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There have been no space station fatalities at all so far, let alone any that were the result of pencil shavings. In fact the only (human) fatalities "in space" were the crew of Soyuz 11.

Yeah. That last little bit in the second quote does not match what NASA says. That the US has been using "space pens" since 1967 and that the Russians have been using them since 1969, pre Salyut, Mir and International space stations.
http://history.nasa.gov/spacepen.html

That said the hazards of broken pencil tips, graphite dust and wood shavings was a real concern with respect to electrical shorts, fires and physical hazards (ex: broken tip vs. eyes).

"Originally, NASA astronauts, like the Soviet cosmonauts, used pencils, according to NASA historians ... Pencils may not have been the best choice anyway. The tips flaked and broke off, drifting in microgravity where they could potentially harm an astronaut or equipment. And pencils are flammable--a quality NASA wanted to avoid in onboard objects after the Apollo 1 fire."
http://www.scientificamerican.com/article.cfm?id=fact-or-fiction-nasa-spen

Wikipedia
NASA*
About
Spacepen
The Space Review
BBC History Magazin

If you've done the research provide an opposing source.

* NASA admits that they originally ordered pencils for over $100 each but backtracked. Latch on to that if you want to bash wasteful government spending, but remember they did respond to the public backlash.

You are essentially saying that they don't care about their own offspring either. It would help we me all might dial back the hyperstimulation of our amygdalas and focus on some of the more observable facts concerning the issue.

if one does this say at http://climate.nasa.gov/keyIndicators/ , it seems hard for me at least to understand what in these graphs the AWG deniers see that doesn't suggest its just going to keep getting warmer and warmer in the relatively near future. As much as I find the politics of most voters in Texas distasteful and counterproductive from my perspective, I don't really want to see my fellow Americans fry simply because they seem to be confused about the science of global warming.

That said, however, those who want to insist its really not getting warmer need to soon start getting credible in terms of observations they can point to defend their position. Its not as if praying can be expected to do much good, or at least one might conclude on the basis of this past summer's experiment or the approach of calling everyone an idiot or a dupe or a socialist or some other totally irrelevant epithet.

Well that's the thing. It's not places like New York City that need to be moved, but rather low-lying pacific islands.

No, I disagree:

Look at this NASA picture: http://visibleearth.nasa.gov/view.php?id=55167.
Then, think: why is it that you can recognize the outline of the continents?
Almost all transcontinental container traffic goes by boat. Harbor cities is where the commerce is, so that's where the people move to for work.
When harbor cities such as Shanghai, New York, Rotterdam, Singapore, Hong Kong, Antwerp need rebuilding because of rising sealevel, watch what happens to the price of bananas. Or coffee. Or cars.
Doesn't matter if it takes 50 or 150 years; most of the large harbor cities are much older than that. It would still be an enormously painful and expensive investment.
And that's only talking about the economy; but giving up or relocating all the coastal churches, libraries, musea etc. because of 7 meter sea level rise also has a price tag.
To conclude: the picture in this (Dutch) Wikipedia article shows what half of the Netherlands looked like in Roman times: http://nl.wikipedia.org/wiki/Verdronken_Land_van_Saeftinghe. The real-estate brokers don't want those times to return :-) not after 57 years of paying taxes to raise the country's flood defenses to the current (inadequate) level: http://en.wikipedia.org/wiki/Delta_Works (N.B. note the cost calculation in that article :-) )

"There is compelling evidence [that] fine particles of moondust, when sufficiently charged-up, actually float above the lunar surface. This could create a temporary nighttime atmosphere of dust ready to blacken spacesuits, clog machinery, scratch faceplates (moondust) is very abrasive) and generally make life difficult for astronauts."
http://science.nasa.gov/science-news/science-at-nasa/2008/17apr_magnetotail/

If this is the case then SETI may be wasting their time looking for any kind of ancient tracks in the dust on the moon.

That any advanced alien race has *ever* visited the vicinity of our world. As Douglas Adams put it, "Space is big. Really big. You just won't believe how vastly hugely mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space."

That's not to say I don't think that extraterrestrial life exists. It almost certainly does. Is some of that life intelligent? Maybe. Is that intelligent life (barring superluminal space travel) close enough to our solar system to warrant sending a probe/ship/monolith? Unlikely, but possible.

I think someone was having trouble coming up with a good idea for a grant application and wrote up a proposal after watching 2001: A Space Odyssey.

All that said, if the data from the Lunar Reconnaissance Orbiter is complete enough, it couldn't hurt to analyze the data to see if there's anything anomalous. In fact, I think it's a good idea. We will probably get some unexpected and possibly even interesting results that have nothing to do with extraterrestrial intelligence.

For reference here is the sort of image they will be looking at: http://www.nasa.gov/images/content/584640main_apollo17-right-670.jpg

Believe it or not, this long route (via the Earth-Sun L-1 (Lagrange-1) point is a lower energy trajectory (that is, it takes less energy to send the probes) than the more direct route followed by the Apollo missions. This allows for a smaller launcher (or conversely, a larger payload for the same sized launcher). See http://www.nasa.gov/pdf/582116main_GRAIL_launch_press_kit.pdf.

Strangely enough, I'm unable to reach neither http://nasa.gov/ nor http://science.nasa.gov/. Other web sites and services are working perfectly well. Anyone experiencing the same issue? I'm using Corbina/Beeline, one of the largest internet providers in Moscow...

Strangely enough, I'm unable to reach neither http://nasa.gov/ nor http://science.nasa.gov/. Other web sites and services are working perfectly well. Anyone experiencing the same issue? I'm using Corbina/Beeline, one of the largest internet providers in Moscow...

Strangely enough, I'm unable to reach neither http://nasa.gov/ nor http://science.nasa.gov/. Other web sites and services are working perfectly well. Anyone experiencing the same issue? I'm using Corbina/Beeline, one of the largest internet providers in Moscow...

Strangely enough, I'm unable to reach neither http://nasa.gov/ nor http://science.nasa.gov/. Other web sites and services are working perfectly well. Anyone experiencing the same issue? I'm using Corbina/Beeline, one of the largest internet providers in Moscow...

It's a COPV, see here or page 11 here. The wrapping has probably shielded it enough during the atmospheric re-entry and then ripped away, or it could be from lower altitude flight. In fact NASA and ESA have already studied this object, and most responsible news outlets have explained it along with the newsreport. The only real question is which mission or ship it is from, but unfortunately that might never be found out.

The actual total cost of the shuttle program through 2011, adjusted for inflation, is $196 billion.[5] The exact breakdown into non-recurring and recurring costs is not available, but, according to NASA, the average cost to launch a Space Shuttle as of 2011 is about $450 million per mission.

And here: http://www.nasa.gov/centers/kennedy/about/information/shuttle_faq.html#10

Q. How much does it cost to launch a Space Shuttle? A. The average cost to launch a Space Shuttle is about $450 million per mission.

In other words this five year agreement costs about as much as three Shuttle launches.

Nasa has a list of plants that actually clean the air. A PDF of the original study is here, or you can go to a simplified list on Wikipedia. I think we are all aware of "sasquatches", individuals who while technically gifted are hygienically challenged. Having been 'squatched (trapped in an enclosed area by a sasquatch with precious little fresh air rejuvenation) far too many times, I also offer up a list of scented plants that can help. Humans tend to respond most favorably to rose-scented flowers (hence the popularity of roses). Sickly-sweet perfumes (such as lilies) can be unpleasant to some people. Miniature roses and rose-scented geraniums are probably the easiest to care for. Avoid poisonous plants (e.g. Angel trumpet) as at some point, a teenager (with little or no impulse control) is going to think it's funny (or for revenge) to slip a few bits of the plant into someone's drink or food without giving much thought to the potential outcome. If your high school has a gardening club, it would be wise to involve them. This could be a good lesson plan for students interested in biology and interior design.

Remove all fluorescent light tubes and replace them with LED banks. Preferably full spectrum or with a blend of colors. Make sure the lighting is always indirect and that the source points (the LEDs themselves) are not directly viewable. This makes for good, soft all-around lighting with little or no glare. Very easy on the eyes. Fluorescent lighting is very harsh on the eyes. I would build the banks based on five LEDs: cool white, warm white, red, green, and blue. I would also sprinkle in a couple of black-light purple LEDs. Turn this into a lesson and have the kids build such banks with an Arduino to control them. The kids could learn to program various light levels and colors to simulate various natural lighting situations. You could program the LED banks along the walls to actually change the color of the room. Also, full-spectrum lighting is good for the plants, just as it is calming for the humans in the room.

The room design is important as well. I would have the walls painted white with a slight bluish or cool grayish tint to it. Neutral grey colors are best for rooms where computer graphic design or image processing are taking place, to avoid the eyes being fooled about the color balance of an image. While greys are a cold and sterile color, the room can be warmed up by adjusting the color balance of the LED lights mentioned above. One wall should have a 16:9 rectangle painted in reflective paint to be used as a screen or have a retractable screen in front of an optional chalkboard for lessons. In a computer class, the teacher can then show code samples on the screen and demonstrations of changes to the code. Outgoing vents should be placed along the chalkboard or whiteboard, so dust from chalk and fumes and dust from the markers exits the room via the vents to protect the computers from dust. Good ventilation is also important due to the incidence of 'squatches mentioned above.

Chairs should have gel padding in the seats. There should be footrests beneath the desks. Being comfortable is vital when coding. Cheap, hard, plastic seats become uncomfortable very quickly and that becomes distracting while trying to work out some code.

For equipment, I would suggest Unix-based computers with a centralized administration console. Students should only have non-administrative accounts on their computers. Windows could be run via WINE or Parallels or Fusion, depending on the parent OS of the computers. Virtualized environments can easily be cleansed should a student introduce or create malicious software. Students should be encouraged to try and figure out how to escalate their permi

NASA still has 57 astronauts on the active list. They used to have over 100, and they probably need less than 25 at this point.

(NASA needs to revise their web site. It still talks about flying the Space Shuttle.)

20/20 vision? Like Daniel Burbank, Steve Frick, or Don Pettit

20/20 vision? Like Daniel Burbank, Steve Frick, or Don Pettit

That's true but then you can do both, hitch a ride on a survey craft to say Jupiter & Saturn, then when passing Saturn use it's gravity well to slingshot the craft - with telescope attach in a perpendicular direction.

Thinking about it, the Voyager's are in such a trajectory, both leaving the solar system away from the plane containing the planets.

http://voyager.jpl.nasa.gov/mission/images/interstellar_1.gif

I really can't stand this *cost effective* bs. People keep coming out and saying how expensive the shuttle was, and how much of a waste of money it was. In reality it was actually very cheap in comparison to other things we spend money on. Source: XKCD

Shuttle
Total: $194 billion
Per Launch: $1.43 billion
Per Year: $6.46 billion

Apollo Program
Total: $192 billion
Per Launch: $11.94 billion
Per Year: $17.45 billion

Federal Fraud
Per Year: $125.4 billion

Iraq War
Per Year: $98 billion

Ballistic Missile Submarines Per Year: $12 billion

Federal Interest on Debt
Per Year: $198 billion

US foreign military aid
Per Year: $11.5 billion

So yes, it was expensive. But we spend money like it's going out of style (heck, the 2009 stimulus was 115 times the annual cost of the program. It was even 4 times the total cost of the program)!!!

So sure, let it die with nothing to replace it. Because nothing ever came from it...

I knew the core was supposed to be the cause of our magnetosphere

That's a large part of the answer right there! The magnetosphere acts as a shield to keep a lot of harmful particles from the solar wind away, things which would work to strip away the atmosphere. Mars is an example of what can happen to planets that lack this. (Obviously, Mars' lower gravity works against it in this regard as well)

http://science.nasa.gov/science-news/science-at-nasa/2001/ast31jan_1/

Uh, the tail WAS blowing away from the sun. Take a look at the coronograph footage for a view that isn't wildly foreshortened:

There is the Chandrasekhar limit which defines the maximum size of a White dwarf star .

There is a theoretical maximum limit for a neutron star, which seems to be about 3 - 3.2. This also applies to pulsars, which are spinning neutron stars.

There is also an upper limit to the size that a black hole can become

There is the Schwarzfield radius which defines the escape limit for the speed of light.

Maybe the maximum size of neutron star is the minimum size of a black hole? Or is there something inbetween?

Here is the scientific paper. It makes no claim whatsoever about the mass of IGR J17091-3624. On p. 6, they say:

Figure 5 implies that if IGR J17091-3624 emits at Eddington, then either it harbors the lowest mass black hole known today (< 3Msolar for distances lower than 17 kpc), or, it is very distant. Such a large distance, together with its b ~2.2deg Galactic latitude, would imply a significant, but not necessarily implausible, altitude above the disk

Here is the NASA press release summarizing the paper for people who aren't scientists. It quotes the lead author as saying:

Just as the heart rate of a mouse is faster than an elephant's, the heartbeat signals from these black holes scale according to their masses

The Forbes article morphs this into "NASA Satellite May Have Found The Smallest Known Black Hole," and says, "An international team of astronomers utilizing NASA's Rossi X-Ray Timing Explorer (RXTE), believe that they've identified a candidate for the smallest known black hole[...]"

The slashdot summary says:

The black hole itself is only about three times the mass of the Sun[...]

This is completely incorrect. It's a candidate for a very low mass black hole. What that means is that they're suggesting that astronomers do follow-up observations on this object and actually determine its mass, which may be unusually low.

It is of very great interest to relativists and astronomers to find the smallest black holes. There is a limit called the Tolman-Oppenheimer-Volkoff limit on the largest mass that a neutron star can have. There are big theoretical uncertainties in this number, but it is probably around three solar masses. However, we don't know for sure whether anything too massive to be a stable neutron star necessarily becomes a black hole. There have been all kinds of goofy objects hypothesized by theorists that might be intermediate between neutron stars and black holes, including black stars, gravastars, fuzzballs, quark stars, boson stars, and electroweak stars. Observing a low-mass black hole narrows the gap in mass between the heaviest stable neutron star and the lightest black hole, leaving less wiggle room to believe in these exotic objects.

Europa, although an "obvious" choice, is problematic.

Yes. The radiation in the equatorial plane of Jupiter is incredibly intense. Someone who should know told me once that an unprotected human on the surface of Europa would die from the radiation before they died from vacuum exposure, which takes seconds. The Juno spacecraft has a radiation vault to protect its computer, or its lifetime in orbit would be measured in days. (Previous missions spent very little time in the equatorial plane, and could survive plunging through the very thin plane at speed OK.) A Europa base would almost certainly have to be in / under the ice to give the crew a chance of survival.

Seems that NASA is investigating the possibilities of methane as a rocket fuel: http://science.nasa.gov/science-news/science-at-nasa/2007/04may_methaneblast/
And it's a very clean fuel too, so, yeah, I was thinking along the same lines.

The problem is not landing on the comet, the problem is that the comet's gravity is so weak that conventional sampling techniques will tend to push the spacecraft away, and it is not clear that you will be able to anchor the spacecraft firmly enough to avoid this. Similar problems exist with tether based sample return (where a long tether is used to match velocities with a target, and there are only a few seconds available to collect a sample).

There are various proposed solutions for this "touch and go" sampling problem. The recent Decadal Survey provides an overview. Hayabusa tried to fire pellets into Itokawa, to kick up some material for sampling. Other proposed solutions include cores and scoops, "sticky pads," brush wheel samplers. A reasonable approach would probably be to try several attempts, if possible.

They don't get specific in this article but they do say that the "methane is quickly destroyed in the Martian atmosphere in a variety of ways" http://www.nasa.gov/mission_pages/mars/news/marsmethane.html

Just to clarify for other readers, you post makes it sound like "NASA Doesn't do much" at NASA ARC.

I work at ARC, and it's a wonderful research facility! In just my short time here I've been involved with groups doing pioneering work in computer science and robotics, supercomputing, avionics, aviation safety, cockpit design, UAVs (for science, not war!), earth science, biology, astrophysics, planetary discovery, and so much more!!

NASA Kepler, which just found a "twin" earth (Google: Kepler 22-b) was begun here, and the science operations are still performed here.

Quite a lot of great stuff comes out of NASA Ames, for a very small overall price tag.

Just to clarify for other readers, you post makes it sound like "NASA Doesn't do much" at NASA ARC.

I work at ARC, and it's a wonderful research facility! In just my short time here I've been involved with groups doing pioneering work in computer science and robotics, supercomputing, avionics, aviation safety, cockpit design, UAVs (for science, not war!), earth science, biology, astrophysics, planetary discovery, and so much more!!

NASA Kepler, which just found a "twin" earth (Google: Kepler 22-b) was begun here, and the science operations are still performed here.

Quite a lot of great stuff comes out of NASA Ames, for a very small overall price tag.

Just to clarify for other readers, you post makes it sound like "NASA Doesn't do much" at NASA ARC.

I work at ARC, and it's a wonderful research facility! In just my short time here I've been involved with groups doing pioneering work in computer science and robotics, supercomputing, avionics, aviation safety, cockpit design, UAVs (for science, not war!), earth science, biology, astrophysics, planetary discovery, and so much more!!

NASA Kepler, which just found a "twin" earth (Google: Kepler 22-b) was begun here, and the science operations are still performed here.

Quite a lot of great stuff comes out of NASA Ames, for a very small overall price tag.

Just to clarify for other readers, you post makes it sound like "NASA Doesn't do much" at NASA ARC.

I work at ARC, and it's a wonderful research facility! In just my short time here I've been involved with groups doing pioneering work in computer science and robotics, supercomputing, avionics, aviation safety, cockpit design, UAVs (for science, not war!), earth science, biology, astrophysics, planetary discovery, and so much more!!

NASA Kepler, which just found a "twin" earth (Google: Kepler 22-b) was begun here, and the science operations are still performed here.

Quite a lot of great stuff comes out of NASA Ames, for a very small overall price tag.

Just to clarify for other readers, you post makes it sound like "NASA Doesn't do much" at NASA ARC.

I work at ARC, and it's a wonderful research facility! In just my short time here I've been involved with groups doing pioneering work in computer science and robotics, supercomputing, avionics, aviation safety, cockpit design, UAVs (for science, not war!), earth science, biology, astrophysics, planetary discovery, and so much more!!

NASA Kepler, which just found a "twin" earth (Google: Kepler 22-b) was begun here, and the science operations are still performed here.

Quite a lot of great stuff comes out of NASA Ames, for a very small overall price tag.

Just to clarify for other readers, you post makes it sound like "NASA Doesn't do much" at NASA ARC.

I work at ARC, and it's a wonderful research facility! In just my short time here I've been involved with groups doing pioneering work in computer science and robotics, supercomputing, avionics, aviation safety, cockpit design, UAVs (for science, not war!), earth science, biology, astrophysics, planetary discovery, and so much more!!

NASA Kepler, which just found a "twin" earth (Google: Kepler 22-b) was begun here, and the science operations are still performed here.

Quite a lot of great stuff comes out of NASA Ames, for a very small overall price tag.

Just to clarify for other readers, you post makes it sound like "NASA Doesn't do much" at NASA ARC.

I work at ARC, and it's a wonderful research facility! In just my short time here I've been involved with groups doing pioneering work in computer science and robotics, supercomputing, avionics, aviation safety, cockpit design, UAVs (for science, not war!), earth science, biology, astrophysics, planetary discovery, and so much more!!

NASA Kepler, which just found a "twin" earth (Google: Kepler 22-b) was begun here, and the science operations are still performed here.

Quite a lot of great stuff comes out of NASA Ames, for a very small overall price tag.

It has been known for a long time that the formation of hydrocarbons does not require life: http://www.nasa.gov/mission_pages/cassini/multimedia/pia11001.html The red spots on Jupiter, Saturn and Uranus is Methane. The gas giant planets are giant Esso stations in the sky.

I'm concerned about declining government research facilities i.e. NASA. Reason is private companies are profit driven, government is not. Before you all start screaming "damn socialists" you need to realize there was a time which researchers can work on developing new technology and not be concerned with PHB asking for productivity reports. Now we can argue about the goals (i.e. weapons) but looking at NASA's predecessor N.A.C.A. which they had facilities and labs (many at Ames Research Center, it was Ames Aeronautical Laboratory in the days). These facilities housed scientists, engineers, technicians to work on various things too expensive and risky for private companies, it was this work that helped US become a leader in aerospace technology (specifically why NACA was created in 1915). Again we can argue about govt research but look at it this way, if we don't do it someone else will (and they are). At Edwards AFB in the 1950s, Scott Crossfield said of the inventory of the highest flying, fastest flying aircraft, "Not even Howard Hughes has what we have!" Twenty years before, Hughes had the fastest airplane.

Many people argue over govt waste, corporate handouts, and evils of socialism but consider the US has the best airplanes because the research and development was subsidized by the US govt. Heck, other countries do the same. Now there was a time when private companies did research without concern of quarterly profits. Bell labs (the transistor), Xerox Palo Alto (desktop computer with windows and mouse), IBM Almaden (harddrive). But these private research labs are now applied technology centers. I don't really know if Google has a dedicated lab devoted to longterm research and they may not be around long enough.

Speaking of Hanger One, Navy made big use of it when Moffett was active. It housed many P3s which can be serviced and shielded from rain and wind. Airshows they had back then (1980s) had huge turnout of 100,000s and more (admittance was free). Companies along Ellis st got pissed with so many cars parked in their lots but flying demos were impressive and lots of displays even USGS had a display. You can tour P3s and talk with the officers. Amateur radio people provided communications support including amateur TV, I talked with one guy who was on top of Hanger One with his ATV camera, he said he was able to see the planes i.e. Blue Angels fly across right at his eye level. He said was scary climbing up as walkway inside was thin with a single cable on each side.

From a bio of Joseph Ames which ARC was named after, and a true American who put service before self:
from http://grin.hq.nasa.gov/ABSTRACTS/GPN-2000-001639.html
Ames expected the NACA to encourage engineering education. He pressed universities to train more aerodynamicists, then structured NACA to give young engineers on-the-job training. Ames gave the NACA a focused vision that was research-based and decided that aerodynamics was the most important field of endeavor. Two years later he accepted the Collier Trophy on behalf of the NACA. He kept the NACA alive when Herbert Hoover tried to eliminate it and transfer its duties to industry.

Ames accepted a nomination by Air Minister Hermann Goring to the Deutsche Akademie der Luftfartforschung. Ames then considered it an honor, many Americans did, and was surprised to learn about the massive Nazi investment in aeronautical infrastructure, then six times larger than the NACA. Ames urged the funding for a second laboratory [ at Moffett Field ] and expansion of the NACA facilities to prepare for war.

According to NASA, liquid groundwater would probably be a few kilometers beneath the surface of mars. The deepest oil wells are around 9 kilometers deep, so drilling down to it would be possible, as long as you knew where to drill for it.

It looks fine if you eliminate the silly thermoelectric generator and slap on one of these asc engines, http://gltrs.grc.nasa.gov/reports/2006/TM-2006-214243.pdf. They get you somewhere on the order of 6-8x more power for the same Pu. Plenty of room to play.

Nasa says there are dunes of the stuff. So, more than just a crusty deposition in rock fissures.

http://science.nasa.gov/science-news/science-at-nasa/2011/08dec_slamdunk/

As for starting tectonic activity, a large orbiting body would start it up through mechanical heating. We are talking science fiction here.

But since the ice/snow on the poles grows & shrinks, then it's already clear that the water exists in non-frozen form at times. To think that it goes from solid to gas instantly without any liquid form on a planet (Mars) where there are dry river beds, would be logical. (NASA's known about the river beds since 1998 at least, see http://apod.nasa.gov/apod/ap980205.html)

The whole craft needs to orient itself to transmit: "The identical Voyager spacecraft are three-axis stabilized systems that use celestial or gyro referenced attitude control to maintain pointing of the high-gain antennas toward Earth."

The general DSN site is here; however, for detail on the system hardware, services, and capabilities, see the 810-5 Handbook.

The general DSN site is here; however, for detail on the system hardware, services, and capabilities, see the 810-5 Handbook.

Sometimes I wonder how much further ahead humanity would be if we built everything with the need to have it last decades before becoming nonfunctional, then I realize that with the rate technology has advanced, that is just not possible. Not to mention that we would have a totally different world economy if people weren't continually replacing perfectly functional items, from clothing to electronics to vehicles. So much of the global economy is dependent on people buying more things.

Only if you don't mind your next cell phone costing you a few months' salary. Top-notch quality in tech is costly:

The cost of the Voyager 1 and 2 missions -- including launch, mission operations from launch through the Neptune encounter and the spacecraft's nuclear batteries (provided by the Department of Energy) -- is $865 million.

(That'd be $3.2B in 2011 dollars)
http://voyager.jpl.nasa.gov/news/factsheet.html

The amazing thing (well, one of the amazing things) about the Voyager program is the communication link. Voyager's signal, as received on Earth, is almost unbelievably weak.

One can use the Friis Transmission Equation to see just how weak the signal from Voyager 1 is at the moment:

Pr = Pt * Gt * Gr * (lambda/(4 * pi * R))^2, where

Pr is received power, in watts;
Pt is transmitted power, in watts;
Gt is the gain of the transmitting antenna, relative to an isotropic source (a unit-less value);
Gr is the gain of the receiving antenna (one of the 70m DSN antennas), relative to an isotropic source (a unit-less value);
lambda is the operating wavelength, in meters, and equal to c/f, or very close to 300/fM, where fM is the operating frequency in MHz;
and R is the range (distance) in meters.

Pt = 18 watts (assuming this hasn't degraded over time and distance);
Gt = 48 dBi, or about 63100;
Gr = 74 dBi, or about 25.1*10^6;
fM = 8420 MHz, so lambda = 300/fM = 0.0356 meters; and
R = 17,545,000,000 km, or 1.75 * 10^13 meters.

Grinding all this out, one is left with a received signal strength -- at the terminals of a 70-meter dish, mind you -- of:

Pr = 18 * 63100 * 25.1*10^6 * (0.0356/(4 * pi * 1.75 * 10^13))^2 = 7.45 * 10^(-19) watts, or 745 -- wait for it -- zeptowatts.

This is equal to -181.3 dBW, or -151.3 dBm. (I don't know how many Libraries of Congress that is.)

In the year 2020, when the probe's power generator is expected to expire, the probe will be about 2 * 10^13 meters away from Earth; using the same calculation the signal will have weakened slightly, to 5.73 * 10^(-19) watts, or 573 zeptowatts, -182.4 dBW, or -152.4 dBm.

(Unless I've made some trivial calculation error, of course.)

The amazing thing (well, one of the amazing things) about the Voyager program is the communication link. Voyager's signal, as received on Earth, is almost unbelievably weak.

One can use the Friis Transmission Equation to see just how weak the signal from Voyager 1 is at the moment:

Pr = Pt * Gt * Gr * (lambda/(4 * pi * R))^2, where

Pr is received power, in watts;
Pt is transmitted power, in watts;
Gt is the gain of the transmitting antenna, relative to an isotropic source (a unit-less value);
Gr is the gain of the receiving antenna (one of the 70m DSN antennas), relative to an isotropic source (a unit-less value);
lambda is the operating wavelength, in meters, and equal to c/f, or very close to 300/fM, where fM is the operating frequency in MHz;
and R is the range (distance) in meters.

Pt = 18 watts (assuming this hasn't degraded over time and distance);
Gt = 48 dBi, or about 63100;
Gr = 74 dBi, or about 25.1*10^6;
fM = 8420 MHz, so lambda = 300/fM = 0.0356 meters; and
R = 17,545,000,000 km, or 1.75 * 10^13 meters.

Grinding all this out, one is left with a received signal strength -- at the terminals of a 70-meter dish, mind you -- of:

Pr = 18 * 63100 * 25.1*10^6 * (0.0356/(4 * pi * 1.75 * 10^13))^2 = 7.45 * 10^(-19) watts, or 745 -- wait for it -- zeptowatts.

This is equal to -181.3 dBW, or -151.3 dBm. (I don't know how many Libraries of Congress that is.)

In the year 2020, when the probe's power generator is expected to expire, the probe will be about 2 * 10^13 meters away from Earth; using the same calculation the signal will have weakened slightly, to 5.73 * 10^(-19) watts, or 573 zeptowatts, -182.4 dBW, or -152.4 dBm.

(Unless I've made some trivial calculation error, of course.)

The amazing thing (well, one of the amazing things) about the Voyager program is the communication link. Voyager's signal, as received on Earth, is almost unbelievably weak.

One can use the Friis Transmission Equation to see just how weak the signal from Voyager 1 is at the moment:

Pr = Pt * Gt * Gr * (lambda/(4 * pi * R))^2, where

Pr is received power, in watts;
Pt is transmitted power, in watts;
Gt is the gain of the transmitting antenna, relative to an isotropic source (a unit-less value);
Gr is the gain of the receiving antenna (one of the 70m DSN antennas), relative to an isotropic source (a unit-less value);
lambda is the operating wavelength, in meters, and equal to c/f, or very close to 300/fM, where fM is the operating frequency in MHz;
and R is the range (distance) in meters.

Pt = 18 watts (assuming this hasn't degraded over time and distance);
Gt = 48 dBi, or about 63100;
Gr = 74 dBi, or about 25.1*10^6;
fM = 8420 MHz, so lambda = 300/fM = 0.0356 meters; and
R = 17,545,000,000 km, or 1.75 * 10^13 meters.

Grinding all this out, one is left with a received signal strength -- at the terminals of a 70-meter dish, mind you -- of:

Pr = 18 * 63100 * 25.1*10^6 * (0.0356/(4 * pi * 1.75 * 10^13))^2 = 7.45 * 10^(-19) watts, or 745 -- wait for it -- zeptowatts.

This is equal to -181.3 dBW, or -151.3 dBm. (I don't know how many Libraries of Congress that is.)

In the year 2020, when the probe's power generator is expected to expire, the probe will be about 2 * 10^13 meters away from Earth; using the same calculation the signal will have weakened slightly, to 5.73 * 10^(-19) watts, or 573 zeptowatts, -182.4 dBW, or -152.4 dBm.

(Unless I've made some trivial calculation error, of course.)

The amazing thing (well, one of the amazing things) about the Voyager program is the communication link. Voyager's signal, as received on Earth, is almost unbelievably weak.

One can use the Friis Transmission Equation to see just how weak the signal from Voyager 1 is at the moment:

Pr = Pt * Gt * Gr * (lambda/(4 * pi * R))^2, where

Pr is received power, in watts;
Pt is transmitted power, in watts;
Gt is the gain of the transmitting antenna, relative to an isotropic source (a unit-less value);
Gr is the gain of the receiving antenna (one of the 70m DSN antennas), relative to an isotropic source (a unit-less value);
lambda is the operating wavelength, in meters, and equal to c/f, or very close to 300/fM, where fM is the operating frequency in MHz;
and R is the range (distance) in meters.

Pt = 18 watts (assuming this hasn't degraded over time and distance);
Gt = 48 dBi, or about 63100;
Gr = 74 dBi, or about 25.1*10^6;
fM = 8420 MHz, so lambda = 300/fM = 0.0356 meters; and
R = 17,545,000,000 km, or 1.75 * 10^13 meters.

Grinding all this out, one is left with a received signal strength -- at the terminals of a 70-meter dish, mind you -- of:

Pr = 18 * 63100 * 25.1*10^6 * (0.0356/(4 * pi * 1.75 * 10^13))^2 = 7.45 * 10^(-19) watts, or 745 -- wait for it -- zeptowatts.

This is equal to -181.3 dBW, or -151.3 dBm. (I don't know how many Libraries of Congress that is.)

In the year 2020, when the probe's power generator is expected to expire, the probe will be about 2 * 10^13 meters away from Earth; using the same calculation the signal will have weakened slightly, to 5.73 * 10^(-19) watts, or 573 zeptowatts, -182.4 dBW, or -152.4 dBm.

(Unless I've made some trivial calculation error, of course.)

The amazing thing (well, one of the amazing things) about the Voyager program is the communication link. Voyager's signal, as received on Earth, is almost unbelievably weak.

One can use the Friis Transmission Equation to see just how weak the signal from Voyager 1 is at the moment:

Pr = Pt * Gt * Gr * (lambda/(4 * pi * R))^2, where

Pr is received power, in watts;
Pt is transmitted power, in watts;
Gt is the gain of the transmitting antenna, relative to an isotropic source (a unit-less value);
Gr is the gain of the receiving antenna (one of the 70m DSN antennas), relative to an isotropic source (a unit-less value);
lambda is the operating wavelength, in meters, and equal to c/f, or very close to 300/fM, where fM is the operating frequency in MHz;
and R is the range (distance) in meters.

Pt = 18 watts (assuming this hasn't degraded over time and distance);
Gt = 48 dBi, or about 63100;
Gr = 74 dBi, or about 25.1*10^6;
fM = 8420 MHz, so lambda = 300/fM = 0.0356 meters; and
R = 17,545,000,000 km, or 1.75 * 10^13 meters.

Grinding all this out, one is left with a received signal strength -- at the terminals of a 70-meter dish, mind you -- of:

Pr = 18 * 63100 * 25.1*10^6 * (0.0356/(4 * pi * 1.75 * 10^13))^2 = 7.45 * 10^(-19) watts, or 745 -- wait for it -- zeptowatts.

This is equal to -181.3 dBW, or -151.3 dBm. (I don't know how many Libraries of Congress that is.)

In the year 2020, when the probe's power generator is expected to expire, the probe will be about 2 * 10^13 meters away from Earth; using the same calculation the signal will have weakened slightly, to 5.73 * 10^(-19) watts, or 573 zeptowatts, -182.4 dBW, or -152.4 dBm.

(Unless I've made some trivial calculation error, of course.)