autonomic tone due to microgravity may further increase energy expenditure, heart rate and blood pressure during intercourse to potentially dangerous levels. Normally, risk of myocardial infarction or death is 1-2 per million; we don't know risk in space environment.

Astronauts are screened for STDs, but this might not be true for space tourists. Microgravity results in a mild reduction in immune function, thus increasing the risk of contracting an STD.

Planets are teeny specks in the middle of nothing, separated by vast distances. 8 major planets with nearly circular orbits; Pluto and Eris are smaller and have more elliptical orbits; Pluto-like objects (many!) Eris is larger than Pluto! (Kuiper belt, objects rocky and icy like comets, 1/2 dozen we know about so far.)

Sun comprises 99.9% of solar system's mass, mostly H/He gas; converts 4 million tons of mass into energy each second.

Mercury - metal and rock, large iron core; desolate, cratered with long, tall steep cliffs, very hot/cold 425oC to -170oC Why iron core: During planetary accretion, lighter elements blown off, only heavier elements left. Outer planets - ices solid, grow bigger and more quickly than inner planets. Jupiter orbit = "frost line" for volatile gases being ice (but we are having to re-think the frost line in light of "hot Jupiters" that orbit very close to their stars.)
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Today was Travel Day, the process of gathering warm bodies from the many corners of the land. Dave made me waffles, sweet man. We trundled off to San Jose Airport, where I discovered that my flight was delayed, albeit not by much. Mike Brotherton says that one year, transport was such a mess, people didn't all arrive until 10 pm and then the dorm keys didn't work. We, however, all made it in at a civilized hour, trekked by van from Denver to Laramie, checked in, and walked up the block to a sort of sports bar/brewput/burger joint named, either appropriately or inappropriately, "The Library." (As in, Mom, I was at the Library until 12 am!)

On the way, I saw unbelievably flat land with unbelievably straight roads. But also very beautiful mountains and hills and lots of green... and pronghorn antelope, browsing along the freeway. Gorgeous caramel and cream beasties. To a Californian, very exotic. Also some birds that Stan Schmidt, riding in my van, said were ravens. Also some camels from a sort of wildlife station place, looking very out of place amid all that green.

We also had a little thunder and a little rain, mostly in Denver. These are not so exotic, although the locals seem to take them for granted more than I do.

Class begins at 10 am tomorrow, looking at scales of the universe. Our instructors are Mike Brotherton and Jim Verley, plus Stan Schmidt and Jerry Oltion. We are in a dorm at one end of the campus, and classes are in Classroom Building at the other end. There appear to be no campus maps of the sort one may carry around. For me, who is the most directionally-challenged person I know, this presents interesting possibilities.

Strictly personal: I'm in a dither -- it's been so long since I've spent a whole day in class -- my mind is telling me I ought to have been reviewing my college physics -- and reading every basic astronomy book I can find --and now it's too late -- omg -- I'm going to be such a slow and stupid person. The only thing I can do is laugh. If I've learned anything in my more-than-a-few decades, it's that we all learn at different rates and in different ways. Ask me a certain type of question and my mind is an instant blank, even though I can recite the answer in my sleep (maybe I should try that as a tactic!) Or, when faced with some utterly intimidating situation, exactly the right words fly out of my mouth. I figure, what the heck, if I'm feeling so insecure and I have a fabulous time, maybe someone else might not let that stop them from applying next year!

The schedule arrived today via email and I'm so geekily stoked, all my performance anxiety has disappeared.
Monday: welcome and stuff, Scales of the Universe; A Scale Solar System; Seasons, Lunar Phases, Misconceptions; Amateur Astronomy; Small Telescope Night (omg squee, as my kids would say)

Tuesday: The EM Spectrum, Light, Instruments, Telescopes; Infrared Astronomy and Dust; Kirschoff's Laws and Spectra; Hazards and Healthcare in Space.

Wednesday: Gravity, Newton, Kepler, Orbits; Planets, Solar & Extrasolar; All About Stars; Astronomical Worldbuilding, Biology, Culture; WIRO (Wyoming Infrared Observatory) visit

Thursday: (morning hike, undoubtedly to clear our brains!); Supernovas, White Dwarfs, Neutron Stars, Black Holes; Science Education and SF.

Friday: Galaxies & Dark Matter; Sex in Space; How to Move the Earth; Computing in Astronomy.

Saturday: What Not To Do (with Stan Schmidt); Cosmology; Discussion and goodbyes.

I have been advised that my brains will be oozing out my ears by the end of the week. Thank goodness, we get to take home a textbook!

Oh, and thunderstorms are predicted for the first part of the week, so the observatory visits may get shuffled around.