Questions tagged [eclipse]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0 votes
1 answer
60 views

What's the time window for total and narrow eclipses?

Because of the tidal effect angular momentum is transmitted from Earth rotation to the Moons orbit around Earth. This means that perfect eclipses only has occured during a certain time window. Can ...
user avatar
  • 493
19 votes
3 answers
2k views

Why is it so dark during a solar eclipse?

At a total solar eclipse the sun is barely covered, like right after sunset. So why is it much darker than right after sunset (which allows us to see the corona)?
user avatar
7 votes
2 answers
691 views

The effect of gravitational lensing during the lunar eclipse

During the lunar eclipse, the Moon turns into bloody colour while the shadow of the Earth is casting over the lunar surface. The red hue can be explained by means of the refraction of light and ...
user avatar
10 votes
3 answers
1k views

Proof/explanation that Sun is bigger and more distant from Earth than Moon is, Middle Age technology allowed only

If I was living in the Middle Ages, how can someone prove or at least explain to me in a simple way that the Sun is bigger and more far from Earth than the Moon? Can a parallax be used for it? $$\text{...
user avatar
  • 191
2 votes
1 answer
54 views

Is a 3 body system with a permanent eclipse possible and stable?

Is it possible to have a star, planet and moon where the moon orbits the planet in the opposite direction with the same period of the planet orbiting the star? So that there would be a never-ending ...
user avatar
  • 184
2 votes
1 answer
62 views

Why Earth is viewed crescent from moon when the Earth is experiencing total solar eclipse?

Suppose a person, let's say Neil, is on moon and Earth is experiencing a total solar eclipse so how should Neil perceive the Earth? This is also a question from KVPY (5/11/2017) question no. 22. as ...
user avatar
2 votes
1 answer
35 views

Harmful Radiation When a Thinly-Veiled but Evident Sun is Directly Viewed Under Haze or Cloud Cover

When it is hazy or overcast with many thin fast-moving clouds, the sun sometimes appears faintly though the cover---making it possible to be observed without any discomfort. In fact, one could easily ...
user avatar
0 votes
1 answer
136 views

Fraunhofer lines during an eclipse

I know that Fraunhofer lines are certain wavelengths in the Sun's spectrum that are 'missing' because of absorption at the chromosphere. In other words, they are 'dark'. But my book clearly states ...
user avatar
-1 votes
2 answers
91 views

What is the logic behind the Eddington expedition that proved Einstein's general theory of relativity?

The Eddington expedition in 1919 proved Einstein's general theory of relativity. [Eddington] argued that the deflection, or bending, of light by the Sun’s gravity could be measured... because ...
user avatar
  • 71
0 votes
1 answer
27 views

Definition of eclipsing binaries?

In the second minimum (the 3rd step) there is a smaller decrease in light intensity. For this to happen, wouldn't you need to be looking at the plane of orbit from above rather than directly along the ...
user avatar
  • 695
1 vote
1 answer
67 views

Why eclipses are not periodic?

From mathematics, we know that if any two or more functions are periodic in nature, their combination would also be periodic in nature with some exceptions. Since motions of the sun, the moon and the ...
user avatar
2 votes
1 answer
71 views

What is the derivation of this formula for eclipsed flux?

From my lecture notes: Planetary Transit Searches If a planetary system’s orbital plane lies along our line of sight, planets will from time to time pass in front of their star, absorbing some of the ...
user avatar
  • 61
1 vote
2 answers
145 views

Why do we have eclipses if the Earth's orbit around the Sun and the Moon's orbit around the Earth aren't in the same plane?

We know that eclipse is when the Sun, the Earth and the Moon align in a straight line. How do they do this align if their orbit planes aren't in the same angle?
user avatar
20 votes
7 answers
5k views

What is a simple argument to prove that the stars in the sky are further away from the Earth than the Moon?

How do we know, without using modern equipment, that the stars are further away than the moon in the night sky? Further, is there a simple and actionable argument to prove that this is indeed the case?...
user avatar
  • 2,340
2 votes
1 answer
75 views

Measuring the solar system's speed through ether with the help of an eclipse

In A.P. French's Special Relativity, the author said, Jupiter has a period of $12$ terrestrial years, and so in half a terrestrial year, while the earth moves from $A$ to $B$ (Fig. $2$-$7$), ...
user avatar
  • 1,202
1 vote
1 answer
192 views

What are the objects that are like a crescent and blue sphere? (while taking shots of a solar eclipse)

This is the picture I have took while the solar eclipse. What are the objects that are like a crescent and blue sphere? I know that such (rays) appear whenever we photograph the Sun but what is the ...
user avatar
4 votes
3 answers
472 views

Why does the shadow of Io on Jupiter look so big?

It has been reported this week[0] that the following image by Kevin Gill is the shadow of Io crossing Jupiter. Why is the shadow so large? My intuition is that Io is much smaller than Jupiter so ...
user avatar
  • 231
0 votes
1 answer
70 views

Gravitional bending of light in an eclipse of the sun, formation of an Einstein ring

Has it been observed that at Moon occultation of the Sun the bending of the light beam arriving from a distant stelar object behind the Sun is isotropic or the rotation of the Sun slightly modifies ...
user avatar
0 votes
1 answer
47 views

Ever looming shadow

If I'm not mistaken the reason the moon eclipses the sun is because the ratio of distance to size, in regards to the moon and sun, is 1:1. And is it not also true that the reason we only ever see one ...
user avatar
4 votes
3 answers
180 views

Can we determine the date just from sky observations?

Assuming everyone "freezes" for several thousand years. Then everyone unfreezes at the same time. Could we tell how much time passed based on sky observations without fancy telescopes? (Just started ...
user avatar
  • 185
0 votes
2 answers
280 views

Confusion about a claim in the "Brief History of Time" by Hawking

In the first chapter, while talking about how Aristotle was able to conclude that the Earth is spherical, Hawking says that had the Earth been a flat disk the shadow of the on the Earth on the moon ...
user avatar
  • 333
1 vote
1 answer
60 views

What does the image from Eddington on gravitational light bending really show?

There is a famous image that one often sees taken by Eddington during the 1919 solar eclipse illustrating gravitational light bending as predicted by Einstein. Can someone explain what exactly is ...
user avatar
  • 1,547
2 votes
1 answer
420 views

Why does the red light from Sun bend towards the moon during the total lunar eclipse?

During the total lunar eclipse the earth, moon and the sun are in perfect alignment so that the moon is within the umbral shadow of the earth. However, instead of turning invisible the moon actually ...
user avatar
1 vote
1 answer
46 views

Lunar eclipse redness not visible through telescope?

I watched the total lunar eclipse on January 20-21 in North America. Looking at it with my eyeballs it appeared red. This is due to Rayleigh Scattering. When I looked at the eclipse through binoculars ...
user avatar
  • 111
3 votes
3 answers
233 views

Shift of the apparent position of stars during the total solar eclipse

One of the evidence supporting the General Relativity is a shift of the apparent position of the stars during the total solar eclipse. I would like to know if the shift can be explained by other ...
user avatar
  • 163
1 vote
1 answer
572 views

What is the diameter size of the umbra shadow cone of the Earth when the Moon passes through it on a lunar eclipse?

I am sure this varies given the distance from moon to earth varies, but a range would be sufficient. I am trying to explain to a flat earther how there is not a lunar eclipse every full moon. My ...
user avatar
1 vote
0 answers
109 views

Why does the moon becomes red instead blue during an lunar eclipse?

While observing an lunar eclipse, I noticed that the moon is first covered by a distinct strip of blue light, to then at its apogee, the moon is completed covered by a red light. I understand that the ...
user avatar
1 vote
1 answer
368 views

What does cause the 360 degree "sunset" during a total eclipse?

On August 21, 2017, I had the pleasure of witnessing a total solar eclipse. One of the main attractions was the 360 degree "sunset". But I am now wondering what does cause this phenomenon to happen ...
user avatar
3 votes
0 answers
126 views

Viewing totality though an unfiltered telescope [closed]

DISCLAIMER: This question is for informational purposes only and the ensuing discussion must not be construed as safety advice. There seems to be a consensus among experts that partial eclipse should ...
user avatar
0 votes
1 answer
380 views

why do total solar eclipses vary in length?

Quoting https://www.mnn.com/earth-matters/space/blogs/why-2024-total-solar-eclipse-may-outshine-2017, For the 2017 eclipse, the duration of totality will last between 20 seconds (over Kansas City,...
user avatar
  • 167
-1 votes
1 answer
63 views

Are there different defintions/ interpretations of the phrase "total solar eclipse"? [closed]

One total solar eclipse was visible in the United States on 08 June 1918. Another on 26 February 1979. Again, there was one just the other day (for those that might not have noticed). Links are ...
user avatar
2 votes
1 answer
2k views

Is looking at an eclipse worse than looking at the sun? [duplicate]

I understand why looking at the sun is bad. I also understand that looking at the eclipse is bad. Is it more dangerous to glance at an eclipse than the sun, assuming you avert your eyes right very ...
user avatar
0 votes
1 answer
58 views

What speed should I maintain on land or in the air in order to experience the whole path of total solar eclipse?

What speed should I maintain on land or in the air in order to experience the total path of total solar eclipse? And What other factors are taken into account for calculating that speed? For e.g. ...
user avatar
1 vote
1 answer
718 views

How does the Sun burn a crescent shaped scar in your eyes during a solar eclipse?

I was listening to NPR this morning and a man talking about the solar eclipse said that you cannot look at even a sliver of the sun because it could still damage your eyes. He noted he's even had ...
user avatar
  • 141
48 votes
3 answers
26k views

Why aren't 100% UV blocked sunglasses safe to view an eclipse with?

I am not planning on staring into the sun during an eclipse or any other time. I have been reading about how no variety of regular sunglasses are safe enough to view the eclipse with. I'm not talking ...
user avatar
  • 453
4 votes
1 answer
124 views

Total eclipses becoming rare soon?

Given that the moon is receding from the earth and that the average angular size of the moon is approximately equal to the angular size of the sun at the moment, what is the current rate at which ...
user avatar
-2 votes
1 answer
2k views

Why can I look at the sun with my sunglasses but not at the solar eclipse?

Is the problem with seeing an eclipse that you have a sudden change between penumbra and regular sun? If that's the case, why can I look to the sun with my sunglasses on but I can't do it in an ...
user avatar
2 votes
2 answers
3k views

Can two polarized glass filters held at near 90° orientation serve as safe eclipse glasses? [closed]

Using two polarized filters to block all (?) light is a common classroom demonstration. With the imminent north American total eclipse, the media has been pushing eclipse glasses and emphasizing the ...
user avatar
2 votes
3 answers
299 views

Solar Eclipse Path of Totality

Every depiction I have seen shows the Eclipse path of totality travel Eastward from Oregon. Why Doesn't the path travel Westward from South Carolina as the Earth rotates Eastward? Shouldn't the ...
user avatar
1 vote
0 answers
297 views

What are eclipse glasses made of? [closed]

What is the principle of eclipse glasses? Are they just high optical density plastic, or do they do something fancier? Could I make my own by taping ND filters into cardboard? I tried Googling ...
user avatar
  • 3,412
1 vote
2 answers
1k views

Why isn't there an eclipse every month? [duplicate]

Given that eclipses occur, why aren't they more regular? If the sun and the moon are in the same plane, shouldn't the moon transect the line from the earth to the sun every month? I guess order of ...
user avatar
1 vote
0 answers
22 views

What are ShadowBands during SolarEclipse and how can it be reproduced?

I recently got to know about different phases of a solar eclipse and its impact on Earth and its living creatures.., but one of the most interesting and not well explained phenomenon is the ...
user avatar
  • 11
3 votes
1 answer
913 views

Traveling in the umbra of a solar eclipse

On August 21 this year, parts of the United States will experience a total solar eclipse, as many of you probably know. Say that I am in an airplane at the center of the umbra of the moon when it ...
user avatar
  • 154
0 votes
1 answer
44 views

Time Desynchronization (gravitational)? What if an eclipse was synchro between 2 altitudes on earth 1 million years before and is still synchro today?

2 events watched from 2 altitudes. Imagine an eclipse of the sun happens 1 milion years before (event 1) and it happens once more (event 2). (2 eclipses with 1 milion year interval watched from 2 ...
user avatar
  • 113
2 votes
1 answer
172 views

2017 solar eclipse: why are these two maximal eclipse points different?

referring to this guide, there is a point in southern Illinois that has the longest duration eclipse and a point in western Kentucky where the eclipse is the "greatest". the first i understand, the ...
user avatar
63 votes
4 answers
7k views

Why does the sun have to be nearly fully covered to notice any darkening in an eclipse?

I was looking at eclipse footage and I noticed that it doesn't get any noticeably darker until the very end when it suddenly all the light is gone. As the moon blocks out the Sun, I would expect that ...
user avatar
0 votes
0 answers
220 views

Can we calculate the point on Earth nearest to the Moon?

We have the ability to calculate the Moon's orbit in order to predict Lunar and Solar eclipses precisely. Using our known calculations of the Moon's orbits, can we calculate the closest point (city ...
user avatar
1 vote
1 answer
289 views

Does solar eclipse have impact over increase of earth's temperature?

Does a solar eclipse have an impact on global temperature? Wired theory : When I jump, does the Earth recoil? Yes, the Earth has to move in some way for momentum to be conserved. However, since ...
user avatar
-1 votes
1 answer
110 views

How could a solar eclipse cause my light bulb to explode? [closed]

Any explanation to this? as it happened right during the phase of eclipse or is it just coincident? I had just finished my breakfast and on the way to go outside to watch the eclipse and before it ...
user avatar
  • 37
2 votes
2 answers
3k views

Why are Lunar Eclipse more common than Solar Eclipse?

Why are Lunar Eclipse more common than Solar Eclipse? Chapter from Light My thoughts; Eclipse can only occur at new moon and moon orbit is inclined at an angle of about 5 degrees to the earth's ...
user avatar