Angular Diameter

The apparent size or angular diameter refers to an object’s size as viewed from a specified place. It is the object’s visual diameter as determined from an angle. This is known as a visual angle. It is the visual diameter perspective projection diameter of an object. In this case the object is set on a plane through its middle that is perpendicular to the view direction.

Apparent Sizes of the Earth and Sun

The apparent size of the orbit of the Earth round the Sun is 2” (two arcseconds). This is from a one parsec distance. The apparent size of the Sun is 0.03”, and the Earth 0.0003”. This is at a light year distance. The Sun 0.03” apparent size is similar to that of an individual at a distance of the Earth’s diameter.

Apparent Sizes of Celestial Bodies

These angular sizes are based on views on Earth. For the Sun it is 31.6’ – 32.7’; for the Moon it is 29.3’ – 34.1’ and for Venus it is 9.565” – 66.012”. The angular diameter of Jupiter is 29.800” – 50.115” and for Saturn it is 14.991” – 20.790”. For Mars the apparent size is 3.492” – 25.113”. The apparent size of Mercury is 4.535” – 13.019”.

The apparent size of Uranus is 3.340” – 4.084”. Neptune’s apparent size is 2.179” – 2.373”. Ceres is 0.330” – 0.840”. The apparent size of Vesta is 0.20” – 0.64”. For Proxima Centauri it is 0.001”. For Deneb it is 0.002”. The apparent size of Altair is 0.003”.

The apparent size of Sirius is 0.005936” and for Canopus it is 0.006”. For Alpha Centauri A, it is 0.007” and for Alphard it is 0.00909”. The apparent size of Eris is 0.00909”. Betelgeuse is 0.049” – 0.060”; R Doradus has an apparent size of 0.052” – 0.062” and for Pluto it is 0.063” – 0.115”.

More about the Sun Apparent Size

The figures given indicate the Sun apparent size is 250,000 times compared to Sirius. The Sun apparent size is 250,000 compared to Alpha Centauri A. The Sun is 40 million times as bright. The Sun’s apparent size is almost equal to the Moon in this respect. Objects that are not circular are given two diameter measurements: Minor and Major Diameters. For instance, the Small Magellanic Cloud has a 5 degree 20’ x 3 degree 5’ visual diameter.

Angular diameter measurements may not be the same as the object’s physical diameter because of foreshortening. The figures are the same for a disc shaped object however.

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Diamond Engagement Ring Sizes

Diamond Engagement Ring Sizes

When choosing diamond engagement ring sizes, there are actually two sizes that you need to consider: the size of the diamond and the size of the actual ring. Diamond carats come in less than a carat to 2.75 carats on average; while ring sizes can be anywhere from one inch up to sixteen inches.So you’re ready to pop the question. But before you can do so, you must of course have the perfect engagement ring that will have her squealing and crying at the same time.

How do you go about choosing the right diamond engagement ring sizes that will fit her finger perfectly? Since you can’t ask your girlfriend to go with when you when shopping for an engagement ring, there are a few things that you can do to help you pick the right diamond engagement ring.

A few things to consider are:

Diamond Size

While you may want to splurge and immediately think that bigger is better; this is not always the case. Choosing diamond sizes should actually be based more on her lifestyle and her personality.

Back in the day, the standard diamond carat for engagement rings was one carat. But over time, this diamond size has considerably gone lower perhaps due to hard economic times, urging people to be practical in so many ways including buying engagement rings.

These days, the average diamond size is less than a cart, about ¼ of a carat or ½ carat. In some more affluent states however, carat sizes can go higher than one carat; between 1.6 carats up to a whopping 2.75 carats!

Style

You will find that diamond engagement rings do not only come in the usual single diamond in the center of a gold or platinum band. There are styles that have other stones embedded on the band, surrounding the lone diamond in the center of the ring.

There are also engagement rings that have smaller diamonds on the band, again surrounding a bigger diamond in the center of the ring. The carat of these rings includes all the diamonds in the ring, from the smaller ones surrounding the band to the bigger one in the center.

Ring Size

Now the tricky part here is getting the right ring size. There are two measurements that you need to look at when choosing a ring size: the inside diameter and the inside circumference of the ring.

Understandably, you may not want to check for these specific details; all you want is to get the right ring size. Ring sizes are usually measured in inches, starting at one inch and going all the way up to sixteen inches.

Bear in mind that the ring size should also be considered for the size of the diamond that you will be getting. What you can do is to either ask one of her friends to help you pick-out the right ring size or playfully check out one of her rings, see if it fits any of your fingers and then base the size from there.

On the other hand, getting a ring size that’s a bit bigger is better than getting one that’s too small. You can always have the ring adjusted to her size after your proposal if it’s too big, with a smaller ring, this could be harder to accomplish.

Goal Post
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Goal Post

Goal post dimensions in football vary depending on whether you are playing high school football or college and professional football. NFL and NCAA goal post measurements are 10 ft. high and 18 ft. 6 in. wide; while high school football goal posts are 10 ft. high and 23 ft. 4 in. wide.