What is an Aitoff plot?

What is an Aitoff plot?

Description. The Aitoff projection is a modified azimuthal projection. It is a compromise projection whose graticule takes the form of an ellipse. This projection is appropriate for small-scale mapping of the world. It was developed by Russian cartographer David A.

What is Aitoff projection used for?

Aitoff Projection The Aitoff equal area projection was used to provide photometrically correct maps of the entire celestial sphere for the Low-Resolution All-Sky Maps. Galactic coordinates were chosen as a convenient and natural coordinate system.

What is a hammer map used for?

It is used most often for whole-world maps. In this projection, the central meridian is depicted as a straight line half the length of the Equator. Other meridians are depicted as complex curves, unequally spaced along the Equator and concave toward the central meridian. The Equator is straight.

What is a Mollweide projection map?

The Mollweide projection is an equal-area pseudocylindrical map projection displaying the world in a form of an ellipse with axes in a 2:1 ratio. It is also known as Babinet, elliptical, homolographic, or homalographic projection. The Mollweide map projection is shown centered on Greenwich.

Who uses the hammer projection?

Ernst von Hammer developed it in 1892. It is used most often for whole-world maps. In this projection, the central meridian is depicted as a straight line half the length of the Equator. Other meridians are depicted as complex curves, unequally spaced along the Equator and concave toward the central meridian.

What is a Winkel Tripel projection map?

The Winkel Tripel is a compromise modified azimuthal projection for world maps. It is an arithmetic mean of projected coordinates of Aitoff and equidistant cylindrical projections. The projection is known to have one of the lowest mean scale and area distortions among compromise projections for small-scale mapping.

How many map projections are there?

This group of map projections can be classified into three types: Gnomonic projection, Stereographic projection and Orthographic projection.

What does an interrupted map do?

In map projections, an interruption is any place where the globe has been split. All map projections are interrupted at at least one point. Typical world maps are interrupted along an entire meridian. In that typical case, the interruption forms an east/west boundary, even though the globe has no boundaries.

What does a Goode map show?

The Goode homolosine projection (or interrupted Goode’s homolosine projection) is a pseudo- cylindrical, equal-area, composite map projection used for world maps. Normally it is presented with multiple interruptions. Its equal-area property makes it useful for presenting spatial distribution of phenomena.

Why do people use the Mollweide?

Mollweide projection is commonly used in small-scale mapping and thematic maps to illustrate accurate area characteristics. Thus, it is used mainly on maps that require accurate areas as opposed to those requiring accurate shapes and angles. It can also be used to show distributions of global data.

Why is Mollweide projection called elliptical?

In 1805, Karl Brandan Mollweide (1774–1825) announced an equal-area world map projection that is aesthetically more pleasing than the sinusoidal because the world is placed in an ellipse with axes in a 2:1 ratio and all the meridians are equally spaced semiellipses.

What is a Goodes map?

The Goode homolosine projection (or interrupted Goode homolosine projection) is a pseudocylindrical, equal-area, composite map projection used for world maps. Normally it is presented with multiple interruptions. Its equal-area property makes it useful for presenting spatial distribution of phenomena.

What is a hammer Aitoff map?

The Hammer-Aitoff Projection. This map projection is an equal-area map projection which displays the world on an ellipse. However, it is completely unlike the Mollweide projection. In the conventional case, the parallels are curved, and there is no stretching at the center of the map.

What is the Aitoff projection?

This projection was created by David Aitoff in 1889. It is a modification of the Equidistant Azimuthal projection. The Aitoff projection inspired the similar Hammer projection, which is equal area. This implementation of the Aitoff projection is applicable only for coordinates that are referenced to a sphere.

How many Hammer-Aitoff projections were used in the Atlantic Ocean?

Many years later, he used three Hammer-Aitoff projections, one for each of the Pacific, Atlantic, and Indian oceans, combining the three lobes to make a map of the World Ocean. I illustrate here the three component projections, without attempting to stretch the map to fit them together as he did:

What is the difference between Aitoff’s projection and Winkel tripel projection?

While the equal-area projection is in relatively common use, Aitoff’s original projection is hardly ever seen; only now that the Winkel Tripel projection is also in wide use has it become necessary to even mention the actual Aitoff projection to describe how the Winkel Tripel is constructed.