Sun - Science topic
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields. It has a diameter of about 1,392,684 km, about 109 times that of Earth, and its mass (about 2×1030 kilograms, 330,000 times that of Earth) accounts for about 99.86% of the total mass of the Solar System.
Questions related to Sun
In mid-July 2022, NASA published the first images taken with the help of the James Webb Space Telescope. The James Webb Space Telescope programme, which has been underway for many years, is now complete and operational in 2022. The images taken with the help of the James Webb Space Telescope are much more accurate compared to the images previously taken by the Hubble Space Telescope. The image presented by NASA shows the result of a study of the composition of the atmosphere of exoplanet WASP-96b. It is one of the first images published on 12.7.2022 and taken thanks to the state-of-the-art James Webb Space Super Telescope located in Earth's orbit. The image shows a graphic depiction of the results of the WASP-96b NASA/ESA/CSA/STScI measurement of the composition of the exoplanet's atmosphere. Through this image, NASA has shown the result of the extremely sensitive instruments found on the James Webb Telescope. The image shows the most accurate measurements to date of the composition of the atmosphere of an exoplanet, or planet, located outside the Solar System. The exoplanet whose atmosphere the telescope has studied is WASP-96 b, a gas giant located just beyond the edge of the Solar System, at a distance of about 1,100 light years from Earth. It is particularly interesting that the telescope detected, among other things, noticeable traces of water in the studied composition of the exoplanet's atmosphere! The collected data also suggest that the atmosphere of this celestial body contains water vapour and clouds. Thus, we are probably gradually approaching research results which will confirm that, with a high level of probability, there is water, Earth-like environmental and climatic conditions and some form of life on many exoplanets located many thousands and millions of light years from our Solar System. In view of this, the technology of space exploration, including the study of what is found on other exoplanets thanks to the James Webb Space Telescope, has made great strides.
Will the James Webb Space Telescope provide answers to the long-standing human question:
Are there other forms of life beyond planet Earth on distant exoplanets, in other planetary systems, in other constellations, other galaxies?
Are there other forms of life, including intelligent other forms of life, somewhere in the Universe beyond planet Earth?
What do you think about this topic?
What is your opinion on this subject?
I invite you all to discuss,
Thank you very much,
I cannot find any paper that deals with this question. There seem to be three schools of thought none seeming based on anything more than speculation.
- the energy received from the Sun is balanced by radiation emitted by the Earth abet at longer wavelengths
- the Earth releases slightly less energy than received as a consequence of global climate change.
- Earth is radiating more heat energy than it receives from the Sun as it cools, a very slow process from the hot Earth interior.
As mentioned in the question the gas and ice planet's energy balance is somewhat mysterious. For example, Neptune is farther from the sun than Uranus but is either the same temperature or slightly warmer.. As a result of processes not fully understood, Neptune emits more than twice the energy that it receives from the Sun 2.6.as does Jupiter (almost twice as much as received and Saturn 2.3 times the energy from sunlight is radiated into space. It is odd that Uranus while it does generate more heat than it receives, much less than the other three aforementioned planets, it also has another energy puzzle both its polar regions have the same temperature even though one of the two is in total darkness. It appears to me that in this age of climate change comparative planetology is a useful tool to understand our planet as well.
a lot of literature review describe the uses of dyes such as (methylene blue ,methyl orange ,rhodamine B ...etc) as indicators for nanoparticles when using for photodegradation .
but when i try to expose this dyes for direct sun light or for uv lamb... this dyes were degraded and the intensity of color became less ..
my question .... what are the benefit of nanoparticles for photodegradation if the direct sun light or uv lamb It is responsible for photolysis of dye?
any independent research available regarding the storage of energy in a very efficient battery for retail solar panels vs home wind turbines? Cherish your feedback.
I am currently exploring GMAT R2020a. There are few concern's which I am not able get hold of about the software.
1) In regards to the solar panel, is it possible to get the power profile, i.e., how much power is being generated, as a test case for example, while the satellite is tumbling slowly simultaneously can we get the power generated ? ( I can only see the specs that I can give as input for the solar panel such as BusCoeff1,2,3 etc)
2) As a continuation of the first question, Is it possible to implement an attitude control such that the satellite can be pointed to sun or earth? To the extent I have explored I can see that attitude parameters such as quaternion can be extracted for example in "ThreeAxisKinematic" model (without a control).
3) Is there an attitude estimation or determination built-in? (Because the Hardware that one can attach to the spacecraft does not include any sensors)
Any help would be appreciated
This is only My perspective
Based on the nebular hypothesis, the first formed planet after sun should have most dense planet. Its our earth followed by mercury, venus, mars, pluto, neptune, jupitor, uranus and saturn. There are two phase of formation of planets in our solar system.
Earth, Mercury, Venus and Mars (based on Density)
Pluto, Neptune, Jupitor, Uranus and Saturn(based on the density)
The Last formed planet should be Saturn, that is why it has ring, which is the rest of the nebula remains.
After all these formation, an external fast moving terrestrial body collide with our solar system and change the position of the planets. Also forms the satellite system of the planets. Still the denser planets move towards the Sun and the collision should have taken place between the first phase and second phase of the solar system( The place where now seen the asteroid belt, where pluto's position). This affects more to Pluto and that is Pluto revolves in long different way path to sun.
We consider gravitational potentials, which let planets orbit around the sun. This view implies a remote non-local impact of the sun on the planets and vice versa.
But in fact, the gravitational fields have an energy density, which is present locally. The energy density E quadratically depends on the field strength and is given by E=-g²/(8πG), g=MG/r². G is the gravitational constant, r is the distance to the centre of mass M, which generates the gravitational acceleration g.
With the locally available energy density, the gravitational force also becomes a local force.
The gravitational force on an object, which contributes to the gravitational field, is given by the derivative (gradient) of the total field energy in respect to the position of the object.
This force is an interaction between gravitational fields. The energy density of the gravitational field of the object decays with the distance d from the object to the fourth (~1/d4). The interaction of the local gravitational field of the object with the omnipresent background field, therefor is a local interaction.
The idea of a remote gravitational interaction on a distance is a blatant chimera!
The highlighted relation between energy density and force applies to all kinds of force fields.
Hello everyone, I participate in a project in which we intend to forecast the demand of customers With installed and photovoltaic panels. These are the so-called microinstallations, i.e. their power does not exceed 40 kw. Due to the fact that the distribution system operator installs two-way meters that measure consumption and delivery, we are not able to find out what the customer's auto consumption level is without additional metering. When it comes to forecasting the demand of these customers, usually after the installation of photovoltaics, customers most often decide to install additional receivers so that they can consume the energy produced. Increasingly, these receivers are heat pumps. Thus, the demand of such customers changes dynamically with the change in temperature. To solve this problem, we believe that it will be appropriate to use, for example, linear regression with explanatory variables such as temperature, sunlight, humidity. As for forecasting what customers give to the grid, in this case an efficiency matrix will be built Determining how much energy is given away at a given temperature and sunlight Along with taking into account the Parameters of the sun, i.e. azimuth and Height of the sun. I would like to know what methods do you use to solve this type of task?
Hi, everyone! when I scan the coordinate in Gussian software, The log file shows the following error:
New curvilinear step failed: FormB failed.
Error imposing constraints
Error termination via Lnk1e in /home/Gaussian/Gaussian/g09/l103.exe at Sun May 29 18:16:46 2022.
Has this ever happened to you?
Industrially PV System is widely used. But academically using Sun path diagrams is outdated or are there any other advantages?
I am working on making a ice-cream tricycle into electric. The main idea is to reduce human effort in driving the tricycle especially uphill. I've seen people pushing the tricycle whenever there is need to go up a hill. This will also enable him/her to cover more distance with less effort.
First i want to use a solar system to charge the battery that we will install on the system. The mass of the tricycle being driven will be between 150kgs to 250kgs. This battery in turn will be connected to a motor which will drive the tricycle.
Secondly, if there no sun light i want to use Regenerative braking to charge the battery which will be able to produce more power when driving down hill.
Thirdly, just to add more, if possible there will be pedal assistance to charge the battery.
This system will not completely rely on electric driven system but only when needed.
I need more guidance related to my work.
What type of motor to use? What software will be used to simulate the design of this whole system?
And any more input is welcomed.
Dust aerosols have a strong scattering peak at small scattering angles (near the sun). The usual single or double Henyey-Greenstein phase functions are convenient in general but do not peak enough to emulate that strong peak in the circumsolar region. Is there any other simple phase function that would provide better results?
Is there a way to avoid starlight to find planets?
For this, let us first consider the earth and the sun. The world revolving around the sun star follows a method (rotation) just like the exoplanets. However, these turnaround times are different. If the value in the planet finding chart is first constant then decreasing then increasing when the planet is accelerating. So if it turns out to be a planet. What else can we say? So, when we accelerate the orbit of a planet, it means that we will be exposed to much less starlight because it will pass quickly from the sun, that is, the star. Orbit means gravity. If the gravity increases, the orbit, that is, the gravitational relationship of the two objects to each other (here the sun and the earth), the orbital speed will increase and the light scattering from the opposite star will decrease. So let's use SIR ISAAC NEWTON's formula G.m1.m2 /r'2 and derive something new.
The formula for going to exoplanets might be this: g. c(luminous intensity of star) /v(rotation rate of earth or exoplanet)
Gezegenleri bulmak için yıldız ışığından sakınmanın bir yolu var mıdır?
Bunun için öncelikle dünya ve güneşi düşünelim. Güneş yıldızı etrafında dönen dünya tıpki ötegezegenler gibi bir metod (dönüş) izler. Ancak bu dönüş süreleri farklıdır. Eğer gezegen hızlandığı vakit gezegen bulma tablosunda değer dalgalı fonksiyon once sabit sonra azalan daha sonra artan ise. Böylece gezegen olduğu ortaya çıkıyorsa. Başka ne söyleriz? O halde bir gezegenin yörüngesini hızlandırdığımız vakit güneşten yani yıldızdan hızlıca geçeceği için yıldız ışığına çok daha az maruz kalacağız demektir. Yörünge kütleçekimi demektir. Eğer kütle çekimi artarsa , yörünge ;yani iki cismin birbirlerine olan kütleçekimsel bağıntısı.(burada güneş ve dünya olur) yörünge hızı artacaktır ve karşıdaki yıldızdan ışık koparma azalacaktır. O halde SIR ISAAC NEWTON’un G.m1.m2 /r’2 formulünü kullanalım ve yeni bir şey türetelim.
Ötegezegenlere gidebilme formülü bu olabilir: g. c(yıldızın ışık şiddeti) /v(dünya veya ötegezegen dönüş hızı)
Re: “Deep Down And Dark - Stawell’s Genius Lair” (Cosmos Magazine, Issue 94) -
On p.34 is the statement, “Because the Earth is physically moving through space as it travels around the Sun, researchers think that we might see a change in the amount of dark matter we see as we move …” This sounds eerily similar to the Michelson-Morley experiment of 1887. This experiment compared the speed of light in perpendicular directions as we travel around the Sun in an attempt to detect the “luminiferous aether”. But this experiment yielded no results to prove a difference between the speed of light in the direction of motion through the presumed aether, and the speed at right angles. Then, less than 20 years later, along came Albert Einstein and Special Relativity with the answer to the puzzle … the flexibility of space-time.
Perhaps WIMPs and so on are the modern equivalent of the aether. The answer to the puzzle of dark matter might be the modern version of space-time’s flexibility … which could be the idea that mathematics doesn’t merely describe the universe, but that the universe is actually composed of maths. Cosmologist Max Tegmark from MIT (the Massachusetts Institute of Technology) is the best known promoter of this idea. My personal belief is that the mathematical universe could be built using binary digits, Mobius strips, figure-8 Klein bottles, Wick rotation, and vector-tensor-scalar geometry.
Another counterpart to aether and WIMPs is the proposed planet Vulcan. In the 1800s (even as early as the 1600s), some people proposed this planet to exist between the Sun and Mercury in order to account for irregularities in Mercury’s orbit (its precession). The need for the planet as an explanation for Mercury's orbital peculiarities was later rendered unnecessary when Einstein's 1915 theory of general relativity showed that these are well-explained by effects arising from the curvature of spacetime caused by the Sun's mass.
Finally, the orbits of certain Trans-Neptunian Objects may likewise have nothing to do with astronomy’s versions of the physical aether and WIMPs (the physicality of Planet 9 or a mini black hole). Mercury’s large precession (due to its closeness to the Sun) may disprove the existence of Planet 9 because a diagram of Mercury's orbit can display an ascending pattern while its perihelion on the opposite side of the Sun maintains a constant level, while a diagram of the orbits of certain Trans Neptunian Objects displays a (less orderly) ascending or descending pattern on one side of the Sun while the greatest part of the orbit of the alleged cause of their perihelia being attracted to more-or-less the same point in space (Planet Nine) is on the other side of the Sun - the actual cause for the attraction of their perihelia would be precession, which affects all objects in the solar system.
Fig. 1 – Mercury's orbit with its perihelion’s constant level on the left and ascending pattern on the right
Fig. 2 – Trans Neptunian Objects, a.k.a. TNOs, and Planet 9 with ascending pattern of the TNOs on the left and the supposed cause of the positions of their perihelia - Planet 9, with the dotted red orbit - on the right
I want to study some events encountered by the Parker Solar Probe (PSP) satellite using different statistical tools. I have downloaded data from the websites recommended by different researchers, however I am facing a problem reading the .cdf file format of the data. If you provide all available data (in minutes resolution) of some specific event days, it would be a great help for me.
In region that climates have a high heat or high level of sun light we use nets to protect plants from these high radiation, why using green nets especially?
What device can I use to store heat inside parabolic solar tent dryer for drying of agricultural produce. The device will be inside the dryer and store heat during the day from sun light and then emit the heat inside the dryer at night to compensate for absence of sun at night. Please , this I what im currently working on .im a master student in university of ilorin, Nigeria.thanks for your kind advice and my breakthrough
Please I am working on simulation of solar still I wanted to add a solar radiation so I used solar loading and used solar ray tracing and used solar calculator to define my sun direction vector instead of entering it manually and my problem is that the sun rays seems to be under the solar still not above it so I want to learn If anyone knows how to probably define the sun direction vector from a certain correlation or from the solar calculator it seems I doesn't understand the mesh orientation how to define it
Field Conditions such as loads, sun intensity etc
also if I could 3D model a solar cell and induce cracks and defects all in a software to help me get the efficiency of the Cell.
I have recently collected BSG from a local brewery, since I live in Himachal- sun dry method is not really helpful as it is continously raining here.
I have separated 12 kg BSG approx in 6 wide trays and kept it for sun dry for 6 days, weather wasn't supportive but atleast it got little better and was able to evaporate the dripping water.
Now my BSG is very moisture loaded but not dripping wet, so I kept in dryer cabinet at 60 degree Celsius for 7 to 8 hours.
I have been repeating this procedure, it has been almost 6 days now but no results.
It is still very much loaded with moisture.
Can you suggest me better ways of going through and drying it as fast as possible.
I have been using a RGB camera with a fish-eye lens to automatically take pictures of the sky every 5min.
I would like to use the data to estimate the aerosol properties. This is possible because the amount of scattered light into each pixel depends on the scattering angle of the incoming Sun light, and on the aerosol properties (e.g. phase function, size distribution, etc.). However, I need to know the pointing of each pixel in the image (i.e. azimuth and zenith) to better than 0.1 deg.
That is why I need to know the lens equation (relation between pixels and viewing angle) which is measured from the optical axis (which might not necessarily be the central pixel due to misalignment).
Any ideas or suggestions?
Any good references?
Thanks in advance,
Dr. Adele Diamond and other researchers used Day/Night test or Sun/Moon to measure the inhibition in young children.
In the context of the PFO-CFO Theory, we expect a possible powerful protuberance activity of the Sun in the near future. It is possible that it could influence significantly the radiation environment over the near-Earth space.
We consider the protuberance activity as a result of the electron-gas temporal accumulation in the layer between the solar core and radiation zone and the comparatively cold sunspots as the effect of the electron flows incapable of making their ways through the radiation zone. According to the Theory, the protuberances contain the radioactive solar substance from the core/radiative-zone boundary; therewith, this solar substance is initially rather cold, steadily warms in the protuberance jets, and, thus, increases the speed of its movement in the space. According to the Theory, no fusion reactions proceed in the Sun and the chemical elements form from the solar substance by the mechanism that is not described here.
A lot comes together for the Earth orbiting the sun to let us know there is a mystery before us if we look at the archaeology of Earth’s astronomy. Thus, does a lot come together considering the archaeology of other star systems as well that can indicate to its intelligent life that they are part of something larger than themselves, as well. We can infer the existence of a planet around a star we cannot see, but can we say something about the archaeology of its people as well. I treat this a bit in Archeology of Other Star Systems at
The paper is at:
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Or you can download it below....
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During the study of photocatalytic properties of Zno/Cuo i kept the samples of methylene blue with certain amount of photocatalyst in sunlight for degradation.
After some time the colour of methylene blue become disappred as it seems degradation of dye was done.But when i removed the samples from sun light the blue colour has come again.
Why this was happening.?
If I were to make a half dome as an umbrella to protect a city from rain and sun how would I proceed. Are there special materials or do you have an idea on how to make this? What do you say about an energy shield ?
Am looking for research -related to this particular phenomenpn; Do PV or solar collectors have an influence on climate change especially rise in temperature or an accelerated activity of the sun?
I'm using ANSYS (2021R) Steady-State Thermal simulating the heat transfer of a spacecraft's thrusters onto the rest of its thruster bay and components within.
I'd like to also consider the temperature effects that the sun may cause on my system.
Does anyone know of any good methods to simulate this effect?
Currently I'm using Steady-State Thermal, but I'm open to other Workbench analysis systems.
I'm not too familiar with anything besides Steady-State Thermal unfortunately but willing to adapt and learn.
My idea so far is to just create a sphere that will represent the Sun, but the problem with this is that SpaceClaim (CAD Software) won't let me add anything that large or that far away from my system.
If I shrink the "Sun" and move it closer, I'm not sure what to make its temperature or heat flux, since obviously if I keep it at its surface temperature, it being closer will cause a larger effect on the system.
Any help is appreciated.
I am analysing ground measured solar irradiation data for photovoltaic applications. for some days, I noticed that DNI is higher than GHI. Can someone please explain why?
Consider that there was no flag during these data points. Please see the attached figure. The sun Elevation angle at noon was 45 degree towards South.
In addition to CO2, methane is also one of the main greenhouse gases, and in a few dozen years, when the eternal scarifier on the Siberian tundra and other places of the Arctic Circle methane can become an even more significant greenhouse gas.
Besides, the analyzes of cyclical activity of the Sun conducted by cosmologists show that in a few decades the activity of sunspots and more harmful to life and more intense energetically will reach the Earth's wavelengths of visible and invisible spectrum.
The increase in temperature will cause desertification of green areas, drying of biomass and an increase in the scale and amount of emerging fires and volcanic eruptions. these processes will intensify and accelerate the global warming process that is currently under way faster and faster.
Do you agree with me on the above matter?
In the context of the above issues, I am asking you the following question:
Why according to the forecasts of climatologists, the global warming process in the next few decades can significantly accelerate?
I invite you to the discussion
Thank you very much
Dear scientists, I had very confusing Issue in my PHD on PV generation long term yield, how do use units of angle of incidence in degrees or in radians?
I used isotropic irradiation model:
I used long term radiation data from PVGIS european data base, the angles is in degrees. for DNI and DHI, all data are given on horizontal plan, from TMY data base, so I used the following transformation equations to get the total in plan radiation using all angles in degrees and take absolute of any cosine or sine result in negative, unfortunately the total in plan radiation is less than PVGIS results by more than 27% less than European commissioning simulation calculations.
Solar Paint technology:- Solar paint, also known as photovoltaic paint, is exactly what it sounds like! It’s a paint that you can apply to any surface that will capture energy from the sun and transform it into electricity. The paint would essentially be your average paint, but with billions of pieces of light-sensitive material suspended in it, material that would transform the typical paint into superpowered energy-capturing paint.
Present I am working on different technologies included in itself and how to develop the infancy to developed stages and what are the implementations and challenges are facing in the future.
at large scale, do earth goes around sun or particles of the earth goes around the particles of the sun?
i am proposing new theory which says; the Gravitational force in between two objects depends on the most probable distance in between them.....
Preprint THEORY OF MOST PROBABLE DISTANCE
my dear unique scholars welcome to your valuable feedback, answers, comments....
Respected Sir, Please read the article below. My article will totally revolutionize the understanding of our entire Universe.
Gravity definition :
Gravity is the force applied over the mass due to the interaction of waves and the mass is pushed towards the area of low frequency waves .
* Space is the constant source of high frequency waves. This high frequency waves vibrate our earth and the earth releases low frequency waves. The interaction of high and low frequency waves pushes the mass towards the low frequency wave creating earth.
* The earth is not pulling us. We are all getting pushed towards the low frequency wave creating earth by the high frequency space waves.
WORKING MECHANISM OF ENTANGLEMENT WITHOUT
The Entangled waves are continuously feeded energy by Universal frequency waves.
Theory of oneness :
Nothing is moving in the Universe and the shift in wave position and it’s dimension from one place to other place makes us to believe as moving.
1. We are not moving and we are shifting our wave position from one place to other place.
2. The Earth is not moving and the earth is shifting it’s wave position from one place to other place.
3. The Sun is not moving and the sun is shifting it’s wave position from one place to other place.
4. The Galaxies are not moving and the galaxies are shifting it’s wave position from one place to other place.
Please read the Attachments Below. Kindly help me to publish my article.
Here we show that free fall in a gravitational field must be detectable by an experiment, while inertial motion is not detectable by any experiment. Since gravity is not annulled in free fall in a gravitational field, gravity is not rendered, somehow, shielded or immeasurable. This is contrary to electromagnetism, that can be shielded.
We are harmonizing "free fall" as defined under GR, with "inertial motion" as defined under SR, extended under GR, and even indepently from gravity, so it can apply to Cosmology, using the same notion of 4D spacetime but allowing the metric to be respectivelly different.
Free fall in a gravitational field is not inertial motion to an arbitrary observer, not even locally, only to comoving observers (note that, in SR and GR, comoving observers have identical velocity and position). But, even atomic clocks, by definition, or a person, cannot be entirely comoving, experimentally. In GR, it is the equivalence principle that does not let you feel it, IF you are entirely comoving with yourself, which no one, nor any clock, can, experimentally. This defect can be acceptable, while small, but the misconception remains. This means that one should NOT confuse free fall in a gravitational field with inertial motion, they also belong to different types, as shown.
In this discussion, arguments are non-circular. This discussion does not suffer the linguistic and logic problems, noted by Einstein and others, in Newton's First Law -- what is the definition of a straight line, to be able to denote a straight line? A "traveling wave" is, indeed "a wave that travels" as the current, physics college textbook Serway says, but that does NOT convey any information ---- it is a circular definition. Physics is still full of those. It is also pointless to discuss about names, different national languages have different names for the same physical concept, for example. What is one to do?
Let us follow a semiotic road in logic, in recent advances in theory of types in mathematics and TCS (theoretical computer science), more basic than set theory, instead. Nothing is more fundamental than theory of types in maths, used in TCS. So, all circular references have no logical reason to exist, we just have to go deep enough to TCS and type theory, in this view. Not even "inertial motion" resists, as we shall see.
The term "inertial motion" is thereby treated as an arbitrary name, a reference, a truth value, and is considered not relevant here, could be "sdrufs". We discount the circular, logical problem, likewise, of defining a "straight line." But, how can we discuss, when a veritable Babel tower is in our discussions?
Simple, we do it intuitively everyday, in our laboratories of nature, and is explained in semiotics. If we were to talk about Bessie, we would not have to drag the cow from the barn, we just say "Bessie" -- the arbitrary name "inertial motion" links the truth-value to the exact referent, of many, the physical object in "Inertial motion" ---- which is what we talk about. What is also relevant here is the meaning, the sense, the truth-condition that the duple (reference, referent) denotes, forming a triple (reference, referent, sense).
This triple is further made unique, in semiotic considerations in the MCWG group, by adding trust:
trust: a non-localized "field" created by an intrinsic collective effect, that is directly and indirectly defined by knowledge (what you know you know, and know as to exemplify); that which is essential to a communication channel but cannot be transferred using that channel (Gerck, 1998).
Trust, as indicated above, binds all three elements together, within an extent, a measure. This forms a "hard" object, a "particle" of understanding -- not unlike a proton being studied as a set of three quarks and a confining field -- and this we study as "inertial motion", called by its quite arbitrary name, but a distinct physical object and a definite meaning, within a defined extent of trust in matters of physics.
Please feel free to, consistently, use any name you would like, physics is name-agnostic. The same phenomenon applies to any other name. Now, the language being clear and unique, in any language, we can go on to the physics.
If one is in free fall toward the Sun, the Sun gravity does not disappear! What it does happen, is that that, locally, one seems to experience no gravity -- but what does it mean, what is the truth-condition? Perhaps, gravity was somehow perfectly shielded, the Sun did disappear, the body is somehow suddenly at rest, the body is momentarily in inertial motion, or something else happens.
The entire Sun is still there, 100%, its gravity is still there, 100%, it was not shut-off, even the slightest, it is not negligible at all, spacetime is not even locally flat - someone else certainly experiences gravity at the same point if not in free fall; suppose one just passes by, when one is free falling, not anyone with a rocket, necessarily, but at the same point in spacetime, neglibly close in (t, x, y, z) -- just not exactly the same v.
Let us look at it another way, introducing consciousness, as often done in physics -- without naming the "demonology". The Sun does not know one is in free fall, neither the other planets and bodies. They don't go fly off because one is in free fall somewhere, gravity is neither negligible, nor disappears, not even momentarily, not even locally. Spacetime, curved, does not change because someone goes in free fall.
Also, regarding some differences ... when one is really in free fall, it is not only relative to the Sun. It is to every gravitational influence, even if the gravity field is dominated by the Sun.
Further, two satellites in orbit around the Earth must not be in free fall, they are just following a geodesic dominated by Earth. It is an extended Galileo's inertial principle, also called extended Newton's first law, valid for such non-inertial movement.
Another proof, if needed, is also that the satellites do go around, which is not a straight line, which free fall does not do.
Any satellite, also the Earth, is not in free fall -- just non-technically said to be in "free fall". This is demonstrated absolutely, in spacetime terms, not meaning that an absolute reference frame is to be used, by measuring the curvature of the worldline. No curvature means no acceleration, also in flat, Minkowski spacetime.
Motion is not detectable if it is inertial. Inertial motion is a diagnosis of exclusion. Free fall qualifies as inertial motion to observers comoving with the free fall (note that, in SR and GR, comoving observers have identical velocity and position).
Therefore, one can say that motion is not detectable only if it is inertial.
There are no frames in inertial motion where the laws of physics are different to inertial observers. Free fall in a gravitational field is not inertial motion to an arbitrary observer, not even locally, only to comoving observers (note that, in SR and GR, comoving observers have identical velocity and position), thus it has two "strikes" and is detectable.
Also, one can use Newtonian physics arguments, with no maths, SR, or GR -- in Newtonian mechanics, any non-comoving inertial reference frame cannot be reached at constant velocity from a free fall body, as close as it may be (without being identical -- keeping the non-comoving condition). In other words, any non-comoving reference frame in free fall would be different in terms of laws of Newtonian physics, from any inertial reference frame, hence, it is not inertial. Let us look further at a Newtonian observer in free fall. The laws of Newtonian physics will be different, even locally, to any observer but at the same material point (i.e., same position, same velocity -- comoving).
Or, one can also use those consequences with students, and use for, hopefully, an illuminating discussion. There are the many other reasons, not all listed above, why free fall in a gravitational field is not undetectable, and the observer is not "at rest," even to the very observer falling, only to comoving observers.
NAMES IN PHYSICS AND THEIR REGIOBS OF VALIDITY
Names seem to not matter, as expected, in physics. it would seem that it does not matter, then, if someone, for example, chooses a geodesic to extend Newton's First Law, overcome beautifully our limitation then (to define "straight line"), and designates it as an extended "inertial motion" -- the geometric basis is the same, the physics did not change. Or, like Mashhon, describe an infinte family of comoving observers, 3D, each one as a flash in time. One would seem to need less mathematics, it can all be solved in 3D +1D, even 3D, not needing 4D. But the context is just more limited, the region of validity is less, as we show next.
It is physically limiting to use names that do not distinguish curvature as stretching (as done in 4D spacetime), only considering curvature as bending. The spacetime that was being considered is flat, it can be seen in 3D like a stretched, flat pizza dough. The spacetime is flat but if the world trajectory is curved, it still fits with curvature as intrinsic, as stretching, so not just world straight lines "fit" in flat spacetime!
The 4D spacetime, in SR or GR, therefore, works for world-curves, as they may curve, in the world we see as flat spacetime, locally, as SR, or curved spacetime, as we see in GR. Only the 4D spacetime formulation of SR and GR can do that, we cannot use lesser dimensions, may be more.
The visible world, however, as viewed, is NOT 4D spacetime, it seems at first sight. The world is apppearing to us as 3D +1D, or 3D plus time as parameter. But, the world is governed in 4D spacetime, which manifests itself through laws that 3D or 3D+1D cannot represent, but we can see in everyday experience -- just like we do not see the Earth going around the Sun, we see the Sun going around the Earth, apparently, but we do have seasons, and the ancient Greeks measured the circumference of the Earth, with no rockets, quite correctly, through mathematics.
CLOCKS AND MEASURING TIME
A clock, by definition, or a person, cannot be entirely comoving. It is the equivalence principle that does not let you feel it, IF you are entirely comoving with yourself, which no one, nor any clock, can. Thus, while inertial motion is not detectable by any experiment, free fall in a gravitational field must be.
Thus, as far as clocks are concerned, anything that is non-comoving with the central point of a free fall should be affected, including centripetal and coriolis forces, which are representable, therefore exist in the GR formalism. Any contrary result is to be understood as false under these definitions.
But human observations, as d'Espagnat agrees, must serve as criteria -- not as definitions of reality and truth.
The experimental difficulty to measure time at all, or to be be comoving, can be removed under the criteria that small defects are acceptable, vanishingly small to some, but still the main objection remains, as shown next.
A rock thrown on Earth, with a clock attached to it, will follow an accelerated motion, then decelerate to a stop. After the apex, the rock is in free fall in the gravitational field, including the Earth, the Moon, the Sun and other influences, here assumed as all just gravitational.
The trajectory can be calculated using SR in the 4D spacetime formulation, but not using the original SR formulation by Einstein. The original formulation, however, is still taught today in US colleges and Ivy League universities in undergraduate studies, for example using the physics textbook by Serway.
The clock, comoving with the rock, will measure the proper time, an invariant in 4D spacetime, calculated by the inverse function of the arc-length function, including any contributions, and the space coordinate will be zero, it does not travel in space. To an observer at rest in the ground frame, the rock does travel in space, space coordinates change, the time measured is dilated, and the rock, after the apex, is in free fall and not in inertial motion. The misconception, shown here, confuses free fall in a gravitational field with inertial motion.
Further, those concepts are not of the same type, in type theory in mathematical type theory and TCS terms, which are more fundamental than physics, and setting the very language of physics as truth-conditions, their meaning, and referent.
Physics cannot confuse these types, they are not just names, arbitrary. Whatever name we use, they must have the meaning and referent, in general, that the physics laws designates in nature, and they (not even the names, technically understood, in general) can be different.
There is no point in discussing only the names, free fall or inertial motion, different languages use different names, but we have tried to differentiate what they mean and point to, within the trust of the same physics, what we understand of nature. This is should not be fragmented, the names can.
Let us discuss the physics. The names change at will, physics can also change, but we need to ask what inertial motion means, what free fall means, in nature, and what they pont to. These are fundamental questions, and nature does not change, so our task is clear.
The author acknowledges contributions by Stefano Quattrini , Edgardo V. Gerck , and two anonymous reviewers.
We are harmonizing "free fall" as defined under GR, with "inertial motion" as defined under SR, extended under GR, and even indepently from gravity, so it can apply to Cosmology, using the same notion of 4D spacetime but allowing the metric to be respectivelly different.
In SR and GR, accelerated motion is defined absolutely, for example, with no absolute reference system or geodesics, of course, by extrinsic and intrisic geometric properties of the curvature.
So, it does not matter if someone chooses a geodesic to extend Newton's First Law, overcome beautifully our limitation then (to define "straight line"), and designates it as an extended "inertial motion" -- the geometric basis is the same, the physics did not change, the context is just more limited.
It is limited to not distinguishing curvature as bending, only considering curvature as stretching, in spacetime -- the spacetime that was being considered is flat, like a stretched, flat pizza dough. The spacetime is still flat if the world trajectory is curved, not just world straight lines "fit" in flat spacetime!
It all works for geodesics, world-curved as they may in the world we see as flat spacetime, locally, which is NOT spacetime but governed by a flat spacetime, there is no ontological status anymore, and this is beautiful, not just right. This is also, perhaps, new to philosophers.
But... it does not work in GR, under free fall in a gravitational field, because the spacetime is curved under gravity, as bending. So, inertial motion must be redefined, not as a name, but as a truth-condition. This is how GR actually exists, we are NOT reinventing the wheel, just may be going a bit further into what GR means, not just what it says.
On the other hand, we are investigating what gravity, in nature, provides under the arbitrary human name "free fall". This is certainly fixed under the meaning of what we call "free fall", and the object. The same for the arbitrary name "Inertial motion" that we fixed under the meaning of what we call "free fall", and the object.
We also investigated if those are meanings that physics denote by its laws in nature, GR, SR, and others, no matter the name. It is a two-way process: is physics denoting the same as nature, under general assumptions, not casuistically, and vice-versa?
We have to resort to sense, referent, and trust (as a social construct, a collective effect of milions, that neither friend nor foe can change, not a perhaps misplaced confidence on any source or sources, nor perhaps hand-picked by one, nor bias), not names.
That means that what we call inertial motion, under any other name, or understanding, will behave (sense) and point to the same object (referent), as trusted in physics. The same for free fall. A rose, by any other name, would smell the same, is the gist as captured by the poet.
DISCLAIMER: We reserve the right to improve this text. Questions, public or not, if on-topic, are preferentially answered here. This will help make this discussion text more complete, and free space below for questions. References are provided by self-search. This text may be modified frequently.
At 10am, the view of the sun from your solar farm is obscured by thick cloud. The DNI drops to 300 W/m2 and the diffuse irradiance is 150W/m2. Your panels are oriented due south and mounted at a tilt angle of 40°.
Using this information and the graph below showing the position of the sun, calculate the total irradiance on your panels. in W/m2 .
The cells in the panels that make up the modules in the solar farm of Part 1 have been characterized as having the following PV parameters (tested under AM1.5 conditions): JSC=40mA/cm2, FF=75%, VOC=0.7V.
For illumination conditions giving 700W/m2, calculate the output power density of your cells (mW/cm2).
You may assume that FF remains the same, but VOC and JSC do not.
Also, assume nkT = 25 meV and that J0 remains constant.
I search for a library or a method to determine the sun shadow or rays on a part or side of buildings . The building's position can be get throug geo database or geo location. Which algorithms and language should be efficient. Is there any special 3D library to manipulate such data?
I thank you forward for your help or suggestions.
This is an usual phenomena that the poor people remain more longer exposed to sunlight, specially mid day sunlight . Because of their nature of work engagement they have great advantage to get exposure to sun light, does this support /compliment COVID prevention in any way . As there are some research instances where the correlation of Vitamin D in COVID prevention has been highlighted . Any clear scientific evidence on that ??
Hello, I am a management student and I am trying to work on "sustainable energy management" for my masters thesis
I know the topic should be narrowed, so I am looking for suggestions, what can be interesting to talk about in 2021, maybe something related to electrical cars and the sun's energy.
Thank you in advance
I am looking for the following article for a student at the University of Burgundy : - A Monte Carlo Study of Confidence Interval Methods for Generalizability Coefficient / Zhehan Jiang, Mark Raymond, Christine DiStefano, Dexin Shi, Ren Liu, Junhua Sun
Published August 7, 2021 Educational and Psychological Measurement Our library can pay this interloan library with IFLA Vouchez. Thank you for your help
The cost of solar panel sun sync system is very high. Without sun sync efficiency of panels drop drastically on change of incident light angle. Efficiency also drop on increase of panel temperature. Is it possible to manage full efficiency of solar panel by making panel sun sync and cooling of panel without additional expenditure or energy use?
Hello, I'm interested in looking at long-term (100+ year) measures of magnetic storm sudden commencements and, also, coronal holes. Is there a convenient list of SSCs? Have coronal holes been measured in some way for long periods of time? I already know that I can, for example, look at the 27-day autocorrelation of geomagnetic activity, but something more directly related to the Sun would be appreciated.
Parker Solar Probe, NASA's mission for a better understanding of the Sun's environment, is continuously providing data from different encounters. Past encounters were especially during the solar minimum period. I am really curious to know in detail why the study of fluctuation on the magnetic field and other solar wind parameters data during solar minimum period? What are the major advantages of its study? I am looking for descriptive answers. Please help. Thank you.
Astronomers estimate that there are a lot of galaxies in space, in which there are millions of planetary systems similar to the best known Solar System, ie the planetary system containing the Earth on which we live.
Many of these planetary systems similar to the Solar System may be planets similar to Earth.
This similarity mainly affects the size and distance from the sun.
Because, apparently, in the meteorites that fell to Earth, fossilized creatures similar to bacteria were found, so life on Earth could also come to Earth from outside the Earth.
So there is a high probability that our Earth on which we live does not have to be the only planet in the Universe that has developed a life in the richness of ecosystems composed of various forms of flora and fauna.
Some researchers in this field argue that from a statistical point of view it is almost impossible that only developed life forms existed on the Earth.
So the current question is now: How many planetary systems can there be in the Universe, where life could or should be created?
Our opinion is expressed in the lecture given in 2019 in Amsterdam in the context of the PFO-CFO Theory and in the subsequent works available by the addresses:
Ostrovskii V.E., Kadyshevich, Solar protuberances: their nature, function, and potential threat to the Earth's population in the context of the PFO-CFO Theory of Solar System Formation and Transformation (Presentation); https://www.researchgate.net/publication/333754868_Solar_protuberances_their_nature_function_and_potential_threat_to_the_Earth's_population_in_the_context_of_the_PFO-CFO_Theory_of_Solar_System_Formation_and_Transformation_Presentation;
I have plotted solar wind parameters data (such as IMF-B, Vsw, Nsw, Tsw) by Parker Solar Probe, it shows maximum fluctuations nearby Sun (around 0.17 au for second encounter data, and around 0.13 au for fifth encounter data). What are the reasons behind this? This might be a basic question, but I am looking for some good references with detailed explanations. Thank you.
I was looking for some sources (if available), which contain information about geomagnetic events, ICMEs, Flares, SEPs during the different encounters by Parker Solar Probe (PSP). I am working on the analysis of abrupt fluctuation in solar wind parameters during the encounters by PSP. I would really appreciate your suggestions. :)
As the quantum detectors get more sensitivity they should be picking up fluctuations in the local gravitational potential and electromagnetic background fields of the earth. But I have not seen anyone running a detector continuously for the days or weeks or months needed to do the required correlations to trace things out. Nor, do I see anyone using time of flight (array imaging with speed of light and speed of gravity) to correlate and image and characterize sources.
For many years I have been tracking every new gravimeter design - traditional sensitive accelerometers, atom interferometer gravimeters, MEMS gravimeters, electrochemical gravimeters, electron interferometer gravimeters, Bose Einstein gravimeters, and many others. If I left out your favorite gravimeter (also gradiometer and other names), tell me and I will add it to my list.
The problem with most of them is they are too slow to sort out natural, man-made and purpose build signals. You need at least Msps (mega samples per second) which is 300 meters resolution for many global sources. But there are many ADCs (analog to digital converters) that can do Gsps (giga sps) for relatively easy correlations.
The seismometer networks pick up a small bit of gravitational noise, as do the magnetometer networks, as do many electromagnetic sensor networks. It is taking a long time for all the groups to sort out, mostly "not my job". But if there were some decent, low cost sensors that were sensitivity enough to track acceleration in real time (Gsps is real time for these sorts of things) maybe we could separate and characterize the sources.
I am writing to everyone, so some groups are very sophisticated but don't do practical things. And other groups have practical problems, but no time or resources for theory. And all the groups are struggling with sharing data and models, ideas and problems globally.
Anyway, I know there are lots of "quantum" and "condensate" and other devices out there that have noise. I am asking all the groups to share their noise and sort it out. Much of the "kT" noise is partly magnetic, partly gravitational and much human activity. It is possible to separate. But it means serious effort for global correlations. Now the radio telescope groups have "correlators" and seismic groups have their methods, and electromagnetic groups their methods, and gravitational groups their methods. But it is just one field.
Regardless. If you have noise that propagates at the speed of light and gravity, then all the other groups are picking up part, or all your signals too. If you are tracking signals propagating at acoustic speeds and particle speeds then you should also be checking the speed of light and gravity signals - because there are almost always couplings - that show up in correlations.
And, if you are one of those rare people who also check for instantaneous signals (or ones that are billions of times the speed of light scale) then there are screens and checks for those too.
But here I am particularly asking for those "quantum" groups who find analog signals in their devices when they try to reduce the size, increase the frequency, lower the temperature -- and all the thing people are doing to get to "nano", "pico", "femto", "atto", "zepto". "yocto" scale phenomena.
Please update your notes on noise. Those strong millivolt, microvolt and nanovolt signals are just the start of many levels of tracking noise sources. If you have distributed sources it looks more like diffusion than shock waves or pulses. The signal from an earthquake is going to propagate at the speed of light and gravity, but it is going to have cubic kilometers of source. It is trackable, but it needs low cost detectors of high sensitivity and high sampling rates - then the arrays can image and track the seismic waves. That is just one of many hundreds of outstanding problems that need better detectors. I am hoping some of the groups who have been pushing hard to make "quantum device" will take a few moments to look at their noise seriously and think of the practical applications and problems of using those for imaging.
The signal at a superconducting gravimeter is about 95% sun moon tidal signal. That is about +/- 1000 nanometers per second squared (nm/s2) at one sample per second (sps). And the remaining 5% is from the atmosphere and nearby water and a tiny bit of magma. There will be the usual magnetic noise and electromagnetic noise from nanoHertz to GigaHertz. But some of it is gravitational - at least it shows up as a signal in a gravimeter or gradiometer or direct gravitational potential sensor (time dilation, Mossbauer, LIGO type detectors).
A "good" gravimeter array can image the local atmospheric density, flows, radiation field. That is a strong signal. You can convert gravitational signals to magnetic units by using B = 38.7083 g, where B is in Tesla and g is in meters/second^2. The earth field, 9.8 m/s2 comes to about 379 Tesla. That is why gravity is so fine grained and powerful. And why it is so hard to make strong magnets in the fluctuating earths gravitational field.
The tidal gravitational field is fairly smooth, but it can also be turbulent. You are just as likely to see "flow noise" than "sparks" or "shocks" or "pulses". And lots of slow drifts and sudden changes of levels. It is not hard, but requires care and effort.
I have been at this for several decades. I take this unusual step of asking "anyone with noise" to contact me. If you have shielded your device from electric field variations, and done some magnetic shielding and still getting drift and variations, then it is "gravitational".
I can tell you the rough size at the surface of the earth. A lot of the "kT" noise is gravitational flow noise. It is actually moving at the speed of light and gravity but you only see the net as a slow motion. The potential is smooth and has tiny gradients. You can see the gradients fairly easily. The "grain" is about one 7 millionth the mass of the electron and the size is picometers. The ultimate grain is not as small as the Planck scale, but on the order of 10^-24 meters. For practical things it is only necessary to work at 10^-18 scale. But use them all and you don't have to stop at boundaries.
Electrons have mass, charge and magnetic moment - so they pick up electric, electromagnetic, acoustic and gravitational noise (signals if you know where it comes from). Just as electron paramagnetic resonance has advantages of higher speeds and greater sensitivity, so too does any electron or hole based device have advantages for detection and characterization of fast and tiny signals. I spent several years checking - the camera electron (or hole) wells are sensitive enough to use for detecting gravitational variations - and there are plenty of tiny escape events to work with. The same for all the memory devices - they are just small floating islands of a few electrons each. Sorting out the noise in the memory chips will help shrink those down to single electron charge levels and below.
It is possible to image the atmosphere with gravitational arrays. Since I am lumping magnetic and gravitational fields together now, that means any combinations of "gravimeters" or "magnetometers" or "electromagnetic (from nanoHertz to PetaHertz or more). Moving sensors get a synthetic aperture advantage. So if someone would boost the GRACE type satellites to monitor the motion of electrons at Gsps rates we could get clear, real time images of the earths interior. Likewise moving sensor detectors arrays for volcanoes, ocean currents, density variations, magma and other things. The "moving" can be from seismic or natural vibrations, just measure it carefully for correlations and corrections. It jinks the position of the sensor so you can use subpixel methods. Deliberate movements are fine, but random but measured ones work too.
Richard Collins, Director, The Internet Foundation
I want to know how solar wind from a sun ( towards the earth) vary over a distance, specially during solar minimum period. Can you suggest some any related articles?
I'm looking for the original articles about magnetosphere physics that is written targeting the fundamentals. I'm highly interested in learning everything there is to know about the magnetosphere and how it interacts with the ionosphere.
I've recently been trying to run a transient simulation of a system with Fluent's solar ray tracing. I've been running into issues as to get proper results I need the simulation to go on for more than 48 hours. For some reason, after the first 24 hours of a Fluent simulation, the sun doesn't rise again. That is, from the 24th-hour onwards, solar flux is always 0. If anyone knows how to fix this let me know.
I understand that it should be possible to use a piece of software such as SolTrace to get the solar boundary conditions and then apply these to my transient simulations. Unfortunately, I cannot understand how to do this at all and I can't find any guidance online. I'm relatively new to Fluent so if someone could point me to a helpful source or give me an explanation I would be very grateful.
I'm also open to other solutions if people have had similar problems.
I am running a simulation of a system powered purely by energy from the sun. During the daytime, the results are as expected. During the night, I expect the system to still have a large amount of motion as there should be a decent amount of heat stored in the system. However, whenever I try to run a simulation spanning 24hr, I get a floating-point error when the sun sets. Before the error, I get some anomalous data where the temperatures and velocities are way too high (out by 4 orders of magnitude or more). I really don't understand what the issue is here. When the sun sets shouldn't the solar loading just stop? Shouldn't the system just slowly use up its remaining energy until the sun rises again? Is it possible that the radiation is falling on the base of my geometry?
I think that I am misunderstanding something about the solar loading as it is this that triggers the issue. In my attempt to troubleshoot, I set up a system that was definitely stable and well defined without the solar load. Then, when a solar load was applied and I ran it in a 24hr transient simulation I faced the same issue.
Any help, advice, or a point in the right direction would be appreciated.
My main goal is to use Neural Networks to forecast Sunspot Numbers. Requesting the option of ANN or RNN seems simple enough. However, which is best to learn and utilize for a complete beginner? If there is a GitHub repository for similar Space Science topics based on Neural Networks, please link me to it. I'd be extremely appreciative.
Parker solar probe is providing data from different encounters. If we plot data over a distance (for eg: from 0.5 au to 0.17 au), it shows, towards the sun, interplanetary magnetic field increases. It has also positive correlation with solar wind density and temperature, however, slightly weak correlation was obtained for solar wind speed. I want to learn how solar wind parameters vary over a distance, and a physics associated with it. Need your suggestion (please suggest me some good articles, if available). Thank you.
I am working on a project to calculate solar radiation in urban area. The tool that I am using is the r.sun module in GRASS GIS. For running this module, the user should input the time-step interval. How do we determine this parameter? Are there any specific criteria for selecting the time step besides the variation of the sun position?
IS That okay, If I injection Paraffin and Sun Flower Oil as it's to GC-MS, or this may be damage the column?
If okay to inject, How can inject the sample look like as it's or must be diluted in EtOH?
Thanks in advance!
I know about Mansur equation
Where: EE (l) – erythemal effect spectrum; I (l) – solar intensity spectrum; Abs (l)- absorbance of sunscreen product ; CF – correction factor (= 10). my query is regarding correction factor .
from the literature what i understood is that CF – correction factor (= 10). It was determined so that a standard sunscreen formulation containg 8%homosalate presented a SPF value of 4, determined by UVspectrophotometry (Mansur et al., 1986).
My formulation of sunscreen lotion contains only 1% of sunprotecting active ingredient. In this case should i change the correction factor accordingly ??
The sun’s UV rays help your body make this nutrient, which is important for your bones, blood cells, and immune system. It also helps you take in and use certain minerals, like calcium and phosphorus. And while most people get enough vitamin D from food, children who don’t can get rickets, which softens and weakens their bones.
Moderate amounts of sun over your lifetime, especially in your teen and young adult years, might make you less likely to have problems seeing things at a distance (nearsightedness). But too much direct sunlight can hurt your eyes. It can lead to blurred vision and raise your chances of cataracts.
This also raises your chances of skin cancer. If you do it before age 35, you’re 60% more likely to get melanoma, the most serious form. Even one session can raise your odds of melanoma by 20% and other types by as much as 65%. If you want that all-over body tan, tanning lotions might be an option. Most are safe, but they usually don’t have sunscreen in them, so don’t forget to put that on as well.
This may be a very naive question, but please bear with me.
I have noticed that many solar simulators used in papers on photocatalysis and solar evaporation have xenon lamps that have a power rating of 450 watts for example.
How then does it achieve an irradiance of 1000W/m2? Do these solar simulators have utilize lenses to increase the intensity?
We see an object when the light comes to our eye from that object. For a bulb or sun when we look direct we see that bulb or the sun. But when light is put on some other surface we see only that surface, not the source bulb or sun. So what property does the light have? Why after reflection light loses the previous source image? Is that source image is actually lost after reflection? Or the light carries out everything but our present technology is unable to detect it?
Sunrises that occur usually every 11 years cause specific climate changes and weather anomalies on Earth. The effect of these solar suns is also the emerging effect of El Ninio in the oceans, changes and increasing the activity of water currents in the oceans.
Some research subjects of this issue relate the solstice of solar activity with human activity suggesting that in these years more dramatic political, economic and other events occurred.
On the other hand, paradoxically, in the last dozen or so years, the activity of Sun decreased. Despite the declining solar activity, the greenhouse effect on Earth is accelerating, and the ozone hole is expanding what can adversely affect human health and change natural ecosystems.
Do you know publications that describe this type of correlation? If so, please link to these publications.
In the light of the above, encouraging discussion, I turn to you with the following question: Does anyone of you investigate the question of the relationship of solar solstices to the events of the development of human civilization on Earth?
Please, answer, comments. I invite you to the discussion.
I wish you the best in New Year 2019. Best wishes