- An eclipse path
is the path of the
Moon's umbra
on the Earth's surface during
a total solar eclipse or
the path of the annularity region (caused by the
Moon) over said surface during an
annular solar eclipse.
The width of the path is set by region of totality for
total solar eclipses
and by the region where the annulus
of the Sun can be seen for
annular solar eclipses.
- Mainly because of the
axial tilt
Earth's axis
from the
ecliptic pole,
the eclipse paths
are curved as the image shows:
i.e., curved with respect to straight lines of
latitude
on a Mercator projection map.
- Because the Moon
can be at any distance up to an
Earth's radius
above or below the ecliptic plane
during an eclipse season,
eclipse paths can be at any
latitude, even at the
Earth's poles.
If counterfactually
the Moon's orbit was in
the ecliptic plane,
we would have
total/annular solar eclipses
every new moon,
the eclipse paths
would be confined to the tropics:
i.e, ∼ 23.4 south latitude
to ∼ 23.4 north latitude.
- Note that the
eclipse paths
are very wide in
Arctic
and Antarctic.
This is probably for two reasons.
First and certainly, Mercator projection
stetches out all lengths as one moves away from the
equator.
Second and probably, the umbra
gets stretched out when landing on the more tilted surfaces that
are far from the equator.
- A solar eclipse region
(umbra and
penumbra)
sweeps basically eastward in
space.
The Earth also turns
eastward.
In this horse race,
the solar eclipse region
is faster, and so it
moves mainly eastward on the
surface of the Earth.
So the umbra on an
eclipse path moves
mainly eastward on the
surface of the Earth.
Yours truly recalls from somewhere that the
umbra on/over the
Earth for ∼ 3.5 h at most???.
- On the Earth's surface,
the lunar umbra
or eclipse path has
a maximum width is 267 km
(see Wikipedia: Solar eclipse: Path)
and the approximate maximum
east-west
extend is probably a bit less.
The longest totality for any one place is 7 m, 32 s
(see Wikipedia: Solar eclipse:
Occurrence and cycles;
Wikipedia: Solar eclipse: Path).
- The fiducial
minimum eclipse path
velocity is
the mean orbital velocity
of the Moon
moving approximately eastward
in space minus
the tangential speed
of a point on the
Earth's equator
(which is moving exactly eastward
at the maximum Earth surface
velocity):
v = 1.022 - 0.46511 = 0.5569 km/s = 33.41 km/m = 2005 km/h .
The actual minimum
eclipse path
velocity varies a bit depending
on various factors and is more typically ∼ 1700 km/h
(see Wikipedia:
Solar eclipse: Occurrence and cycles).
The maximum
fiducial
minimum eclipse path
velocity
occurs at the Earth's poles
where the Earty is NOT rotating at all.
The value is, of course 1.022 km/s = 3679 km/h.
- As Image 2 shows, there was a good
annular solar eclipse
whipping through the western USA
on 2023 Oct14.
This annular solar eclipse
is the annular
solar eclipse of 2023oct14 Saturday.
So you'll have to whip up to
Elko, Nevada to see
the annularity.
For the detail of the
annular solar eclipse
in Elko, Nevada
and Las Vegas, Nevada,
see, respectively,
Time&Date:
Eclipses in Elko, NV, USA
and Time&Date:
Eclipses in Las Vegas, NV, USA.
- Also as Image 2 shows,
there was good total solar eclipse
whipping across the
USA and
over Port Colborne, Ontario
(yours truly's hometown)
on 2024 Apr08.
This is the total solar eclipse
is the
total solar eclipse of
2024apr08 Monday.
Credit/Permission: