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Bringing the Universe to Your Classroom!

Sunday, July 22, 2018

4 Useful Tips for the Novice Stargazer

By Leo Eigenberg

Taking a moment to marvel at the stars in the night sky is a wonderful experience. But it can be difficult to fully appreciate what you see when everything is so far away. There are several steps that can be taken to make stargazing that much more enjoyable. Let's take a look at a few of the most useful tips:

Where to watch?

The stars are easily appreciated in the countryside or in the city. But, it will always benefit to have a high viewing platform to stop buildings or LED streetlights from having a negative impact on your view. Try to find an area that is mostly dark and clear of any light source. Streetlights can reduce your ability to see in low-light conditions which means the stars won't be so noticeable in the sky.

Stargazing - Image Credit: BBC Stargazing Live.
Stargazing - Image Credit: BBC Stargazing Live.

However, if you still want some type of light to see at night, a red flashlight will not impact your dark adaptation.

Use binoculars

Rather than invest in high-tech tools such as a telescope, you can simply start your stargazing with a decent set of binoculars. Even though they cannot give the high magnification of a telescope, they are still a great improvement on using the naked-eye. Also, it isn't necessary to pay a lot. There are plenty of budget binoculars that make it possible to see the craters on the moon.

A telescope can be used later when you have a basic understanding of the night's objects, such as the constellations or planets. Beyond searching for the most popular stars, there is also the option to look for other things such as the International Space Station.

Best time to look

The preferred time to look for stars is on the cold and crisp nights when the sky is clear. Any night with moon not present is helpful. A full moon can light the sky too much and make it difficult to see the best of the stars. The views on summer nights are likely to be less clear because of the buildup of blur and haze which will impact the view. Also, it will help if there is low or no humidity.

Use a star chart

A star chart is a useful way to learn the shape and size of the different stars in the sky. There are plenty of charts to download online. Alternatively, there are several apps that can help identify the stars, which are great for those that prefer to use modern technology.

Discover how to name a star with help from the international star registry.

Article Source:  4 Useful Tips for the Novice Stargazer
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Wednesday, July 18, 2018

2018 Mars Opposition

Like all the planets in our solar system, Earth and Mars orbit the sun. But Earth is closer to the sun and therefore races along its orbit more quickly. Earth makes two trips around the sun in about the same amount of time that Mars takes to make one trip. So sometimes the two planets are on opposite sides of the sun, very far apart, and other times, Earth catches up with its neighbor and passes relatively close to it.

During opposition, Mars and the sun are on directly opposite sides of Earth. From our perspective on our spinning world, Mars rises in the east just as the sun sets in the west. Then, after staying up in the sky the entire night, Mars sets in the west just as the sun rises in the east. Since Mars and the sun appear on opposite sides of the sky, we say that Mars is in "opposition." If Earth and Mars followed perfectly circular orbits, the opposition would be as close as the two planets could get.

Artist's concept of Mars Opposition on December 24, 2007. The distances between the sun, the planets, and the distant nebula are not to scale. Image credit: NASA.
Artist's concept of Mars Opposition on December 24, 2007. The distances between the sun, the planets, and the distant nebula are not to scale. Image credit: NASA.

Of course, nothing about motion in space is quite that simple! Our orbits are actually elliptical (oval-shaped), and we travel a little closer to the sun at one end of our orbits than at the other end.

Mars oppositions happen about every 26 months. Every 15 or 17 years, opposition occurs within a few weeks of Mars' perihelion (the point in its orbit when it is closest to the sun). This year, Mars opposition occurs on July 27, 2018.

An opposition can occur anywhere along Mars' orbit. When it happens while the red planet is closest to the sun (called "perihelic opposition"), Mars is particularly close to Earth. If Earth and Mars both had perfectly stable orbits, then each perihelic opposition would bring the two planets as close as they could be. That's almost the way it is.

NASA's Hubble Space Telescope captured this striking image of Mars during the 2016 opposition and an illustration of the relative 'tilt' in the orbits of Earth and Mars. Image credits: NASA.
NASA's Hubble Space Telescope captured this striking image of Mars during the 2016 opposition and an illustration of the relative 'tilt' in the orbits of Earth and Mars. Image credits: NASA.

But once again, nature throws in a few complications. Gravitational tugging by the other planets constantly changes the shape of our orbits a little bit. Giant Jupiter especially influences the orbit of Mars. Also, the orbits of Earth and Mars don't lie in quite the same plane. The paths the planets take around the sun are slightly tilted with respect to each other.

So, with all these added factors, some perihelic oppositions bring us closer together than others. The 2003 opposition was the closest approach in almost 60,000 years!

Mars' orbit is more elliptical than Earth's, so the difference between perihelion and aphelion is greater. Over the past centuries, Mars' orbit has been getting more and more elongated, carrying the planet even nearer to the sun at perihelion and even farther away at aphelion. So future perihelic oppositions will bring Earth and Mars even closer. But we'll still have bragging rights for a while. Our 2003 record will stand until August 28, 2287!

Article Source: Mars in Our Night Sky - Mars Opposition
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Wednesday, July 11, 2018

Buying A Good Telescope - One Very Good Option

Thinking about buying a *good* telescope someday?

I'm glad you are because I've got some news for you about telescopes, generally.

Most people who are considering having a telescope in their lives, look for them in a department store. Now, department stores are great! At least, I love them. But they are limited in scope (oh, what a perfect spot for that pun!), naturally, where specialty items are concerned - and telescopes are a big one.

Some of the names of the telescopes found, in some department stores, will be familiar to you, such as, "Celestron®", or Meade®, or Tasco®. But, though these are three of the *big* names in telescopes, the models you'll find are built for the masses - for those who aren't likely to be very discerning, in an area you really *need* to be very discerning with. The associated advertising agencies use a factor in telescopes regarding magnification as their main selling point which is, inherently, not exactly 'wrong' - but not relevant, either.

Ken from Orion Telescopes and Binoculars Demonstrates the XT-8 SkyQuest Plus Dobsonian Telescope Image by Orion Telescopes and Binoculars.
Ken from Orion Telescopes and Binoculars Demonstrates the XT-8 SkyQuest Plus Dobsonian Telescope
Image by Orion Telescopes and Binoculars.

You'll see such wording on their packaging, as: "300x",  "300-power", "300 times", etc., meaning, that the instrument will/can magnify an object to 300 times its normal diameter, or, it's apparent size as seen with the unaided eye. DON'T, DON'T, DON'T DO IT! There are two areas that I know of, personally, where the quality of an instrument can make or break a beginner, particularly, and especially children: guitars, and telescopes...

*Any* telescope, can achieve *any* of the "powers", or magnifications, available to it; all you have to do, is, insert a 'high-power' eyepiece, known as an 'ocular', into the focuser's draw-tube; most telescopes are supplied with a small assortment of eyepieces of various focal-lengths, which will change the 'power' (in that context) of the instrument. That action can make, or break a telescope. The real 'power' of a telescope is in the size of its aperture; i.e., in the diameter of its primary mirror or lens, depending on the type of telescope it is. Having a better quality instrument will be the difference between one that is actually used, and one that ends up in the attic or basement - collecting dust - for the next 25 years. I've seen it myself, and it happened to me - but only once - as a kid. I was fortunate enough to have the presence of mind to research telescopes, and decide on one that I could really use.

If you're considering a telescope for a child and are concerned about putting up an amount of money, for something that may just end up getting abandoned, then you need to avoid the department stores, absolutely. You'll save money and get a far better instrument from a well-known, reputable manufacturer of telescopes for the amateur astronomer.

Orion Telescopes and Binoculars is such a place, and, in my opinion, is who you want - take my word for that. Every astronomer, amateur or professional, would most likely agree with this if they're at all familiar with this company. There are a few other manufacturers of good telescopes out there (but not many), but Orion stands out, by their reputation for integrity, alone. They are willing to go the extra mile to satisfy a customer. Their company was started by amateur astronomers, for amateur astronomers. I've been dealing with these telescope 'specialists', since 1982.

The two scopes shown below, are, probably, THE best buys in telescopes, period. They are, *real* optical instruments, rather than the *toys* found in the department stores that, I've referred to. It IS possible to find a good telescope at a department store - but it isn't likely, or worth the risk.

Jupiter and one of its moons imaged through an Orion XT-6 SkyQuest  Imaged by Orion Telescopes and Binoculars.
Jupiter and one of its moons imaged through an Orion XT-6 SkyQuest
Imaged by Orion Telescopes and Binoculars.

The scopes shown in this article, are two configurations of the Orion XT-6, and Orion XT-8 'SkyQuest' series of Dobsonian-mounted, Newtonian, reflector telescopes. The numbers refer to the diameter of the instruments primary apertures, respectively. As telescopes go, they would be considered *medium-sized* telescopes. Moreover, scopes in this size range are perfectly suited to adults, as well, of course. They are in every respect - "two steps" up from the typical, department store telescope. With these instruments, you will not only be able to observe the moon and planets, you will see many of the gaseous, hydrogen nebulosities of the Milky Way, known as, "nebulae", as well as many of the other galaxies, beyond our Milky Way galaxy! And - you're not going to beat their price. Orion also makes smaller, and less expensive instruments, all the way down to tabletop telescopes, and - they make much larger instruments, as well - up to 16"-inch, entirely computerized, observatory-sized beauties!


Jupiter imaged through an Orion XT-8 SkyQuest Plus - Image by Orion Telescopes and Binoculars.
Jupiter imaged through an Orion XT-8 SkyQuest Plus - Image by Orion Telescopes and Binoculars.


You can download one of their catalogs, at www.telescope.com

So - good luck, and good judgment, and, as we say:

"Clear Skies!", to you!
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