How Much Solar Energy Can Be Received From Moonshine?

How much solar energy does the moon receive?

Physicist Wants To Beam Solar Energy Back From Moon’s Surface The Apollo 14 lunar module in the glare of a blazing Sun. Credit: NASA Credit: NASA Infalling solar radiation constantly illuminates the Moon’s surface with the equivalent of some 13,000 terawatts of solar power.

1. So, why not take a chunk of that energy and develop it into lunar-based solar power (LSP)? The idea would be to manufacture and deploy lunar solar power collecting stations that would concentrate and convert a portion of that Sunlight into electricity for wireless transmission back to Earth.
2. Far-fetched? Admittedly, it’s an idea that’s slightly ahead of its time, but for four decades now, retired University of Houston physicist David Criswell has been championing the notion of using several hundred square kilometers-worth of solar panels to collect infalling sunlight on the Moon as a sustainable source of clean electricity.

“By the year 2050, ten billion people will require at least 2 kilowatts of electricity per person or a global total of 20 terawatts,” Criswell told me. This, he says, is nearly 70 times more energy output than what was projected from original concepts of space-based solar power from Earth orbit.

• And unlike Earth orbit, Criswell contends that the lunar surface contains all the materials needed to build an LSP project’s retinue of solar cells, electric collecting wires, microwave generation and transmission equipment, microwave antennas, as well as most support equipment and supplies.
• A lunar-based solar power system (LSP) could quickly be demonstrated and grow quickly enough to soon power the whole of the U.S.

Criswell says. Such a system, Criswell says, would initially consist of ten 100 kilometer-wide circular collecting bases at the edges of the lunar nearside. The bases would be filled with billboard-sized microwave reflectors that from Earth, says Criswell, would appear to overlap.

“Each base would output hundreds of separate beams directed toward Earth receivers or via redirectors in a range of Earth orbits,” said Criswell. An individual beam could then be focused to Earth-based receiving antennas spanning a few hundred-meters in diameter, he says. Criswell’s own models of his proposed 20 terawatt LSP system provides an eventual projected wholesale price of 0.001 cents per kilowatt hours of electricity.

By comparison, an average American household pays in the range of 12 cents per kilowatt hour. * So, LSP ultimately would offer consumers totally clean energy at great savings. Even so, LSP is not without its critics. “A power station on the Moon would deliver roughly 200 gigawatts to a single location on Earth,” John Mankins, President of Mankins Space Technology, Inc., told me.

There are no markets that need that amount of power in a single large “chunk.” However, no matter where such beamed power were to land on Earth, it could still be readily redistributed when and where as needed. And Spacefaring Institute President Mike Snead told me that eventually the Earth-Moon system will be ‘electrified.’ That is, so that transmitted electromagnetic radiation in microwave, terahertz, and laser wavelengths will distribute electrical power.

“Eventually, this will extend into the central solar system,” said Snead. “As part of this electrification, there may be some benefit in providing transmitted electrical power from the lunar surface.” He foresees “beamed power” replacing chemical propulsion with various forms of electric-thermal propulsion.

For his part, Criswell remains undaunted and says that within ten years at a cost of $240 billion (in 1990 U.S. dollars), a LSP base could be built that would generate 0.1 terawatts of electric power for delivery back to Earth. Such a project, he says, would offer investors a projected eventual return of $440 billion in gross revenue and a profit of some $200 billion.

Then within 30 to 40 years, Criswell says Criswell applauds the new commercial space race between SpaceX and Blue Origins which he says is generating interest in lunar project development. And he’s hopeful that such development will eventually lead to lunar-based solar power.

I really think the Moon is our only option for sustainable and affordable electric power on a global scale,” said Criswell. * Correction: This post has been updated to note that the average American household pays roughly 12 cents per kilowatt hour for electricity, not 0.12 cents per kilowatt hour. *A very recent previous dealt with space-based solar power from Earth orbit.

: Physicist Wants To Beam Solar Energy Back From Moon’s Surface

Is it possible to get solar energy from the moon?

We’ll say yes; the moon also supplies solar energy. However, it’s barely strong enough to satisfy the photovoltaic cells, which are embedded components that convert energy into electricity. Lunar radiation is essentially a reflection of the sunlight since the moon lacks a light source.

Can moonlight produce electricity?

Can Moon Light Produce Electricity From Solar Panels ? The answer is a definite YES, because Moonlight is nothing but reflected Sunlight. Solar pv panels do convert moonlight to electricity. It can be used to power PV cells at a cost of 345:1, meaning, a panel that would normally produce 3450 W at high noon would produce only 10 W of power during the full moon.

• The quarter moon (50% illumination) would likewise produce only 5 W, and so forth.
• Concentrating moonlight using reflective or refractive techniques would enhance the wattage.
• As long as the light has a wavelength within 400-1127 nm (violet to near-infrared), the PV cell will convert it to electricity.

It doesn’t matter if it is sunlight, moonlight or flashlight. With a full moon on a cloudless night, you get about 1/350,000 th as much as at full noon sun. So your 7,000 watt solar roof might output 20 milliwatts at full moon. Your inverter might cut out at such low powers, so you might get nothing from your system, but the solar panels are producing.

1. A solar panel that’s rated at 50 watts produced enough current to light up a red LED (I have tried it).
2. Looking at present technology, I would say that it is not possible to generate usable electricity from solar panel.
3. Present solar panel needs energy of 1.1 eV (equal to band-gap of Silicon) to create electron-hole pair which moon light cannot provide due to less intensity(less energy).

If in future, we are able to replace Silicon with a material whose band-gap is equal to energy provided by moon light then solar panel(or I should say Lunar panel) can be used at night for electricity generation.This will also solve the problem of battery requirement for storage.

How much solar energy can I produce?

Most solar panels for homes generate around 250 – 400 watts but for larger homes, can produce up to 750 – 850 per kilowatt hour annually. Solar panel manufacturers determine the solar power output for products based on zero obstructions.

Does the Moon ever get 100%?

Copyright Antonio Cidadao, Used by permission. Click on picture to see large version. From any location on the Earth, the Moon appears to be a circular disk which, at any specific time, is illuminated to some degree by direct sunlight. Like the Earth, the Moon is a sphere which is always half illuminated by the Sun, but as the Moon orbits the Earth we get to see more or less of the illuminated half.

During each lunar orbit (a lunar month), we see the Moon’s appearance change from not visibly illuminated through partially illuminated to fully illuminated, then back through partially illuminated to not illuminated again. Although this cycle is a continuous process, there are eight distinct, traditionally recognized stages, called phases.

The phases designate both the degree to which the Moon is illuminated and the geometric appearance of the illuminated part. These phases of the Moon, in the sequence of their occurrence (starting from New Moon), are listed below. New Moon – The Moon’s unilluminated side is facing the Earth. The Moon is not visible (except during a solar eclipse). Waxing Crescent – The Moon appears to be partly but less than one-half illuminated by direct sunlight. The fraction of the Moon’s disk that is illuminated is increasing. First Quarter – One-half of the Moon appears to be illuminated by direct sunlight. The fraction of the Moon’s disk that is illuminated is increasing. Waxing Gibbous – The Moon appears to be more than one-half but not fully illuminated by direct sunlight. The fraction of the Moon’s disk that is illuminated is increasing. Full Moon – The Moon’s illuminated side is facing the Earth. The Moon appears to be completely illuminated by direct sunlight. Waning Gibbous – The Moon appears to be more than one-half but not fully illuminated by direct sunlight. The fraction of the Moon’s disk that is illuminated is decreasing. Last Quarter – One-half of the Moon appears to be illuminated by direct sunlight. The fraction of the Moon’s disk that is illuminated is decreasing. Waning Crescent – The Moon appears to be partly but less than one-half illuminated by direct sunlight. The fraction of the Moon’s disk that is illuminated is decreasing. Following waning crescent is New Moon, beginning a repetition of the complete phase cycle of 29.5 days average duration.

The time in days counted from the time of New Moon is called the Moon’s “age”. Each complete cycle of phases is called a “lunation”. Because the cycle of the phases is shorter than most calendar months, the phase of the Moon at the very beginning of the month usually repeats at the very end of the month.

When there are two Full Moons in a month (which occurs, on average, every 2.7 years), the second one is called a “Blue Moon”. See the article “Once in a Blue Moon” for the story of how the usage of this term has evolved (Ref: Philip Hiscock, Sky & Telescope, March 1999, pp.52-55.).

The first time that the thin waxing crescent Moon is visible after New Moon (low in the evening sky just after sunset) marks the beginning of a month in the Islamic Calendar – see the Astronomical Information Center for Crescent Moon Visibility and the Islamic Calendar, Although Full Moon occurs each month at a specific date and time, the Moon’s disk may appear to be full for several nights in a row if it is clear.

This is because the percentage of the Moon’s disk that appears illuminated changes very slowly around the time of Full Moon (also around New Moon, but the Moon is not visible at all then). The Moon may appear 100% illuminated only on the night closest to the time of exact Full Moon, but on the night before and night after will appear 97-99% illuminated; most people would not notice the difference.

Even two days from Full Moon the Moon’s disk is 93-97% illuminated. New Moon, First Quarter, Full Moon, and Last Quarter phases are considered to be primary phases and their dates and times are published in almanacs and on calendars. (Click here for a list.) The two crescent and two gibbous phases are intermediate phases, each of which lasts for about a week between the primary phases, during which time the exact fraction of the Moon’s disk that is illuminated gradually changes.

The phases of the Moon are related to (actually, caused by) the relative positions of the Moon and Sun in the sky. For example, New Moon occurs when the Sun and Moon are quite close together in the sky. Full Moon occurs when the Sun and Moon are at nearly opposite positions in the sky – which is why a Full Moon rises about the time of sunset, and sets about the time of sunrise, for most places on Earth.

First and Last Quarters occur when the Sun and Moon are about 90 degrees apart in the sky. In fact, the two “half Moon” phases are called First Quarter and Last Quarter because they occur when the Moon is, respectively, one- and three-quarters of the way around the sky (i.e., along its orbit) from New Moon.

The relationship of the Moon’s phase to its angular distance in the sky from the Sun allows us to establish very exact definitions of when the primary phases occur, independent of how they appear. Technically, the phases New Moon, First Quarter, Full Moon, and Last Quarter are defined to occur when the excess of the apparent ecliptic (celestial) longitude of the Moon over that of the Sun is 0, 90, 180, and 270 degrees, respectively.

1. These definitions are used when the dates and times of the phases are computed for almanacs, calendars, etc.
2. Because the difference between the ecliptic longitudes of the Moon and Sun is a monotonically and rapidly increasing quantity, the dates and times of the phases of the Moon computed this way are instantaneous and well defined.

The percent of the Moon’s surface illuminated is a more refined, quantitative description of the Moon’s appearance than is the phase. Considering the Moon as a circular disk, the ratio of the area illuminated by direct sunlight to its total area is the fraction of the Moon’s surface illuminated; multiplied by 100, it is the percent illuminated.

At New Moon the percent illuminated is 0; at First and Last Quarters it is 50%; and at Full Moon it is 100%. During the crescent phases the percent illuminated is between 0 and 50% and during gibbous phases it is between 50% and 100%. For practical purposes, phases of the Moon and the percent of the Moon illuminated are independent of the location on the Earth from where the Moon is observed.

That is, all the phases occur at the same time regardless of the observer’s position.

How much fuel does it take to get to the Moon?

The new age space race is upon us as Elon Musk’s SpaceX gears up to send billionaires to the moon and NASA plans for upcoming missions this month at Kennedy Space Center and Cape Canaveral Air Force Station. So naturally, inquiring minds want to know: just how much fuel does it take to get to the moon? Next Sunday, August 13 a SpaceX Falcon 9 rocket will blast off from Kennedy Space Center aimed for NASA’s International Space Station.

The Dragon spacecraft is an unmanned capsule that will fly with 3 tonnes of supplies, small potatoes next to their ambitious goal of sending two space tourists to the moon in 2018, their first mission with humans on board the spacecraft. The cost for a single load of fuel for the SpaceX Dragon spacecraft, presumably a more austere model than the one that will be used for space tourism in the near future, is between $200,000 and $300,000,

Makes you think twice about complaining about how much is costs to fill your Range Rover! Now for a bit of history: for the 1967 Apollo mission to the moon, Saturn V rocket ‘s first stage carried 203,400 gallons of kerosene fuel and 318,000 gallons of liquid oxygen needed for, totaling over 500,000 gallons of fuel for getting out of the atmosphere alone.

The second stage carried another 260,000 gallons of liquid hydrogen and 80,000 gallons of liquid oxygen. The third stage carries 66,700 gallons of liquid hydrogen and 19,359 gallons of liquid oxygen. All told, the rocket that achieved one small step for a man and one giant leap for mankind held just under 950,000 gallons of fuel.

Since then, space-age technologies have come a long way. By comparison, SpaceX’s Falcon 9 uses just a mere fraction of the fuel combusted by Saturn V. To be fair, the Falcon 9 is smaller, simpler, and not designed to re-enter orbit safely (it has no stage three), but even so, you can see that the fuel efficiency of spacecrafts has improved leaps and bounds.

• SpaceX fuels their crafts not with liquid hydrogen, but with kerosene, which has a lot more energy per gallon,
• Thanks to this and other advances, Falcon 9’s first stage uses 39,000 gallons of liquid oxygen and almost 25,000 gallons of kerosene, while the second stage uses 7,300 gallons of liquid oxygen and 4,600 gallons of kerosene.

Combined, it makes lean mean 75,900 gallons of fuel. As we speak, SpaceX is finishing their plans for a heavy-lift launch vehicle known as Falcon Heavy, which is scheduled to fly for the first time this summer. Other big names in the private space industry are working on similar heavy-duty model that will be able to bring unprecedented amounts of supplies into space.

1. The United Launch Alliance’s Vulcan is scheduled to launch in 2019 and Blue Origin is currently working on a model called the New Glenn, which will allegedly be able to deliver 100,000 pounds of cargo (or space tourists) to lower Earth orbit.
2. NASA is also trying to compete with privatized space exploration companies, developing their own giant rocket known as the Space Launch System, which they claim to be the most powerful rocket ever created.

While the look and size are quite similar to the now-antique Saturn V, this rocket will have a capacity of 150,000 and 290,000 pounds. While this dwarfs the models being created by the private space industry, critics point out that due to its size and weight the Space Launch System is extremely expensive (around $1 billion per mission ) and would just be launched once or twice a year, making it unable to compete with the ambitious launch schedules of companies like SpaceX.

1. Thanks to the introduction of privatized market competition in the space race, we’re now seeing more economic and fuel-efficient rockets than ever, and it seems that the rate of innovation will continue to accelerate at warp speed.
2. Perhaps in another 50 years, moon vacations won’t just be for billionaires.

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Can we pull moon to Earth?

Gravity – As a child, even we used to think it was some magic, but we hate to break it to you, that’s not magic, it’s science. This is relatively close to magic, and today, we are going to talk about how the moon is not attracted to Earth and how we are safe from getting hit by the moon anytime soon.

Why can’t we put solar panels on the moon?

There are several challenges. Solar cells can suffer damage and degradation by radiation exposure and the highly charged particles present on the Moon. And high daytime temperatures can soar to over 260˚ F, damaging the electronics of solar array systems.

Can moon produce its own light?

This activity can be used in conjunction with StarChild Solar System Level 2 information OBJECTIVES: 1. Identify the Earth-Moon relationship 2. Identify the phases of the Moon 3. Identify the Earth-Moon-Sun alignment that results in solar and lunar eclipses MATERIALS: • Lamp with at least a 60 watt bulb • Large orange • One volunteer Procedure: As Earth’s only natural satellite, the Moon has long been an object of fascination and confusion. Over the course of a 29-day cycle, the Moon shows us many different “faces”. These different “faces” are called phases and they are the result of the way the Sun lights the Moon’s surface as the Moon orbits Earth.

1. The Moon can only be seen as a result of the Sun’s light reflecting off it.
2. It does not produce any light of its own.
3. This demonstration will illustrate why the Moon has so many different looks within that 29-day period known as the lunar cycle.
4. Prior to or after the demonstration, allow the students to go on-line and read additional background information related to the Moon (Solar System section) and man’s exploration of this satellite (Space Stuff section).

The following demonstration can be useful to help the students visualize the situation.1. Put the lamp in the middle of the room. After the lamp has been turned on, darken all other lights. The lamp represents the Sun while the orange represents the Moon and the volunteer represents the Earth.

1. Only the volunteer can see the intended results of this demonstration, so each student will have to take their turn in order to understand the phases of the Moon.2.
2. Earth will face the Sun holding the Moon in the left hand.
3. The Moon should be held in front at arm’s length and slightly elevated overhead.

(Make sure the students understand that it is because of the Moon’s slightly inclined orbit around Earth that we usually see a full Moon when the Earth is between the Sun and Moon.) 3. Notice that the lamp has lit up the side of the Moon away from Earth.

No one on Earth can see the lit side at this point. This is a new Moon and it occurs when the Moon is between the Sun and Earth.4. While Earth is still facing toward the Sun, hold the left arm straight out to the side. People on Earth will now be able to see half of the Moon’s lit side. Because the Moon has now revolved one-quarter of the way around Earth, this phase is referred to as a first-quarter Moon.

A first-quarter Moon occurs approximately one week after a new Moon. Have the students carefully notice which half of the Moon is lit during a first-quarter Moon.5. For the next phase, Earth’s back should be to the Sun. The Moon should held out straight in front of Earth, still slightly elevated.

1. Earth can now see the full lit face of the Moon.
2. This phase is a full Moon.
3. The Moon has now completed half of its revolution around Earth.6.
4. Before moving Earth into the next position place the Moon in the right hand.
5. Now Earth should move the right arm into a position straight out to the side.
6. Once again only half of the Moon is lit.

Have the students carefully note which half is lit. This is the phase known as a third-quarter Moon. The Moon has now completed three-quarters of its revolution around Earth. This “face” appears approximately three weeks after a new Moon.7. To complete the demonstration, have Earth once again face the Sun.

• The Moon should be held straight out in front of Earth, again showing the darkened side facing Earth.
• The lunar cycle now starts over again.
• The demonstration has concluded.
• EXTENSIONS: (1) The intermediate phases of the Moon may also be illustrated with this demonstration.
• A waxing crescent will occur between a new Moon and a first-quarter Moon.

A waxing gibbous occurs between the first-quarter Moon and full Moon. A waning gibbous occurs between a full Moon and a third-quarter Moon. A waning crescent appears between a third-quarter Moon and a new Moon. (2) To illustrate a lunar eclipse while demonstrating the full Moon phases, allow the arm holding the Moon to drop so that the Moon is now in the Earth’s shadow.

• Lunar eclipses occur on an average of twice a year.
• 3) To illustrate a solar eclipse, allow the arm holding the Moon to drop while demonstrating a new Moon.
• A shadow should fall across a part of the Earth.
• Explain to the students that people living on the part of the Earth that is in the shadow will experience a solar eclipse.

Solar eclipses are less frequent than lunar eclipses. A solar eclipse occurs on an average of once every 18 months. (4) As a follow-up activity, the students may go on-line and complete Moonlight Madness in StarChild. This activity is located in Level 2 of the Solar System section.

Is moonlight enough for photosynthesis?

Plants cannot carry out photosynthesis in moonlight because it does not carry enough energy to excite chlorophyll molecule, i.e., reaction centres PS I and PS II, so light-dependent reactions does not get initiated. Thus, no photosynthesis occurs in presence of moonlight.

Is there any benefit to moonlight?

Some of the benefits of this ritual: –

Helpful on hypertension treatment.Migraines.Hives.Rashes.Urticaria.Inflammatory conditions.Increases fertility.Relieve stress and anxiety.Hormonally beneficial for women in particular.

Because moonlight actually reflects sunlight, it too can boost vitamin D levels, and provides us nitric oxide, which is known to help regulate blood flow and reduce blood pressure,

How strong is moonlight vs sunlight?

Strange Moonlight | Science Mission Directorate | | + Join mailing list Sept.28, 2006: Not so long ago, before electric lights, farmers relied on moonlight to harvest autumn crops. With everything ripening at once, there was too much work to to do to stop at sundown. A bright full moon—a “Harvest Moon”—allowed work to continue into the night. The moonlight was welcome, but as any farmer could tell you, it was strange stuff. How so? See for yourself. The Harvest Moon of 2006 rises on October 6th, and if you pay attention, you may notice a few puzzling things: 1. Moonlight steals color from whatever it touches.

Regard a rose. In full moonlight, the flower is brightly lit and even casts a shadow, but the red is gone, replaced by shades of gray. In fact, the whole landscape is that way. It’s a bit like seeing the world through an old black and white TV set. Right: The Harvest Moon of 2005. Photo credit: Sr. Fins Eirexas of Pobra do Caramiñal, Galiza, Spain.

“Moon gardens” turn this 1950s-quality of moonlight to advantage. White or silver flowers that bloom at night are both fragrant and vivid beneath a full moon. Favorites include Four-O’clocks, Moonflower Vines, Angel’s Trumpets—but seldom red roses.

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2. If you stare at the gray landscape long enough, it turns blue. The best place to see this effect, called the “blueshift” or “Purkinje shift” after the 19th century scientist Johannes Purkinje who first described it, is in the countryside far from artificial lights.

As your eyes become maximally dark adapted, the blue appears. Film producers often put a blue filter over the lens when filming night scenes to create a more natural feel, and artists add blue to paintings of nightscapes for the same reason. Yet if you look up at the full moon, it is certainly not blue.

(Note: Fine ash from volcanoes or forest fires can turn moons blue, but that’s another story.) 3. Moonlight won’t let you read. Open a book beneath the full moon. At first glance, the page seems bright enough. Yet when you try to make out the words, you can’t.

Moreover, if you stare too long at a word it might fade away. Moonlight not only blurs your vision but also makes a little blind spot. (Another note: As with all things human, there are exceptions. Some people have extra-sensitive cones or an extra helping of rods that do allow them to read in the brightest moonlight.) This is all very strange.

Moonlight, remember, is no more exotic than sunlight reflected from the dusty surface of the moon. The only difference is intensity: Moonlight is about 400,000 times fainter than direct sunlight. So what do we make of it all? The answer lies in the eye of the beholder. The human retina is responsible. The retina is like an organic digital camera with two kinds of pixels: rods and cones. Cones allow us to see colors (red roses) and fine details (words in a book), but they only work in bright light.

After sunset, the rods take over. Rods are marvelously sensitive (1000 times more so than cones) and are responsible for our night vision. According to some reports, rods can detect as little as a single photon of light! There’s only one drawback: rods are colorblind. Roses at night thus appear gray. If rods are so sensitive, why can’t we use them to read by moonlight? The problem is, rods are almost completely absent from a central patch of retina called the fovea, which the brain uses for reading.

The fovea is densely packed with cones, so we can read during the day. At night, however, the fovea becomes a blind spot. The remaining peripheral vision isn’t sharp enough to make out individual letters and words. Finally, we come to the blueshift. Consider this passage from a 2004 issue of the Journal of Vision : “It should be noted that the perception of blue color or any color for that matter in a purely moonlit environment is surprising, considering that the light intensity is below the detection threshold for cone cells.

Therefore if the cones are not being stimulated how do we perceive the blueness?” -“Modeling Blueshift in Moonlit Scenes using Rod-Cone Interaction” by Saad M. Khan and Sumanta N. Pattanaik, University of Central Florida. The authors of the study went on to propose a bio-electrical explanation-that signals from rods can spill into adjacent blue-sensitive cones under conditions of full-moon illumination (see the diagram, right).

This would create an illusion of blue. “Unfortunately,” they point out, “direct physiological evidence to support or negate the hypothesis is not yet available.” So there are still some mysteries in the moonlight. Look for them on Oct.6th under the Harvest Moon.

Caveat Lunar: This story makes some generalizations about what people can see at night but, as with all things human, there are exceptions: Some people can read by moonlight; others have no trouble seeing the red petals of a moonlit rose. These people have “moonvision,” boosted by an extra-helping of rods or unusually sensitive cones.

Are you one of them? Author: Dr. Tony Phillips | Editor: Dr. Tony Phillips | Credit: Science@NASA

More to the story.

More information about the Moonlight blueshift: The blueshift is sometimes attributed to the spectral response of rods. Although rods are nominally color blind, they do not respond equally to all colors: Rods are more sensitive to blue-green photons and less sensitive to red photons. You can see this in your moonlit rose. By day, the red flower dominates the green leaves. At night, the situation is reversed. The green leaves are more vivid than the red flower. No matter which part of the rose stands out most, however, the ensemble is still gray. This is because the rods have no mechanism for separating colors. Shades of gray are all we get. Cones are able to separate colors because they come in three varieties: red-sensitive, green-sensitive, and blue-sensitive. The brain can sort out the color of an object by noting which kind of cone it stimulates most. Rods, on the other hand, come in one variety only-monochromatic, which brings us back to the mystery of the blue shift. If rods can’t separate colors, how does the brain register a blue rather than gray landscape? Khan and Pattanaik’s hypothesis of rod signals “bleeding” into adjacent blue-sensitive cones provides a possible but untested explanation. Dates and Times: The Moon is full on Oct 7th at 0313 UT or 11:13 pm EDT on Oct.6th: Moon phase calendar. Web Links: The Eye and Night Vision – from the USAF Special Report, AL-SR-1992-0002, “Night Vision Manual for the Flight Surgeon”, written by Robert E. Webvision – The organization of the Retina and the Visual SystemThe Purkinje shift – (Wikipedia)Rods and Cones – (Hyperphysics)Night Rendering – a study of moonlight in art and computer graphicsWhat do dogs see? – (Journal of Veterinary Medicine)How Vision Works – (HowStuffWorks)The Vision for Space Exploration

Strange Moonlight | Science Mission Directorate

How much does a 7.5 kW solar system produce?

How much do I save? – Finally, let’s find out how much you can save per month on average from your monthly electric bill! Let’s plug it all in: On average, your solar system is going to lose some energy due to wiring, power, inverter efficiency, so you actually end up using 80% of your solar system’s capacity.

• To figure out how many kilowatt-hours (kWh) your solar panel system puts out per year, you need to multiply the size of your system in kW DC times the,8 derate factor times the number of hours of sun.
• So if you have a 7.5 kW DC system working an average of 5 hours per day, 365 days a year, it’ll result in 10,950 kWh in a year.

If you divide your expected 10,950 kWh of annual production by 12, you’ll see that your system will offset about 912 kWh per month from your monthly electric bill, which can translate to $100 or more ( in California this would save you about $250) per month depending on how much you pay per kWh ! So to break this down into simple math that you can do: AC rating = Average kWh per month / 30 days / average sun hours per day example: 903 kWh per month / 30 days / 5 hours = 6.02 kW AC DC rating = AC rating / derate factor (.8 is conservative, but a range would be,8 –,85) example: 6.02 kW AC /,8 = 7.53 kW DC Number of panels = DC rating / Panel Rating (e.g.25o W) *note this is important b/c panels are rated in watts, and the systems are rated in kilowatts (1000 watts).

1. So a 7.53 kW system = 7530 Watts and a 250 watt panel =,250 kW example: 7.53 kW x 1000 / 250 watt = 30.12 panels, so roughly 30 250 panels (30 x 250W = 7500 Watts = 7.5 kW) NOTE: to get your average usage, preferably add up your last 12 months usage and divide by 12.
2. In a pinch, the last 6 months can be a close approximation, but a year’s worth of data is far better.

Have you calculated how much your solar system will produce? Tell us in the comments! More:

Find Out If Solar Panels Are Right for Your House Best Solar Panel Kits How much do solar panels save?

Image Credit: via FlickR under a Creative Commons license, By NREL, via Wikimedia Commons

How many solar panels do I need for 1000 kWh per month?

4. Number of Solar Panels Needed for 1000 kWh – Let’s start plugging our numbers into the equation above. First, we can divide our monthly electric usage (1000 kWh) by our monthly peak sun hours (120). That gives us 8.333 kW. To convert kilowatts to watts — the unit of power supplied on most solar panel ratings — we’ll multiply by 1000, giving us 8333 watts.

How big is a 400w solar panel?

A typical 400 W solar panel is about 75 x 45 inches in dimensions, which is about 25 square feet. A 6 kW system will need about 15 solar panels rated 400 W.

How old is 1,000 moons?

Sahasra purna chandrodayam Sahasra Purna Chandrodayam (or Sahasra Chandra Darshan) is the celebration of a person’s 1000th during his or her life as a special occasion. This is a Hindu custom in India. The time between similar lunar phases, the, is on average 29.53 days, and thus 1000 moons equals 29530 days = 80.849 years = approximately 80 years, 10 months on the Western calendar.

In practice the celebration traditionally is held 3 full moons before a person’s 81st Birthday. This ritual is also known as Sahasra Chandra Darshan (सहस्र-(पूर्ण)चन्द्र-दर्शन) or Chandra Ratharohan The ritual is to provide mental and physical strength in his/her old age and to encourage him/her to pursue spiritual liberation from all problems in this life.

In sahasra means 1000, purna means full, and chandrodayam means dawn of moon. A similar kind of celebrations for elderly persons are

• Completion of 60 years – (or Shashti poorthi )
• Completion of 77 years, 7 months, 7 days – Bhim Rathaarohan or Bhima Ratha Shanthi
• Completion of 88 years 8 months, 8 days – Deva Rathaarohan or Deva Ratha Shanthi
• Completion of 99 years, 9 months, 9 days – Divya Rathaarohan or Divya Ratha Shanthi
• Completion of 105 years 8 months, 8 days – Mahadivya Rathaarohan or Mahadivya Ratha Shanthi

What year will have 13 full moons?

A supermoon phenomenon happens when the moon moves at its closest point to Earth, which is also known as perigee. Due to this, the moon appears slightly bigger than a normal full moon. – Agencies Representative Image It will be a sheer treat for sky watchers in 2023, as there will be 13 full moons, 4 of which will be supermoons, and 1 blue moon, Moreover, there will be a partial solar eclipse this year, but that can be seen only in the eastern United States,

A supermoon phenomenon happens when the moon moves at its closest point to Earth, which is also known as perigee. Due to this, the moon appears slightly bigger than a normal full moon. Though a supermoon looks better than a full moon, it’s not easy to notice the difference. Besides supermoons, there will be a blue moon event in August this year, which will be the second full moon in a month.

List of the full moons for the year, along with their nicknames:

Jan.6 — wolf moon.Feb.5 snow moon.March 7 — worm moon.April 6 — pink moon.May 5 — flower moon,June 3 — strawberry moon.July 3 — buck moon also a supermoon.Aug 1 — sturgeon moon also a supermoon.Aug.30 — blue moon also a supermoon.Sept.29 — harvest moon also a supermoon.Oct.28 — hunter’s moon.Nov.27 — beaver moon.Dec.26 — cold moon.

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How many years is 200 moons?

Premiering Wednesday on Disney+, whose corporate parent conveniently acquired the property in its ingestion of Lucasfilm, “Willow” is a series-long sequel to the 1988 fantasy film in which an aspiring sorcerer (Warwick Davis in the title role) from a race of little people sets off to deliver a human baby, found like Moses in the bulrushes, into responsible large-people care.

• There are a lot of opinions among genre fans as to how best to execute such stories, but the series is fantasy as I like it best — funny, fun and just a little frightening, sometimes serious but never self-serious.
• If my year-end favorites piece were not already filed, “Willow” would have been a contender.

It has been 34 years since the film was released, though in the timeline of the series, “200 moons” have passed, or 16.66666 years, according to my calculator. Which makes all the younger characters teenagers, including Elora Danan, the baby whose safety is the main business of the movie and whose grown-up identity, hidden even from herself, is revealed at the end of the series’s first episode.

Every time her name was spoken, I pictured Devery Jacobs, who plays someone with the same name on ” Reservation Dogs ” — distracting, perhaps, but also pleasant.) As to returning players Davis and Joanne Whalley, as Sorsha — daughter of the movie’s evil sorceress/queen and now a queen herself — time has been kind to them.

Val Kilmer’s Madmartigan, the rogue-turned-hero Han Solo of the piece — who, we learn from opening narration, later married Sorsha and is the father of her teenage twins, Kit (Ruby Cruz) and Airk (Dempsey Bryk) — left a decade earlier in search of a magic breastplate and never returned.

1. But he’s still very much a presence.
2. It and Airk are unconventional royals, not keen on what their station has in store for them.
3. Airk, a bit of a rapscallion, is enamored of Dove, who works in the bakery; Kit, who dreams of life beyond the horizon, is betrothed for political reasons to Graydon (Tony Revolori), a nerdish prince from a neighboring kingdom, but would rather be crossing swords with Jade (Erin Kellyman), her best friend and sparring partner, who is set to become the kingdom’s first female knight.

Before the wedding can take place, however, a mystic fog full of monsters descends upon the palace, and Airk is kidnapped. A quest is organized, in which our young heroes, including Grayson (smart kids come in handy), set off to find him. They are accompanied by a couple of adult chaperons — notably Boorman (Amar Chadha-Patel), a thief sprung from the dungeon, who has history with Sorsha and Madmartigan and knows the territory outside “the barrier,” a magical force field protecting the peaceable kingdoms from the less peaceable.

As in most any sequel to an adventure that ends happily, a new evil is rising, or an old evil is rising again, and both Sorsha and Willow can feel it coming. Because every fellowship needs a sorcerer, the party is sent to find Willow, who has gained stature in his community but nevertheless feels something of a fraud— the move by which he defeated the film’s villainess was not magickal magic but ordinary prestidigitation.

He may not be much of a wizard — he is something of a wizard — but cleverness is more attractive than just waving a wand. The series was developed by Jonathan Kasdan (son of writer-director Lawrence, younger brother of director Jake), who, born in 1979, would be just the age to have had “Willow” strongly imprinted on his brain.

(In the greater web of show business “coincidence,” Kasdan co-wrote with his father the 2018 “Solo: A Star Wars Story,” which was directed by the original “Willow” director Ron Howard.) Kasdan’s initiation into screenwriting was on “Freaks & Geeks,” and he’s wrapped the swords and sorcery in “Willow” around a teen dramedy, with characters just starting to figure out their lives and their love lives — and who will make mistakes in either case, keeping things open for further seasons.

(“So you’re saying saving the world and having a relationship are mutually exclusive?” one will ask.) IP gonna IP, but, cult status aside, “Willow” is perhaps not the first, or second, or third property one would have expected to see revived, so expensively and at such length.

Leaving out the question of whether the show is “better” than the movie — its story by George Lucas, seemingly written with a dog-eared copy of “The Hero With a Thousand Faces” open at his elbow — the series goes to more, and more interesting, places, with fuller characterizations, less predictable plot lines and sharper jokes.

The movie was vaguely humorous, but the series is legitimately a comedy between, and often during, the scenes of suspense and violence. Temperamentally, it’s more ” Princess Bride ” than “Lord of the Rings,” with a hint of Monty Python in the way it sets modern dialogue and attitudes against a medieval backdrop, with lines like “You’re not the boss of me, princess” and “I’ve got to say, I’m feeling really energized and optimistic about this exorcism” and “I’m using my mind to remove that stick from your butt.” The series plays off of genre conventions without parodying them; it’s a self-aware celebration of the form.

That is to say, there are things you will have seen before, in new clothes. When a good guy is stabbed by a bad guy with a black magic staff, it’s immediately understood that possession is in his future. (You are not meant to be surprised when it arrives, but rather to wait for what you know is coming.) Elora Danan is the latest in a long line of prophesied Chosen Ones who must learn to use the force within her.

And as in fantastical journeys from “The Odyssey” to “The Wizard of Oz” and beyond, “Willow” offers a tour of various landscapes and cultures, taking our questers through the Wildwood, across the Shattered Sea to the Immemorial City, from the seven levels of the Candy Cane Forest — no, wait, that’s ” Elf.

• The show is big, in a casual sort of way; there are some major set pieces, including what struck me as a nod to “Indiana Jones” flicks — Kasdan’s father co-wrote “Raiders of the Lost Ark” — but it doesn’t overwhelm human affairs with Gondorian grandeur or mystic hoo-ha.
• Focus is kept on a handful of characters, who do lose track of each other now and again, or break off into smaller groups for intimate conversation, but (the kidnapped Airk excepted) they are never out of one another’s sight for long.

And Elora Danan’s isn’t the only mystery here; each harbors some sort of secret — in one scene, some of the team are dosed with a sort of truth-serum party drug, and a lot of information comes out — and more than one unsuspected relationship will be revealed.

1. As in the film, Davis is paramount, and he’s in a more complex role now, a mentor who still has a thing or two to learn, a grown-up herding teens twice his size.
2. The actor was 18 in his first real part, when the movie was released — he’d played an Ewok previously — and, like his character, has developed since; his comic chops are especially well-honed.

Whalley gets to do more substantial work in 10 minutes of the series than in the whole of the film. Chadha-Patel is ambiguously charming as a scalawag not entirely out for himself. The younger characters are lively and appealing, not the least because they can be a little impertinent; as much as they might seem forged according to type, the actors make them into individuals.

How much does 1 trip to the moon cost?

Naming a star, a crater, or even a planet after a loved one seems pretty romantic. After all, what makes a better gift that a rocky barren ditch that might one day trip up a future Mars rover ? Or a star that could one day be consumed by a hungry black hole ? So fleeting.

Yet so popular. So let’s take this idea of off-world gifts and really, really run with it. Why buy a chunk of a Moon rock when you could us e that excessive expendable income to add to the extremely short list of human beings who have actually journeyed to the Moon? You’ve got a few options when it comes to gifting a ticket to the Moon.

First, you could go with SpaceX, Last year, Elon Musk announced two private citizens will be flying around the Moon in a SpaceX rocket. More recently, he unveiled more details about one of the passengers: Yusaku Maezawa, a Japanese billionaire entrepreneur and art collector.

1. While neither Musk nor Maezawa would reveal the actual cost of the trip, Maezawa reportedly already paid a “significant deposit.” In addition, Musk did hint that a roundtrip ticket would likely cost the same as a visit to the ISS.
2. A 10-day trip will run you about $55 million, according to Axiom Space.

However, by many accounts this number can vary. NASA pays Roscosmos just above $81 million for a round-trip to the Soyuz capsule, according to The Verge, Alternatively, there’s Space Adventures, a company that charges around $150 million per seat for a trip around the Moon.

1. During the journey, customers will see the far side of the Moon lit up, and watch an Earth rise, all from the comfort of a Russia spacecraft.
2. This price includes 10 days docked on the ISS, acclimating to the new environment.
3. Other perks included in the cost are training, and a personal cosmonaut guide.

While the cost might sound steep, think of the lunar tourism opportunities! You can take check out the site of the first human landing – AKA Tranquility Base, see Buzz Aldrin’s foot print, U.S. flags, or even the golf balls astronaut Alan Shepard hit during an Apollo 14 moonwalk.

How much does it cost for NASA to go to the moon?

NASA’s Artemis moon rocket, slated to touch space for the very first time in 2022, was supposed to launch in 2017. It was supposed to encompass four missions, each with a price tag estimated a decade ago at $500 million – but a 2021 audit now projects a cost of $4.1 billion per launch.

What is moon dust made of?

The bulk chemical composition of lunar dust varies across the lunar surface, but is about 50% SiO2, 15% Al2O3, 10% CaO, 10% MgO, 5% TiO2 and 5-15% iron (Table 1), with lesser amounts of sodium, potassium, chromium, zirconium.

Does moon get as much sunlight as Earth?

Category: Space Published: August 6, 2015 The moon is actually quite dim, compared to other astronomical bodies. The moon only seems bright in the night sky because it is so close to the earth and because the trees, houses, and fields around you are so dark at night. Photo of the moon and earth when illuminated directly by sunlight, as taken by the DSCOVER spacecraft on July 16, 2015. Public Domain Image, source: NASA/NOAA. In general, we can see objects because they direct light into our eyes (or into cameras which record information that is later used by display screens to direct light into our eyes).

• There are two main ways that an object can direct light into our eyes.
• Either the object creates new light or it reflects light that already existed.
• Objects that create light tend to also reflect ambient light, so that they tend to be the brightest objects around.
• Examples include campfires, light bulbs, candle flames, and computer screens.

In terms of astronomical bodies, stars are the main objects that create significant amounts of visible light, and therefore are some of the brightest objects in the universe. In contrast, planets and moons do not generate their own visible light*. If a planet somehow became large enough to initiate nuclear fusion and begin glowing, it would no longer be a planet.

1. It would be a star.
2. Since planets and moons do not emit light, the only reason we can see them is because they reflect light from some other source.
3. The strongest source of light in our solar system is the sun, so usually we see planets and moons because they are reflecting sunlight.
4. The amount of sunlight incident on a moon or planet that gets reflected depends on the materials in its surface and atmosphere as well as its surface roughness.

Snow, rough ice, and clouds are highly reflective. Most types of rock are not. Therefore, a planet that is covered with clouds, such as Earth or Venus, is generally brighter than a rocky moon or planet that has no atmosphere. There are two main types of reflectivity: specular reflectivity and diffuse reflectivity.

1. Specular reflectivity measures how much of the incoming light gets reflected by the object in the direction given by the mirror angle.
2. In contrast, diffuse reflectivity measures how much light gets reflected in all directions.
3. A mirror has high specular reflectivity and low diffuse reflectivity.
4. In contrast, sand has low specular reflectivity and high diffuse reflectivity.

In everyday life, we experience specular reflectivity as the perception of mirror images and glare spots on the surface of objects. We experience diffuse reflectivity as a somewhat uniform brightness and color that exists on the surface of the object and is roughly the same no matter what our viewing angle is.

1. Many objects display significant amounts of both specular reflectivity and diffuse reflectivity.
2. For instance, a red polished sports car looks red from all angles because of its diffuse reflectivity, while at the same time displays bright spots of glare because of its specular reflectivity.
3. In general, roughening a surface tends to increase its diffuse reflectivity and decrease its specular reflectivity.

This is true because a rough surface has many little reflecting planes all oriented differently which scatter light in many different directions. In fact, the easiest way to turn a strong specular reflector into a strong diffuse reflector is to roughen it up.

1. For instance, take a smooth sheet of ice and scratch it up.
2. You turn a surface that is bright only in the mirror direction of the light source into a surface that bright in all directions.
3. When it comes to planets and moons, the surface roughness is quite high.
4. For this reason, their overall brightness is best described by their diffuse reflectivity.

There are several ways to define and measure the diffuse reflectivity. In the context of planets and moons, the common and perhaps most useful way is to define it in terms of “bond albedo”. The bond albedo is the average amount of total light scattered by the body in any direction, relative to the total amount of light that is incident.

A bond albedo of 0% represents a perfectly black object and a bond albedo of 100% represents an object that scatters all of the light. The earth has a bond albedo of 31%. In contrast, the moon has a bond albedo of 12%. To bring this closer to home, the moon has the same bond albedo as old asphalt, such as is found in roads and parking lots.

The bond albedo of major objects in our solar system are listed below as reported in the textbook Fundamental Planetary Science: Physics, Chemistry, and Habitability by Jack K. Lissauer and Imke de Pater.

Object	Bond Albedo
Triton	85%
Venus	75%
Pluto	50%
Jupiter	34%
Saturn	34%
Earth	31%
Neptune	31%
Uranus	29%
Mars	25%
Titan	20%
Mercury	12%
Moon	12%

As this table makes clear, the moon is one of the dimmest objects in our solar system. If Triton, one of Neptune’s moons, were to become the moon of the earth, then it would be about seven times brighter in the night sky than our current moon. Triton is bright because almost all of its surface is covered by several layers of rough ice.

In contrast, earth’s moon is so dark because it contains very little ice, snow, water, clouds, and atmosphere. The moon consists mostly of rock dust and dark rocks that are similar in composition to rocks on earth. The albedo values in the table above are averages since the albedo varies through time.

For example, the number of clouds covering the earth varies from season to season. Therefore, the albedo of the earth varies a few percent throughout the year. The perceived brightness of a planet or moon (i.e. what we see with our eyes), depends on three things: (1) the object’s albedo, (2) the total amount of light that is hitting the object in the first place, and (3) the distance between the object and the eye or camera that is viewing it.

Planets and moons that are closer to the sun receive much more sunlight and therefore generally have a higher perceived brightness. Also, planets and moons that are closer to the earth have more of their reflected light reach the earth and therefore generally have a higher perceived brightness as seen from earth.

The moon indeed looks brighter than Venus to a human standing on earth’s surface, but that’s just because the moon is so close to earth. *Note that many planets and moons can create small amounts of light through localized phenomena. Examples of such phenomena include lightning, glowing lava, and atmospheric aurora.

What percentage of the Moon is always receiving sunlight?

Phases of the Moon –

From any location on the Earth, the Moon appears to be a circular disk which, at any specific time, is illuminated to some degree by direct sunlight. The Sun always illuminates half the Moon, but, despite common folklore, the Moon does not have a permanent dark side, As the Moon orbits the Earth, we get to see more or less of the illuminated half. During each lunar orbit (a lunar month), we see the Moon’s appearance change from not visibly illuminated through partially illuminated to fully illuminated, then back through partially illuminated to not illuminated again. Although this cycle is a continuous process, there are eight distinct, traditionally recognized stages, called phases, The phases designate both the degree to which the Moon is illuminated and the geometric appearance of the illuminated part. New Moon, First Quarter, Full Moon, and Last Quarter phases are considered to be primary phases and their dates and times are published in almanacs and on calendars. The two crescent and two gibbous phases are intermediate phases, each of which lasts for about a week between the primary phases, during which time the exact fraction of the Moon’s disk that is illuminated gradually changes. The phases of the Moon are determined by the relative positions of the Moon and Sun in the sky. First and Last Quarters occur when the Sun and Moon are about 90 degrees apart in the sky. In fact, the two “half Moon” phases are called First Quarter and Last Quarter because they occur when the Moon is, respectively, one- and three-quarters of the way around the sky ( i.e,, along its orbit) from New Moon. Note that we don’t say 2nd quarter or 4th quarter and instead use full and new, respectively. The relationship of the Moon’s phase to its angular distance in the sky from the Sun allows us to establish very exact definitions of when the primary phases occur, independent of how they appear. Technically, the phases New Moon, First Quarter, Full Moon, and Last Quarter are defined to occur when the excess of the apparent ecliptic (celestial) longitude of the Moon over that of the Sun is 0, 90, 180, and 270 degrees, respectively. These definitions are used when the dates and times of the phases are computed for almanacs, calendars, etc. The percent of the Moon’s surface illuminated is a more refined, quantitative description of the Moon’s appearance than is the phase. Considering the Moon as a circular disk, the ratio of the area illuminated by direct sunlight to its total area is the fraction of the Moon’s surface illuminated; multiplied by 100, it is the percent illuminated. At New Moon, the percent illuminated is 0; at First and Third Quarters, it is 50%; and at Full Moon, it is 100%. During the crescent phases the percent illuminated is between 0 and 50% and during gibbous phases it is between 50% and 100%. The moons orientation (tilt) with respect to your horizon shifts throughout the night because we live under a curved dome of sky. Observers in the Northern and Southern Hemispheres see the moon apparently upside-down with respect to each other.

In the Northern Hemisphere, a waxing moon (from new moon to full moon) increases its phase from right to left, The opposite is seen in the Southern Hemisphere, where a waxing moon (from new moon to full moon) increases its phase from left to right, From the Northern Hemisphere, we look generally southward to see the moon (or sun) crossing our sky. From the Southern Hemisphere, people look generally northward to see the moon (or sun) crossing the sky.

This simulation of moon phases might help.

Why can we see only 50% of the Moon?

Libration causes, over time, around 59% of the Moon’s surface to be visible from the Earth. Libration is caused by the Moon having an eccentric orbit around the Earth, the slight tilt of the Moon’s rotation, and the fact that the Earth rotates.

Why can you only see 50% of the Moon?

Lunar Libration

How much of the Moon’s surface can we see from Earth? Over the course of a lunar cycle we can see more than 50% of the Moon’s surface from Earth. This is because of a combination of effects which are known as “librations” of the Moon. If we view the face of the Moon over the course of its orbit in fast motion, it is as if the Moon is both nodding its head “yes” and shaking its head”no” at the same time. The lunar libration in latitude is due to the Moon’s axis being slightly inclined relative to the Earth’s axis. From our angle we can at one time peek over the north pole of the Moon, and then later in the lunar month we peek under the south pole. Over the entire four week cycle it gives the the effect of the Moon slowly “nodding its head yes.” The diurnal (daily) libration of the Moon is due to the observer first viewing from the western edge of the Earth as the Moon is rising, and then later from up to four thousand miles away to the east as the Moon is setting. This is due to the rotation of the Earth. The difference in perspective between the rising and setting of the Moon appears as a slight turning of the Moon first to west and then to east, as though “shaking its head no.” Libration of longitude is an effect of the Moon’s varying rate of travel along its slightly elliptical orbit around the Earth. The Moon travels faster when it is at its closest to Earth, and its slowest when it is farthest away. Its rotation on its own axis is more regular, the difference appearing again as a slight east-west “no” oscillation. Although the Moon always presents us with the same face towards the Earth, due to its rotation and revolution being tidally locked to the same period, the combined effect of all these different librations allows us over time to see some 59% of the Moon’s surface.

Lunar Libration