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But since the reactor's energy has to be divided up to service more propellant per second, each kilogram of propellant gets less energy, so the exhaust velocity and specific impulse goes down. Could you please help? Once arrived at a mining site, the tungsten elements, together with wall of ceramic lego-blocks produced in-situ from regolith by magma electrolysis are used to build an electric furnace. I just adopted a 7 year old Cockatiel 3 days ago and he is very aggressive and flys out at me when I open the cage any suggestions on taming. Unable to see her body, she swore she was being disfigured further.
The first three requirements are called "consumables", since they are gradually used up by the crew. Each of those three can be controlled by either an "open" system or a "closed" system.
Open systems are ones where a supply of the consumable in question is lugged along as cargo, enough to last the for the planned duration of the mission. It is renewed by "resupply", by obtaining new supply from a resupply spacecraft, a base, or an orbital supply depot.
Things can get ugly if the mission duration becomes unexpectedly prolonged, for instance by a meteor scragging the spacecraft's engine. Closed systems are ones where the supply of the consumable in question are renewed by some kind of closed ecological life support system. Generally this takes the form of some sort of plants, who use sunlight to turn astronaut sewage and exhaled carbon dioxide into food plants and oxygen. Note that requirements for consumables can be drastically reduced if some of the crew is placed into suspended animation.
If you want more data on life support than you know what to do with, try reading this NASA document. As a very rough rule of thumb: Of course this can be reduced a bit with hydroponics and a closed ecological system. This also makes an attractive option out of freezing one's passengers in cryogenic suspended animation. Eric Rozier has an on-line calculator that will assist with calculating consumables.
Many of the settlers of Talentar, who would later become dirt farmers and ecopoetic line techs, were drawn from rural areas of Eliéra, seeing an opportunity to apply their sophisticated knowledge of modern agriculture and silviculture to the problems of making this new world blossom.
It is from these settlers that a local variation in the rights and customs of hospitality has become ubiquitous. Many of the foresters and line techs of the Delzhía Terra region in particular were drawn from the wooded upland valleys of the Vintiver region. A traveler by foot or rover can stop at any of the small domes or prefabs dotting the dusty plains, signal at the service hatch, and receive a charge for their powercells, a fresh oxygen tank for an expended one, and a packed handmeal of the local produce — an invaluable service for traveling light, or in a pinch.
According to NASA, each astronaut consumes approximately 0. They breath out 0. At that pressure, one person day of oxygen takes up about 0. Stored as liquid oxygen, 0. This requires extra mass for the cryogenic equipment to keep the oxygen liquid, but the volume savings are impressive. So as far as pure oxygen goes, you take 0. Repeat with the volume figure for the total oxygen volume requirement.
However, this is just pure oxygen. This is insanely dangerous to use as the ship's atmosphere, the accident that killed the Apollo 1 crew proved that. In practice one uses a "breathing mix" of oxygen and another gas. Generally the other gas is nitrogen. The technical term is " nitrox ". The shuttle space suits use 4. Setting up the optimal breathable atmosphere is complicated.
The amount of oxygen must be kept under strict limits or oxygen toxicity will harm the crew. The Bono Mars Glider uses a heliox atmosphere, but I cannot figure out why. For example, to avoid nitrogen narcosis, station air supplies are mixtures of oxygen and helium rather than oxygen and nitrogen. This means that regular station residents speak with the squeaky cartoonlike voices that result when human larynxes vibrate in a helium environment.
Those who live in such stations say they quickly become accustomed to the phenomenon. Psychological tests prove otherwise. Extended exposure to high-pitched helium voices causes severe subconscious stress, leading to a variety of mental disorders—from general anxiety and mood swings to clinical depression and outbursts of rage.
The reason is simple: Homo sapiens evolved as social animals, and they have a deep-seated need to hear voices that are recognizably human. These people are not researchers: Wherever these people go, they ease tension and make it possible for others to concentrate on their work.
There are two methods of cracking CO 2 into C and O 2: Low energy requires huge amounts of biomass in plants. Data from Biosphere II indicate roughly seven tons of plant life per person per day, with a need for roughly 4 days for a complete plant aspiration cycle, so call it 25 to 30 tons of plant per crewman. With an average density of 0. High energy methods take up much less space, but as the name implies requires inconveniently large amounts of energy.
It also results in lots of messy by-products and waste heat. Practically, it is easier to flush the CO 2 instead of cracking it, and instead bringing along an extra supply of water to crack for oxygen. Water is universally useful with a multitude of handy applications, and takes less energy to crack than CO 2. For future Mars missions, it has been suggested that the life support system should utilize the Sabatier Reaction.
This takes in CO 2 and hydrogen, and produces water and methane. The water can split by electrolysis into oxygen and hydrogen, with the oxygen used for breathing and the hydrogen used for another batch of CO 2. Unfortunately the methane accumulates, and its production eventually uses up all the hydrogen.
For emergency use, it would be wise to pack away a few Oxygen Candles. These are composed of a compound of sodium chlorate and iron. Molecular Product's Chlorate Candle 33 masses It is not enough to supply oxygen to breath, you also have to remove the carbon dixoide. Bad things happen if the CO 2 levels rise too high.
NASA says that each astronaut exhales 0. In the Apollo program spacecraft, NASA used lithium hydroxide based scrubbers, which fill up and have to be replaced. Oxygen tanks have enough to last for the duration of the mission, and is gradually used up.
Actually it is converted into carbon dioxide and is absorbed into the scrubbers, where it cannot be used any more. You may remember all the excitement during the Apollo 13 disaster, when NASA learned the life-threatening dangers of non-standardization. The crew had to use the Command Modules' scrubber cartridges to replace the ones in the Lunar module. They had to rig an adaptor out of duct tape and whatever else was on-board.
Metal-oxide scrubbers remove the CO 2 as before. But when they get full, instead of being replaced, they can have the CO 2 flushed out by running hot air through it for ten hours.
Then they can be reused. In the following specifications, the mass kg , volume m 3 , and electrical power requirements W is for equipment sized to handle a six person crew. First the stale air is pumped through a 4-Bed Molecular Sieve It initially removes the water from the air and sends it to be added to the life support water supply , then it removes the carbon dioxide. The carbon dioxide and some hydrogen from a source to be explained shortly are fed into a Sabatier Reactor 26 kg, 0.
They react producing methane and water: The methane is vented into space. The water is fed into an electrolyser to be split into hydrogen and oxygen. The hydrogen is sent back to the Sabatier Reactor to take care of the next batch of carbon dioxide. The oxygen is added to the breathing mix and released into the habitat module's atmosphere. The TransHab starts out with a tank of high pressure oxygen The oxygen tank has three days worth of breathing for six crew, enough to give the Sabatier Reactor time to get started.
The nitrogen tank has enough to establish the proper ratio for the breathing mix, and some extra to compensate for any atmosphere leaking into space. Jensen; someday you'll come a cropper with a planet that is new to you! As I was saying, we got this rust infection about ten days out. I didn't have any more farm than an Eskimo.
I cleaned the place out, sterilized, and reseeded. The infection was all through the ship and I couldn't chase it down. We finished that trip on preserved foods and short rations and I wasn't allowed to eat at the table the rest of the trip.
I exhausted the air from an empty compartment, suited up, and drilled a couple of holes to the outside. Then I did a piping job to carry foul air out of the dark side of the ship in a fractional still arrangement — freeze out the water first, then freeze out the carbon dioxide. Pesky thing was always freezing up solid and forcing me to tinker with it. But it worked well enough to get us home.
Bart and Dan went off to do that, and Jim followed behind them. But from their faces, he could tell that their hopes weren't too high. Obviously, most of the oxygen had been put into the new extension, since there was more room there for the big containers of liquid oxygen. They had been in the shadow, below the main part of the hull, where they could stay liquid; but the heat of the fire had bent and twisted them, and some had even exploded violently.
Gauge will tell you what per cent has been used. It was a lot less than they would have liked. And we don't have chemicals to soak up the carbon dioxide they breathe out for even that long.
In a vague way, Jim still felt responsible for the trouble. He should have checked on his assistant. He'd been beating his head, trying to remember what he'd learned in high school about the behavior of the gas. His father had always maintained that a man could accomplish almost anything by reducing things down to the basic characteristics, and then finding out what was done in other fields.
He realized his mistake before the others swung on him. What are the basic characteristics of carbon dioxide? The young man who'd studied chemistry piped up again. Animals breathe it out, and plants breathe it in, releasing the oxygen again.
It freezes directly to a solid, without any real liquid state, and is then known as dry ice. What about the cold side—does it get cold enough to freeze it out? Dan, any way to get a gastight pan.
We could blow it through there slowly enough—trial and error should tell us how slowly. In most space program, they use two breathing mixes for the atmosphere inside the habitat modules and space suits. Low Pressure pure oxygen at High pressure breathing mix is pretty close to ordinary Terran air at sea level. The important thing to note is that for a low pressure breathing mix, the crew will die of anoxia if the atmospheric pressure falls below 5.
For a high pressure breathing mix, anoxia lies below The basic limit is anoxia ocurrs when the Partial Pressure of oxygen drops below 5. Anoxia will hit the crew when the atmospheric pressure drops to what pressure? Low pressure is attractive; since it uses less mass and the atmosphere will escape more slowly through a meteor hole. Unfortunately the required higher oxygen level make living in such an environment as hazardous as chain-smoking inside a napalm factory.
NASA found that out the hard way in the Apollo 1 tragedy. Since then NASA always uses high pressure, they use low pressure in space suits only because they cannot avoid it. This does raise a new problem. There is a chance that the high-oxygen atmosphere will allow a meteor to ignite a fire inside the suit. There isn't a lot of research on this, but NASA seems to think that the main hazard is a fire enlarging the diameter of the breach, not an astronaut-shaped ball of flame.
There are other problems as well, the impossibility of air-cooling electronic components and the risk of long-term health problems being two. A more annoying than serious problem with low pressure atmospheres is the fact that they preclude hot beverages and soups. It is impossible to heat water to a temperature higher than the local boiling point.
And the lower the pressure, the lower the boiling point. You may have seen references to this in the directions on certain packaged foods, the "high altitude" directions. The temperature can be increased if one uses a pressure cooker, but safety inspectors might ask if it is worth having a potentially explosive device onboard a spacecraft just so you can have hot coffee.
Decompression sickness also known as DCS, divers' disease, the bends or caisson disease is one of the more hideous dangers of living in space. It occurs when a person has been breathing an atmosphere containing inert gases generally nitrogen or helium and they move into an environment with lower pressure. This is commonly when they put on a soft space suit or the room suffers an explosive decompression.
It has all sorts of nasty effects, ranging from joint pain and rashes to paralysis and death. The large joints can suffer deep pain from mild to excruciating.
The brain can have sudden mood or behavior changes, confusion, memory loss, hallucinations, seizures, and unconsciousness. The legs can become paralyzed. Headache, fatigue, malaise, loss of balance, vertigo, dizziness, nausea, vomiting, hearing loss, shortness of breath, and urinary or fecal incontinence: Why does it happen? Well, imagine a can of your favorite carbonated soda beverage. Shake it up, and nothing happens. But when you open it, the soda explodes into foam and sprays everywhere.
When you open the container of shaken soda, you lower the pressure on the soda fluid. This allows all the dissolved carbon dioxide in the soda to un-dissolve, creating zillions of carbon dioxide bubbles, forming a foam. Now imagine that the carbon dioxide is nitrogen, the drink is the poor astronaut's blood in their circulatory system, and the foam is the deadly arterial gas embolisms. That's what causes the bends.
Please note that sometimes the bends can occur if one moves from one habitat to another that has the same pressure, but a different ratio of breathing mix the technical term is "Isobaric counterdiffusion". Spacecraft of different nations or models could use different breathing mixes, beware. In fact, rival astromilitaries might deliberately utilize odd-ball breathing mixes, to make life difficult for enemy boarding parties invading their ships.
The bends can be prevented by slow decompression , and by prebreathing. Or by breathing an atmosphere containing no inert gases. Slow decompression works great for deep-sea divers but NASA does not favor it for space flight. An atmosphere with no inert gases pure oxygen is an insane fire risk. NASA does not allow a pure oxygen atmosphere in spacecraft and space stations, but will allow it in space suit in a desperate attempt to lower the suit pressure to the point where the astronaut can move their limbs instead of being trapped into a posture like a star-fish.
So NASA astronauts do a lot of prebreathing. This flushes nitrogen out of the blood stream. NASA uses Terra-normal pressure The astronaut s enter the airlock, and the airlock pressure is reduced to They breath pure oxygen through masks for 60 minutes because the air in the airlock contains nitrogen.
They then put on their space suits and do an EMU purge i. The air inside their suits is now also pure oxygen. The airlock pressure is then brought back up to the normal They then do minutes of in-suit prebreath. Of those minutes, 50 of them are light-exercise minutes and 50 of them are resting minutes.
Thus "Slow Motion Hokey Pokey". Now they are ready to open the airlock and step into space. The innovation was the 50 minutes of exercise. Without it, the entire protocol takes twelve hours instead of one hour and fifty minutes. If the habitat module's pressure was 12 psi an astronaut could use an 8 psi space suit with no prebreathing required a pity such suits are currently beyond the state of the art , and for a 4.
In case of emergency, when there is no time for prebreathing, NASA helpfully directs the astronauts to gulp aspirin, so they can work in spite of the agonizing pain. Please note that most of the problem is due to the fact that soft space suits have a lower atmospheric pressure than the habitat module. So this can be avoided by using a hard space suit or space pod. All of the atmospheric controls will be on the life support deck.
On a related note, forced ventilation in the spacecraft's lifesystem is not optional. In free fall, the warm exhaled carbon dioxide will not rise away from your face. It will just collect in a cloud around your head until you pass out or suffocate.
In the image above the blue dome shaped flame is an actual candle burning in free fall. And in Clarke's "Feathered Friend", he talks about the wisdom of using an animal sentinel to monitor atmospheric quality.
Specifically by using the tried and true "canary in a coal mine" technique. I know most people like to tie little prayer flags and scarves and stuff to the air-vent to make sure it's working, but back home we use wind chimes. You don't have to be looking at 'em to know they're working.
They're not like the chimes they have back on Earth; these only have one note. Most habs around Saturn do it that way — each compartment has a single note. That way, you can tell location of a faulty blower just by the change in the sound.
And let me tell you, they are not optional. If you take a set down for anything other than maintenance on the air-vent in question, you can get arrested. Of course they're loud! That's how you know they're working. But I know what you mean — when I first moved out to Titan, it took me a good month to get used to 'em. I was up all night most nights hearing chimes all over the hab ringing.
It was like this constant drone with a few off notes every now and then to make sure you didn't relax. I complained to anybody who'd listen, which was nobody. All I did was get myself a rep as another dumb groundhog fresh off the boat. The chimes didn't just bother me at night, either. In public spaces they make quiet conversation just about impossible.
And I just about failed my first semester in school from being distracted. Seriously, if I hadn't still been under Immigrant's Probation, I would have had to do a public service sentence. As it was, I did have to take the Habitat Orientation class again — listening to the damned wind chimes the whole time. But let me tell you — They were absolutely right to bust me.
They confiscated my ear buds when I got caught so I didn't have them during a weekend maintenance cycle on the hab. We were living in a retired Trans-Chronian, the kind they used to have before the River -class came out. The counter-spinning rings were always breaking down or getting fatigued or some damn thing, so we only had gravity maybe five days a week.
My little sisters loved it — I'd play catch with them, with the toddler standing in as the ball. Anyway, the apartment had only pair of rooms, and my parents got one and the girls the other. I slept in a bag in the living room and lived out of a foot locker. One night I woke up from a dead sleep with the uncontrollable feeling that something was wrong.
I couldn't put my finger out what it was, but the effect was disturbing. I figured that I was just having trouble sleeping from the wind chimes when I realized that was what was wrong — I wasn't hearing the chimes. A glance up told me that the chimes in the living room were still going, but I really didn't need it. The sound of all the chimes in our apartment had gotten so far under my skin over the weeks we'd been living there that I pretty much figured out immediately which chimes had stopped.
You guessed it — the girls' room. By the time I got in there they were both awake and holding hands while spinning like they teach you. My parents were in there a couple seconds after me, but only because they had farther to go.
Anyway, it was nothing much as vent problems go. A stuffed rabbit toy had gotten jammed into the fan — so the girls got grounded and had to do extra chores for a week. They whined about it, and kids do, and then we all went back to bed. It took a me good while to go back to sleep after that. For all I my complaining about those annoying, distracting, aggravating wind chimes, if we didn't have 'em up that night my sisters would have never have woken up.
Yeah, Fireproof is another absolute classic from grand-master Hal Clement. And it hammers home a hard truth you can find in Lazarus Long's notebooks. On Terra, being ignorant shortens your lifespan. Being willfully ignorant is just asking for it. And being willfully ignorant in space means you are doing your darndest to cop a Darwin Award. You don't just need a good education to get a job in space, you need so you don't die.
Read how that moron saboteur Hart thinks education is a waste of time. Up to when his flaming body gets splattered all over the wall because he thinks he's so smart. He thinks Nah, I don't need no stinkin' physics and chemistry! That's the last thing that goes through his brain, besides the bulkhead.
If Igno-Spy had ever had a high-school Science class he might have realized he was turning the inside of his jail cell into a freaking free-fall thermobaric weapon. With him flicking his Bic at the fuse like Wile E. To conserve his oxygen supply, the curly-haired cadet had set the controls of his boat on a steady orbit around one of the larger asteroids and lay down quietly on the deck.
One of the first lessons he had learned at Space Academy was, during an emergency in space when oxygen was low, to lie down and breath as slowly as possible. And, if possible, to go to sleep. Sleep, under such conditions, served two purposes. While relaxed in sleep, the body used less oxygen and should help fail to arrive, the victim would slip into a suffocating unconsciousness, not knowing if and when death took the place of life.
Unpleasant odors in the air is a problem, but there is not much one can do about it. After all, you can't just open up a window to let in some fresh air, not in the vacuum of space. NASA carefully screens all materials, sealants, foods, and everything else to ensure that they do not emit noticeable odor in the pressurized habitat sections of spacecraft and space stations.
Such odors can quickly become overpowering in such tight quarters. There's a fortune awaiting the man who invents a really good deodorizer for a spaceship. That's the one thing you can't fail to notice. Oh, they try, I grant them that. The air goes through precipitators each time it is cycled; it is washed, it is perfumed, a precise fraction of ozone is added, and the new oxygen that is put in after the carbon dioxide is distilled out is as pure as a baby's mind; it has to be, for it is newly released as a by-product of the photosynthesis of living plants.
That air is so pure that it really ought to be voted a medal by the Society for the Suppression of Evil Thoughts. Besides that, a simply amazing amount of the crew's time is put into cleaning, polishing, washing, sterilizing - oh, they try! But nevertheless, even a new, extra-fare luxury liner like the Tricorn simply reeks of human sweat and ancient sin, with undefinable overtones of organic decay and unfortunate accidents and matters best forgotten.
Once I was with Daddy when a Martian tomb was being unsealed - and I found out why xenoarchaeologists always have gas masks handy. But a spaceship smells even worse than that tomb. It does no good to complain to the purser. He'll listen with professional sympathy and send a crewman around to spray your stateroom with something which I suspect merely deadens your nose for a while. But his sympathy is not real, because the poor man simply cannot smell anything wrong himself.
He has lived in ships for years; it is literally impossible for him to smell the unmistakable reek of a ship that has been lived in - and, besides, he knows that the air is pure; the ship's instruments show it. None of the professional spacers can smell it. But the purser and all of them are quite used to having passengers complain about the "unbearable stench" - so they pretend sympathy and go through the motions of correcting the matter.
Not that I complained. I was looking forward to having this ship eating out of my hand, and you don't accomplish that sort of coup by becoming known first thing as a complainer. But other first-timers did, and I certainly understood why - in fact I began to have a glimmer of a doubt about my ambitions to become skipper of an explorer ship.
But - Well, in about two days it seemed to me that they had managed to clean up the ship quite a bit, and shortly thereafter I stopped thinking about it. I began to understand why the ship's crew can't smell the things the passengers complain about. Their nervous systems simply cancel out the old familiar stinks - like a cybernetic skywatch canceling out and ignoring any object whose predicted orbit has previously been programmed into the machine. But the odor is still there. I suspect that it sinks right into polished metal and can never be removed, short of scrapping the ship and melting it down.
Thank goodness the human nervous system is endlessly adaptable. His hole was on the eighth level, off a residential tunnel a hundred meters wide with fifty meters of carefully cultivated green park running down the center. The main corridor's vaulted ceiling was lit by recessed lights and painted a blue that Havelock assured him matched the Earth's summer sky.
Living on the surface of a planet, mass sucking at every bone and muscle, and nothing but gravity to keep your air close, seemed like a fast path to crazy. The blue was nice, though.
Some people followed Captain Shaddid's lead by perfuming their air. Not always with coffee and cinnamon scents, of course. Havelock's hole smelled of baking bread. Others opted for floral scents or semipheromones. Candace, Miller's ex-wife, had preferred something called EarthLily, which had always made him think of the waste recycling levels.
These days, he left it at the vaguely astringent smell of the station itself. Recycled air that had passed through a million lungs. The circle of life on Ceres was so small you could see the curve. He liked it that way. Infinitely more serious than annoying odors are harmful atmospheric contaminants. They share the same problem that a spacecraft cannot open the windows to bring in some fresh air.
But unlike odors, these can harm or kill. Basic atmospheric monitors will keep an eye on the breathing mix inside the habitat module for oxygen and carbon dioxide levels. But prudent spacecraft will have monitors for carbon monoxide and other deadly gases, hooked up to strident alarms. In space no one can hear you scream, but in the habitat module's atmosphere everybody can hear that high-pitched squeaky wheel in the ventilator.
And there may be permanent hearing loss from loud noises, say, from rocket engines. As a point of reference, the normal ambient noise level on the International Space Station is 60 db.
Acoustic criteria are specified in terms of A-weighted sound level L A or equivalent A-weighted sound level L eq , where it is a specified time period, usually 8 or 24 hours.
The equivalent A-weighted sound level is defined as the constant sound level that, in a given situation and time period, conveys the same sound energy as the actual time varying A-weighted sound. The basic unit for these measurements is the decibel. Space station laboratory modules should have A-weighted sound levels not exceeding 55 dB a noise criterion curve of approximately 50 and reverberation times not exceeding 1.
These values should permit 95 percent intelligibility for sentences under conditions of normal vocal effort with the talker and the listener visible to each other. Environments with A-weighted sound levels above 55 dB will require assistance for adequate speech communication. Designers of audiecommunication systems should recognize that the systems will amplify and distribute noise as well as speech signals to both intended and unintended listeners.
Therefore, their use should be carefully controlled. For sleeping areas, background A-weighted sound levels below 45 dB are preferred, while levels up to 60 dB A are acceptable. Brief noises or transients during continuous noise backgrounds are particularly disturbing to sleep. The probability of full behavioral awakening increases with increasing sound level of the transient. For transients with an L A of 60 dB, the probability of full behavioral awakening is about 0.
The risk for producing significant hearing loss is negligible in noise exposures to an L eq24 of 80 dB. A hearing conservation program similar to that described by the Occupational Safety and Health Administration should be initiated for exposures to an L eq8 of 85 dB or more. If acoustic requirements for acceptable speech communication, sleep, and hearing conservation are met, problems of annoyance and task disruption will be minimal.
Vibration criteria are specified for linear vibration in the Hz frequency range. To reduce the probability of motion sickness, it is recommended that acceleration not exceed 2. Specific tasks requiring more stringent vibrational criteria should be analyzed on an individual basis.
In the absence of appropriate information, these tasks should be simulated on earth to determine vibration sensitivity and required accuracy. If head or finger control is required to an accuracy of 5mm rms or 2. Hypergolics hiss too, with a harsher metallic note, bangs and pings.
Hydroxy rockets , they roar. Solid packs are similar, but rougher, with underlying stutters and clicks. You hear it with your bones. Hard burn, in the jargon, refers to the practice of injecting a limited supply of antiprotons into the exhaust of a fusion torch for short, high-power bursts. Former astronaut Jay Buckey, now at Dartmouth Medical School in Hanover, New Hampshire, US, says that both temporary and permanent hearing loss were recorded after flights on the Soviet and Russian Salyut and Mir stations, even for stays as short as seven days.
The lost hearing was usually at higher frequencies. The living quarters of the ISS are the Russian Zvezda module, which is the noisiest module on the station. NASA says the goal is for the working area to have noise levels at or below 60 decibels dB and sleep bunks to be 50dB.
At their peak several years ago, noise levels reached 72 to 78dB in the working area and 65 dB in the sleep stations. Decibels are measured on a logarithmic scale, meaning, for example, that 60dB is 10 times louder than 50dB. NASA has worked to reduce the noise and its effect on the crew. By November , noise levels had been lowered to between 62 to 69dB in the work area and 55 to 60dB in the sleep compartments.
Astronauts on the ISS used to have to wear ear plugs all day but are now only wear them for 2 to 3 hours per work day. According to the US National Institutes of Health, however, noise levels below 80dB are unlikely to lead to hearing loss, even with prolonged exposure. But while the primary cause of hearing loss in general is high noise levels, Buckey suggested in a paper in Aviation Space and Environmental Medicine that several other factors might contribute to the problem in space.
Elevated intracranial pressure, higher carbon dioxide levels and atmospheric contaminants may make the inner ear more sensitive to noise, he says. But there have been no studies yet to test these ideas.
Buckey had designed a device to measure hearing loss of astronauts on the ISS, but his project was cancelled around the start of when NASA reduced funding for life sciences. Crews have installed fan vibration isolators and mufflers on fan outlets, and acoustic padding to wall panels. The current crew, Russian cosmonaut Pavel Vinogradov and US astronaut Jeff Williams, installed a sound-insulating cover on the Russian carbon dioxide removal system.
They also started adding acoustic padding near the Russian air conditioner. Future crews will swap out 30 to 40 fans with quieter versions. Meteors are probably nothing to worry about. On average a spacecraft will have to wait for a couple of million years to be hit by a meteor larger than a grain of sand.
But if you insist, there are a couple of precautions one can take. First one can sheath the ship in a thin shell with a few inches of separation from the hull. This "meteor bumper" aka " Whipple shield " will vaporize the smaller guys. For larger ones, use radar. I feel like I am on a scavenger hunt for recipes. And whilst i am enjoying it, I really should be cleaning up around here when the boys are asleep ;.
Shelley, I think everyone worries whether their babies are getting a balanced diet! I was always told that as long as you basically offer a wide variety of healthy foods across a week or so then they get everything they need.
When I worried I kept a food diary for a fortnight and at the end took a look to ensure my daughter was getting all the major food groups — some days were up and down but overall she got a balanced diet. Their little bodies seem to tell them what they need I think. I worried like crazy about it with my daughter. The one my daughter took to the most was a Doidy cup got mine in John Lewis. Drawback of the Doidy — when she got excited she forgot to put it down before flinging her arms about — wet mummy!
These started out mushy and then progressed to more textured to lumpy as he got older. I would make them in bulk and put them in the freezer cutting down time each day and not having to worry about having a meal for the rest of the family that was suitable for my baby.
I also let him try feeding himself with the spoon from 6 months he had a spoon and so did I. He would also to pretend to feed me too! What I am trying to say here is that I believe is that you need to do what works for you and your baby the best. I found a combination of the 2 to work really well and my son will still pick up a cucumber and nibble on it for a snack.
Sure thing, Millie, and of course it all sounds like it worked out great. Millie, BLW is all new to me! My LO is 4. I could see doing something like that or reversing the order but doing a combination of both. But of course go ahead, though, do what you feel works best for your family.
BLW is as much about the parents stepping back and letting the child self-feed as anything else. No biggie, just a definitional thing, but worth pointing out.
Hello everybody, I am new to this forum and today is the fifth day of offering my son 6 months and two weeks old food other than my breastmilk. I have to say I am bit surprised with the way my boy behaves in regard the food offered.
In other situation he would grab a thing and the thing being just anything but with the food I offer him, he is very, hmmm, how to say, hesitant. I so far offered steammed potato and carrot. He would hardly touch those things, they did not reach the mouth at all. Well, potato did it, for a second. He would however grab piece of mine ciabatta so I let him have it. He got some small pieces into his mouth and he did not really like it I guess, he coughed a little, but nothing hysterical, just a few coughs.
Then he had apple but only in the special food feeder if you know what I mean. He liked this one on one occasion. And the last thing he had is the salad, fresh, this one he liked to touch — not on every occasion but more than once. I know this needs time but I am still surprised that a child who wants to have everything in his hands and mouth is suddenly so different when it comes to food. I am even eager to say that it seems to me he is not ready for a food. Does any of you have similar experience?
I mean of course there is no real eating at first but no touching either? And one last example — today I made him potato purree but not to feed him but to give him spoon and see if would play this way. And yes I have to say, this worked better, he would hold the spoon, put it in his mouth and this way he tasted a bit of the potato. I am thinking he does not like the texture of cooked things…maybe one possible explanation why he does not want to touch and hold the pieces.
If it was me i would chuck the feeder as well, and skip apple for a while. Im nervous about trying it. They gag, some of them, but choking is rare, in fact they are more likely to slurp back a puree and choke on that than on something that they have placed in their mouths themselves.
That said, fore-warned is fore-armed, and i personally did an infant resus course before starting weaning. May I ask why you do not recommend the feeder?
With the fruit here now it is bit difficult. The spring just began and nothing seasonal really in place yet. The other option I am thinking of is offerenig banana. That is what I have done with my 9month old Son.
It is virtually impossible to over feed a baby. Or yours, which is great. And anyway, at the end of the day i think of it as Easy Weanng, because it was the easiest option for me.
Of course it goes without saying that I'm not accusing you of over-feeding your boy Anna, nor any other person here. I also think that the chance of this happening when baby is also self-feeding is reduced because they're going to be messing about which will naturally space out mouthfuls of puree anyway.
And sensible parents will space out mouthfuls too, I'm sure. Just putting it out there as an example of how it's not as impossible as you may think. FWIW I think quite a lot of people take the same approach as yourself. Something else about puree-weaning makes it easy to overfeed: I do envy people who can just stop eating when they feel full, but i fear that those signals long ago stopped reaching my brain and i now feel full when i see white ceramic poking through sauce….
Your comments have been really positive thank you. Thank you all for your comments. Totally agree with the parenting your way. Made the mistake to listen what the recomandations are and followed them with my first one was a big mistake because he was unhappy untill I stopped. Then we were both happy: Love this blog, congrats. Like the food is fun till one! She feeds on BM all the time. That food gives you cancer, that one prevents it but only if you eat a field of it a day ….
This sounds so intriguing to me. I plan on trying it with my 4 month old son when he is ready. I do have a question though…How did you introduce utensils?
I weaned mostly in the traditional puree way. Unfortunately like any other argument of feeding babies this could potentially have the same damming argument of breastfeeding vs. And that would be a great shame. Neither of my two children overeat, are overweight,or fuzzy eaters.
So please be very careful in negatively portraying traditional weaning and glorifying BLW. I for one will do the traditional mush and spoon mixed with self feeding again,which is what I did with my other two. Thanks for the advice, Mrs Bear. Feel free to address it when you see it.
His hand-eye co-ordination is much better than hers was at this age, which I think makes a difference. Hi, I have a situation where my one year old refuses to eat. He has never eaten. He had open heart surgery at three months and the intubation after the operation left him traumatized in terms of letting things come close to his mouth.
So, I give his food in his bottle with the formula. Mostly very fine purchased baby food. He does not like anything with a texture either. So no cereal in bottle either. He does stick things in his mouth though but not much. He has only two teeth since he is very tiny for his age. I tried various therapists. He still refuses to eat. BLW is my only hope. So my question to you is, what are the foods babies like most that he, with only two bottom teeth, will be able to cope with?
Och, the wee soul. Is he well now, after the surgery? First of all… forget the teeth. No big deal At All. Seeing as most kids are starting to self-feed at 6 months, most have maybe one tooth and manage just fine. What do the therapists say about helping him to overcome his fears? Because it seems to me as a non-professional, i must stress, so ignore ignore ignore if necessary the the hurdle you need to overcome is to make things sufficiently intriguing and appetising to make him want to overcome his perfectly reasonable fears.
I feel for you, open heart surgery at three months and therapists and not eating, it sounds hard. Always small amounts of lots of things — cut up grapes, breadsticks, grated cheese, toast fingers, banana slices etc.
Eventually she started tasting my food, then picking up a bit herself and eating it, stealing a spoonful of yogurt etc. There was no pressure on either of us.
Organix snacks crisp things are good too- they melt in the mouth. It worked for us, but her fear was very mild. Not great for table manners but they can come later.
Tonight was cheese quiche, new pototes, green beans, and carrots, then banana and yogurt. It was everywhere, including in his tummy! The Annabel Karmel top finger foods book is good — got loads of interesting ways of presenting food. My maternal health nurse said i should only be b-feeding till 10 months…that seems an awful long time and everyone else is feeding there bubs finger foods.
I would really love to know what you think the best first blw foods are. I also have no ideas on what she is allowed to eat, i see some people are saying their bubs are eating meats…. My mum was a midwife thirty years ago but feels that mums now are possibly worse off precisely because there is too much, often conflicting, information which just makes everything so stressful.
I know there are lots of great health visitors and they do a very difficult job but have to say mine made me feel absolutely awful about formula-feeding even though I continued to express for weeks so my son still had some breast milk and, however well-intended, stressed one too many times that I could still try to go back to breast-feeding alone.
Our son is nearly 6 months old and has been having a few spoons of baby rice for breakfast for the last 2 weeks. Fingers crossed and good luck! Thanks so much for this post and the website! I found it awhile ago when I was researching this method to start with my daughter, but just now realized how useful it is and will be. She is now 6. I always say, start with looking at what you eat and lift from there. Does she pick up other things?
Are you feeding her milk beforehand? I am thinking of starting this soon, but anticipate a few problems. It seems like I would definitely have to make some specially for him. Even though we kept a salt cellar on the table, we never really used it. So my advice on that one would be to add yours at the table from now on, though you might be surprised.
Restaurant-wise, I would ask for veggies to be cooked without salt, which is easy enough for them to do, and then just wing it with my own food. Have you spoken with daycare?
Hopefully soon she will get a bit more interested in a few others. How many bits of food do you put on their table at a time? And do you just do 1 or 2 different things? Just wanted to say i started my son a bit early about 5 and a bit months as he was just so interested in what we were eating he would watch us like a hawk and then cry if we said no. I used the puree thing for about 3 weeks with fruit and veg as i started early but when he was six months i started with the BLW and have not had a problem.
Some times he does try and quite well too. He eats most things we do, he devoured a home made lasagne. Soft sandwiches and toast made me anxious at first as he put a bit to much in but if you watch their reflex to bring things back up it amazed me and now im learning to make things smaller and he is learning the whole lot does not have to go in all at once.
This way is so much easier than the way i fed my daughter and meal times have really become a family affair with bub included. I found this web about a week ago and was absolultely excited as our child was 7 last week and he does absolutely not want any puree, either it was of fruit, vegetable or flakes, neither the fruit I offer him.
He just loves the pieces of bread we offer him to chew. We are quite discouraged as, as Lucikan says, he does not try to take the food to his mouth very often and he even gags and vomits before the food gets his mouth. We always give him a piece of bread after all, and then he devours it!
No problem of chewing or swallowing, nothing! Well, I hope you can give me some hope… Regards from the south of Spain to you all, good caring mothers. My lovely determined boy chewed today his first piece of meat! After nearly around one week we were determined to continue but, even if you do not want to, bit of frustrated about him not wanting any of the pieces we lovingly offered him. The father obsessed about him axfiating was very nervous at the beginning, because he had two pieces inside his mouth.
I got to calm him down so Matías vomited the first one, because he tried to swallow but he could not. I succeeded to calm my husband down again, and then, after a while, the second piece disappeared of his mouth.
I know some frustrating days will come again, but this is way, I can feel it. I just want to say how pleased I am that I found this website. I am first time Mum to Daisy — 7 months and have been driving myself and my husband!
She had been exclusively breastfed up until 5 and a half months when I started giving her porridge for breakfast which she loved — at first. I stumbled across this website via a friend on facebook and have loved reading all these interesting comments.. So many people sound anxious about food types etc, but i hope they read all the comments made previously, as the info is fantastic…. My only advice to anyone who is stressed, is take a deep breath, and remember this will be over so soon, next year you will be wondering how to deal with a cranky near-toddler!!
I came across this website looking for advice on what to do when your 9 month old suddenly refuses to eat. Because of the reflux and intolerance issues, I was advised against BLW as children with digestive problems have a hard time with lumps bunkum , plus my mother, bless her, was terrified of the idea! We ate together at breakfast and lunch and nothing from our plates was off limits. He would sit beautifully in restaurants, much to the surprise of waiters and us and was completely used to the idea of eating.
His breastfeeds naturally diminished too, he was sleeping thru from 7. My paediatrician took this into account when he weighed him a month ago but he was very concerned that Evan had dropped 2 centiles from the 50th to the 9th, so I was told to encourage him to eat more at mealtimes. Then I realised he would let me feed him as long as he was holding a snack, which we did for a week or so and then that was it — mouth clamped shut, nose turned up, hands up to his face, head turned away from me and shouts of frustration.
From both of us. The truce started last Tuesday. He now sits on my lap while I eat and I encourage him to take things from my plate. No banana or avocado. No rice or pasta. Nothing he previously ate. Any advice would be greatly appreciated. You might have done, though… you just cannot know and there is zero point in second-guessing yourself.
We do what we think is right at the time with the best information we have. Totally agree with Aitch. Try to relax, go with the flow, feed on demand.
OK good to know Jem — I guess this refusal could go on for a while yet. None of my friends with children could remember what they went through, or they all had champion eaters and children who could take formula to fatten them up. Some sort of fried potato has actually been all he will eat, so I make little potato cakes mixed with chicken thigh and egg to up the protein.
Thanks for taking the time to read my long missive and for passing on the encouragement and advice: Kids apparently are grazers so prefer this method. Not tried it myself yet though. Bless you Aitch, he ate a chipolata! Knead some bread dough with a handful or two of whole green pitted briny olives and fashion into thick wands two fingers width.
Leave to prove for an hour, spray with water then shove them into a really hot oven for 20 minutes. I like them with with a cold beer. I discovered this website last night and can already feel myself starting to relax about feeding my 7mth old.
I attempted to start weaning Charlie with baby rice and purees just before he was 6mths and at no point has he showed any interest. If anything he gets upset as soon as you put a spoon near his mouth. This morning he sat a the table with me and his big sister and smiled away whilst gumming on sticks of cucumber and banana. With BLW are you saying pretty much anything goes? Of course besides the obvious- salt, sugar etc.
As you mentioned falafel, I thought about meat or fish croquettes. Here we make them of ham, cod, chicken breast, spinachs with pine kernels these last ones very fashion at the moment.
I also thougt about pasties. The most usual one here is the tuna-fried tomato, but you can make it of meat too? I found this recipe: I was amazed reading you give your children cheese or fish.
How can advices differ so much from one country to another? Eva Maria, I understand how you feel. I am Spanish and I live in the Uk. I brought up my first son with baby led weaning as a matter of coincidence. He played with them and that was it. Since he was nearly 7 months and he was not into solids in the Spanish style purees REALLY smooth , I tried by giving him bits of bread and he devored them!
A book was about to be published. It was in fact the book that appears in this website. We ordered it, and when I was reading it, everything made perfect sense. It was also good to start with the chewing as it helps the tongue movements so speech will benefit from it and since I am bringing up my children bilingual this is perfect!
I must say I had and still have to deal with the criticisim of my family and friends as they do things in a different way! His first and since then favourite food 6 months onwards was salmon and broccoli.
When I told my granny in Spain she said: But they all see how he eats now and time has given me the reason. Give it a try. It is worth it. Regarding what you mention about foods that are ok in one country and not recommended in the other one, I am puzzled, like you, but as I say, I live in the UK and so I do things like they do here. I have never looked back. In fact, when I see that in Spain they are still with the pureed food almost till they are 1 year old, that is what I cannot understand.
Children are able to eat proper solid food a lot earlier than that. Sorry for the super long email! Tbh all this differing advice was one of the main factors in me just deciding to go for it.
My sister in New Zealand had different weaning advice again from the UK and other friends in other European countries. Given that kids all over the world seem to successfully make it to maturity, I stopped stressing about the whats and whens and just gave them food.
Just one little explanation. I have answered my peditrician today and he told me yes to cheese, any animal it was. No animal milk but yes for the cheese.
No fish, no berries, no eggs though. We did blw with our son who is 2 and half now. He has Cystic Fibrosis so his diet is almost the opposite of what you would normally give a baby, he needs high fat, high calorie food and needs lots of salt in hot weather!
We loved the whole process of weaning him. Lots of friends and family were fascinated, but very dubious. She watches us all eat and she is just desperate to get stuck in herself. Just like his mummy. And 2 packets of crisps a day, on doctors orders. Edward is doing really well thanks, Aitch.
I remember my dentist telling me that about crisps when I was a kid, it made me feel better about having chocolate! BLW seems a great idea and wish id known sooner but…. Some allergists now suggest that the 4 day wait rule can cause allergies.
If you give a baby a small amount of some new food and then wait a bit -no problem. If you all of a sudden give your baby nothing but bananas for 4 days the immune system can overreact. There is even more evidence that delaying the introduction of allergens makes allergies MORE likely, not less.
So you may be better off giving peanuts at 6 months, not two years. That being said IF you have reasons to suspect allergies, or a strong family history of allergens, do your own research. Decide what makes sense to you from the current research -early allergens vs late; rotation diets, vs standard 4 day rule, vs unrestricted. I have just started BLW with my 6-month old. He has started waking up in the night for feeds even though he has slept through for the last three months or more.
With regards to the BLW, he is enjoying everything I put his way — fruit, veg, meat, bread — and there is definitely evidence that some of it is making its way into his tummy! Lady J, from within my circle of friends introducing solids had no effect on sleep whatsoever. Sleep patterns do tend to change a lot in the first year as well. The vast majority ended up constipated from the baby rice too. You could always offer purees on loaded spoons..
I did that with hummous quite early on, just chickpeas, clove of garlic, olive oil whizzed together. I think most people are skeptical in the beginning, but once you calmly explain the difference between gagging and choking, and they see it in action, it tends to die down.
My mother now brags about how well her grandson eats. Milk, on the other hand, is nearly completely digested, so is the answer to getting through the 6 month growth spurt. I am researching weaning at the moment and really like BLW, I have a 4 month old who is bottle fed.
Can I do BLW or is it for bf babies only? Just ordered the book so I hope this helps. Aitch bottle fed hers and they took to it like little troopers.
Just whatever milk you use, keep it coming aplenty till they get the hang of food properly can be around a year, can be later!! What a great website! I am completely dismayed to find I have been naively giving my 10m old whole grapes for a few weeks now, without too much worry.
She manages fine but the point about a whole grape being a bugger to remove from the lungs makes so much sense that I shall not risk it again. The other thing that made me relax, and thrilled me, was seeing her weight continue between the same centiles it always has been. We just let her do what she wants to do regarding her meals. So, I am loving weaning my first baby this way. Some days she has maybe 8 feeds, and I am worried about how things will go after I return to work.
This is how my mom weaned me. When he does, she said just cut him a couple small pieces and let him take over from there! Much as I like to think all the women in my family are brilliant, I pretty sure she did it this way because it was easier than puréeing her own food and cheaper than buying jarred baby food. I have two questions about how BLW weaning works. Would it be okay for her to have these things? What is the thinking behind not letting her have water?
Is it because you are breastfeeding? Aitch, so what do you think about veggie juice? I have just read the BLW book and my mom said she weaned us the same way I am the eldest of 3 at 35 yo. So far other things I have read on the www are all against salt, however to her point, at such a young age the salt provides valuable trace minerals. Has anyone tried this or egg yolks at 6 months? She is not yet able to sit herself up in a highchair, is she too young to start controlling her own food to mouth?
Thanks, she is waking up every 3 hours for a feed at night. I have just started her on some solids, mush, but am keen to have her self feeding as soon as possible. Milk is so, so important at this age breast or formula, whichever you choose and rushing to replace this with food could leave her genuinely hungry and losing weight.
She will take to it in her own time. In the mean time I would suggest laying back on the mush less calories and just offering more milk if she wants it. Hi, Great site, useful info. About to start weaning my 3rd child who has been exclusively breastfed. My other 2 children were weaned with traditional mush and it was time consuming and not particularly effective. This very issue is being studied in London and they are looking at introducing specific food substances commonly associated with ALLERGY earlier into babies diet as in certain areas in the world where the diet is more varied at an earlier stage they have a far lower rate of allergies.
That aside, allergies are genuinely a potentially serious problem and reactions to them are usually soon after exposure. It feels right to me, seems like less hassle, seems as if it puts less pressure on baby and parents and actually looks like it would be fun. However, I am concerned as my son has reflux. I am brand new to this site, but saw your post and had to reply. My son is 7mo now and also has reflux. We have been shoving prilosec down his gullet since he was 1 week!
I started him on purees at about 5 months, when he started reaching for my food and making chewing motions when I was chewing. He did ok, still does, but not knowing that BLW was anything with a name or following! I started giving him bites of my soft food once he was starting to push the food around in his mouth more.
Since I started feeding him my food he has been keeping the food down better than ever, and eating more. Just today I sat down to eat a nectarine skin off! And that was right after he nursed. I have had to be more careful with what he eats than it seems many BLW moms are, remembering to keep in mind his sensitive tummy. Keeping foods bland and avoiding food that can cause indigestion and gas.
And since many reflux babies are also constipated bananas are right out too, at least for us. And since many raw foods are more irritating to a reflux-y tummy I am sure steam or microwave anything but the mildest of foods. In my experience with this sort of feeding my 5yr old was the same it is actually better for reflux babies since if a food makes their tummy upset, the just wont eat it. My advice would be not to push it, wait till baby is showing signs that they are ready to start eating they will be just fine on breast milk or formula till they are ready and just make sure you are still careful what you give.
If you are not concerned about dairy, it is a good time to introduce yogurt since it has probiotics that aid digestion. We have allergies in the family so I have just started adding probiotics to his food.
I have personally just looked up advice for eating with chronic reflux for adults and adapted that as I could. And no one knows your baby as good as you! Just listen to the dear boys body and it will be fine! Hi, Im very interested in BLW for my first child. So im wondering what would be a few good foods to start with that I know she can manage with no teeth..?
So happy to find this site! For 2 who is now 6. Thanks for the site and info. This information is really useful, I have been EBF my 5. I must admit I am very nervous, but excited at the same time…. Is there any one else on here who has BLW twins? She did this once when I gave her calpol too a while ago, and she just projectiles all her stomach contents up. Is this normal, what should I do? I have just had my LO on my lap, she reached out for a bit of toast I was eating so let her have the crust.
She got a little bit in the front of her mouth and was chewing, she then was sick again, heaved twice and her stomach contents up. She is 6 months tomorrow but not sitting up on her own, is she just too young? I would probably just leave it for a week or two and then try again. She is still little, she has loads of time to get the hang of it: Love this — I had never heard of BLW before, I have now brought this up with my ante-natal group all 4 months post natal and hopefully a few of us will have a go at this.
Sounds so much more natural than mushing up food… Really good website, nice one: Hi I just started BLW and it seems to be going well. I have tried pears, peaches, bread, cucumber,banana,and chicken breast….. Not all at one sitting though. I understand that this approach is more relaxed. I started with fruit. Should I include all the food groups each time? How does it work.? Am I crazy for feeling this way? Formula will spoil in very hot climate.
You can purchase hand feeding formula from a pet shop or pet supply in one pound cans or 5 pound packages. In emergencies you can make your own formula by grinding up some bird pellets. Only in extreme emergency - if nothing else is available - some of the better brand dog food pellets can be used with a little peanut butter added. However, there is a chance for bacterial contamination. Soaked monkey biscuits run through a blender also will work. Add just a small amount of peanut butter to give better flavor and more protein.
There is however also a chance of bacterial contamination. Heat water to F if not sure, heat water to where it is too hot for your fingers. Pour over the formula then stir with a spoon until you have a gravy-like substance. Wash your hands good with soap and water.
Place one of your fingers in the formula and check temperature. Temperature of the formula at feeding should be at F. Check with a food thermometer or finger test. Formula should be hot to your finger and get it red, but should not burn you. If you can count from 1 to 30 with your finger submerged in the formula without getting burned, it is just right to feed. Place the bird in front of you on a towel facing you. Fill your eye dropper, pipette or syringe with food.
Place the head of the bird between two of your fingers Index and middle finger in a V position so you can lock the Head in between those fingers. Use your thumb to pry the beak open.
Once beak is open insert the full pipette or eye dropper into the bird's mouth above the tongue. Slowly squeeze the food into the bird's mouth. Refill and repeat until birds crop is full. Just a small, additional explanation on hand feeding: Make sure that you put the syringe pipette into the beak on the baby's left side - your RIGHT side - aim it toward the back of the throat, across the tongue at a slight angle to the left your left.
You will want to feed the formula slowly and watch the baby carefully as he will stop pause drinking the formula to take a breath. If you keep feeding the formula when he is trying to take a breath he will inhale the formula and this can kill your baby. Birds have 3 holes in their mouths - one in the roof of their mouth, one in the middle of their tongue and one in the back of the throat on the left hand side as you look at them. The holes in the roof of the mouth and the tongue are for breathing - the one into the roof of the mouth goes into the upper respiratory tract snares, upper sinuses.
The hole in the tongue goes into the lower respiratory tract - lungs. Normally, while eating, these holes are closed. The hole in the rear left hand the bird's right side is the esophagus and leads to the crop and intestinal system. Make sure you have a firm grip on your babies. Healthy hungry babies some times will have strong feeding responses they pump some times very strongly A firm grip will prevent injuries. Understanding your bird's anatomy and how it works may help you in hand feeding.
Remember to go slow and watch your baby - he'll tell you what he needs air or more food.