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# Tag Info

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The NASA has a lot of data on eclipses. I've pulled the table for the 21st century in Excel. There are 228 eclipses of which 85 are total. The durations below are for the totality phase. The duration of today's eclipse is 103 minutes. The average duration is 68.7 minutes. The duration of the next total eclipse, January 21st, 2019 is 62 minutes. The shortest ...

15

It would look like this (actual picture of the Earth, seen from the Moon, during a lunar eclipse): Link to full page: http://apod.nasa.gov/apod/ap140407.html The Earth would appear surrounded by a bright ring, even though the Sun is completely hidden behind it. The ring is sunlight refracted through the atmosphere. It's basically all the sunrises and ...

12

The NASA sites have some very useful resources for this I will list them below: Lunar Eclipses This Link has an index for all lunar eclipses from -1999 to +3000, predominantly a statistics page but also has this page that contains how to calculate when lunar eclipses are. There is more than one formula depending on which time frame you are trying to look ...

12

On any given day, you see the moon rise in the east and (apparently) travel across the sky from your left to the right; therefore, you would assume (incorrectly) that the leading edge of the moon's movement must be to the right. That is not correct. The apparent motion you are seeing is predominantly from the Earth's ~24 hour rotation. But the orbit of ...

10

It would look like a solar eclipse! What happens is that Earth gets in the way between the Sun and the Moon. From Earth we see the Moon disappear, from the Moon one would see the Sun disappear. Earth is fix on the Moon's sky, because the Moon always turns the same side towards Earth. Earth as seen from the Moon has phases, like the Moon has when seen from ...

9

Solar and lunar eclipses occur about equally often - between two and four times per year. However, when you do not intentionally travel around the world chasing solar eclipses, you are more likely to observe more lunar eclipses. The reason is that solar eclipses can only be observed from a comparatively small area while lunar eclipses can be observed from ...

9

Calculation of solar eclipses can be done using Besselian elements. The basic idea is to compute the motion of the Moon's shadow on a plane that crosses the Earth's center. Then, the shadow cone of the Moon can be projected on the Earth surface. The Besselian elements are the following: X and Y: the coordinates of the center of the shadow in the ...

9

The NASA NASA Five Millenium Catalog of Lunar Eclipse says that the longest total lunar eclipse was 106.6 minutes or 1 hr 46.6 minutes. The link for this century shows that the July 27th eclipse is indeed the longest at 1hr 43 minutes (rounding up). So it is definitely up towards the maximum length at ~96% of the longest known. Two times can be given for ...

7

No, not all total lunar eclipses will turn the Moon deep red. Most of them do, but not all. If you were standing on the Moon during the eclipse, you'd see the Earth passing in front of, and obscuring, the Sun. But the Earth will never become fully dark, even when the Sun is fully covered. A bright ring will always surround the Earth. Why? That ring is ...

6

It is great that you have an interest in astronomy. Unfortunately, the UK will be on the wrong side of the Earth to see the lunar eclipse on April 15. If you you want to experiment with various places on earth that will see it, and what they will see, get a planetarium application like Stellarium or SkySafari or TheSkyX. A lunar eclipse is always easy to ...

5

What can you say but "Wow..." http://www.space.com/32245-total-solar-eclipse-video-dscovr.html "The moon's dark shadow travels across Earth's face in spectacular new views of Tuesday's (March 8) [2016] total solar eclipse captured by a satellite in deep space." I'm sorry my answer is off by about 700,000 miles compared to what you asked :) I'm fairly ...

5

As Wayfaring Stranger's answer says, during a lunar eclipse seen from Earth, an observer on the Moon would see a solar eclipse. Earth is about 4 times the apparent diameter of the Sun. You can see a photo of such an eclipse, taken by Japan's Kaguya spacecraft in lunar orbit, here. During a solar eclipse seen from Earth, an observer on the Moon would see the ...

5

From the way you have formulated your question, it seems to me that you are aware of the light diffusive process named Rayleigh Scattering and why it explains the various tints and colours of the sky depending on the Sun position. Other readers can refer to https://en.m.wikipedia.org/wiki/Rayleigh_scattering. We are used to our atmosphere and as such often ...

5

'P' is the penumbra, the zone where the Earth blocks some, but not all, of the Sun's light from reaching the Moon. 'U' is the umbra, the zone where the Earth blocks all of the light from the Sun (see this primer). As the Moon moves across the two zones then you will get various times as the Moon touches those zones. So P1 is where the Moon just starts to ...

5

We'll need the angular diameter of the Sun: 31.6-32.7 arcminutes; the Moon's is between 29.3 and 34.1 arcminutes (found on Wikipedia). The solar eclipse case is 0 degrees; it can only be an eclipse if the Moon is touching the Sun. In that case, their centers are at most (32.7 + 34.1) / 2 = 33.4 arcminutes apart. A lunar eclipse would occur if the Sun and ...

4

A lunar eclipse on earth is a solar eclipse on the moon. The earth takes up 2° of sky from the lunar surface (vs 0.5°), so you'd see less corona in your space suit. The moon's speed through earth's shadow is only about 1 km per second, so you'd have up to 107 minutes of totality. What with earth's atmosphere, I doubt you'd see much in the way of Baily's ...

4

The Lagrangian point $L_2$ is very close to the most distant point from Earth with an umbra. $L_2$ is like the radius of the Hill sphere at $r=a\sqrt[3]{\frac{m}{3M}}$ for circular orbits, with $m$ the mass of Earth, $M$ the mass of the Sun, and $a$ the distance Earth-Sun. The ratio $\frac{m}{3M}$ of the Earth and the triple mass of the Sun is almost exactly ...

4

If the Earth were alone in space and the hypothetical moon had negligible mass, you can calculate the distance at which the period would be one year using: $$a = \left( \frac{GM_E T^2} {4 \pi^2} \right)^{1/3}$$ where $GM_E$ is the standard gravitational parameter of the Earth (about 3.9860E+14 m^3/s^2) and $T$ is the period (about 365.2564 x 24 x 3600 ...

4

astrosnapper already explained the chart and the Us and Ps, so I'm going to focus on the map. The map shows you which phase of the eclipse is visible from where. For example Mauritius gets to see the whole eclipse while North America is out of luck and doesn't get to see any. From my vantage point in Germany I should have been able to see from somewhere ...

3

Frankly, four bodies do not periodically line up, even if the orbits are planar, unless there exist a common multiplum. Because all your periods are integers, that holds, but be aware that your double alignments, like the double solar eclipse or double lunar eclipse is not periodic if one of the periods does not exactly follow that integer system. (so it ...

3

This was clouds. Eclipses occur at full moon, not last quarter. Eclipses take several hours as the moon traverses the Earth's shadow, not a few minutes. Eclipses don't look like the moon becoming a gleaming point of light. In a lunar eclipse the moon becomes a copper colour, as it is illuminated by red light that has passed round the Earth, through our ...

3

During a lunar eclipse on Earth, the Sun would be eclipsed by the Earth as seen from the Moon: $\hspace{3cm}$ What this animation does not show is the corona around the Sun (which would be partially visible when the sun has been occulted) and the reddish ring of light that would encircle the Earth due to the sunlight refracted by the atmosphere of the ...

3

Yeah, you'll see earth as all dark, if it is total lunar eclipse. In a Lunar eclipse earth comes in between the sun and the moon. Because of this, the sun rays don't reach the surface of moon. Now answer to your question: As earth's sunward side is blocking light the other side will be darker. As you are standing towards shadowed side of earth, you ...

3

A lunar eclipse occurs when a full moon occurs at the same time as a lunar node (when the moon crosses the ecliptic - the plane of the Earth's orbit around the sun) The time between full moons is 29.53... days (although it varies slightly due to the moon's orbit not being circular) This is the synodic month. The time between nodes is 27.21... days. This is ...

3

What causes the moon to be red is our own atmosphere. It's the same effect that causes a sunset to be red. As the sun nears the horizon, the amount of air that we're looking through increases - and with it everything in the air such as dust, pollution, humidity, etc.... If you look at the moon near the horizon, you'll notice it is significantly yellower/...

3

Nothing so romantic as the universe being fair. The path of the moon is tilted by about 5 degrees from the path of the sun. but twice a month the moon must cross the path of the sun. When this moment coincides exactly with full moon there is a lunar eclipse. Since the sun is on the opposite side of the Earth, lunar eclipses are only visible during the ...

3

Because we are standing on a rotating globe. We are changing direction as the Earth spins. This appears exaggerated in the video as the horizon is not visible, so there is no way of seeing how the camera was rotated to view the moon as the eclipse progressed. Relative to the stars, the moon appears to enter the Earth's shadow from one side and leave it ...

2

Pretty most all lunar eclipses will turn the moon red like that. The amount of redness does vary, and sometimes so little light gets to the sun it is almost completely dark. However the redness is so typical of a lunar eclipse that NASA describes it as a "characteristic orange-red color". That link has a neat table with a categorization of the colour ranges. ...

2

Every new moon would be a total solar eclipse. Incorrect. Even if the Earth had no axial tilt and the Moon had an equatorial orbit, that doesn't mean that every new moon would be a total solar eclipse. Yes, the moon would always generate some kind of an eclipse at every new moon, but it's orbit shape hasn't changed -- it's still an ellipse. It's ...

2

May, or may not. No. Q1: A formula: yes, a simple formula: no. Q2: Not for each point on Earth. This is e.g. due to different distance quotients. Q3: Depends on distances, sizes, angular velocities, position on Earth. Q4: Yes, but it's different for each point, not just by latitude. Even at the equator, there may exist points with, and points without ...

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