viewing comfort, and helps bring out the subtle features if the lunar surface.
B. The Sun
You can change your nighttime telescope into a daytime Sun viewer by installing an optional full-aperture solar filter over the front opening of a SkyView Pro 150mm EQ. The primary attraction is sunspots, which change shape, appearance, and location daily. Sunspots are directly related to magnetic activ‑ ity in the Sun. Many observers like to make drawings of sun‑ spots to monitor how the Sun is changing from day to day.
Important Note: Do not look at the Sun with any optical instrument without a professionally made solar filter, or permanent eye damage could result. Also, be sure to cover the finder scope, or better yet, remove it altogether.
C. The Planets
The planets don’t stay put like the stars, so to find them you should refer to Sky Calendar at our website OrionTelescopes. com, or to charts published monthly in Astronomy, Sky & Telescope, or other astronomy magazines. Venus, Mars, Jupiter, and Saturn are the brightest objects in the sky after the Sun and the Moon.Your SkyView Pro 150mm EQ is capa‑ ble of showing you these planets in some detail. Other planets may be visible but will likely appear starlike. Because plan‑ ets are quite small in apparent size, optional higher power eyepieces are recommended and often needed for detailed observations. Not all the planets are generally visible at any one time.
JUPITER The largest planet, Jupiter, is a great subject for observation. You can see the disk of the giant planet and watch the ever-changing positions of its four largest moons— Io, Callisto, Europa, and Ganymede. Higher power eyepieces should bring out the cloud bands on the planet’s disk.
SATURN The ringed planet is a breathtaking sight when it is well positioned. The tilt angle of the rings varies over a peri‑ od of many years; sometimes they are seen edge-on, while at other times they are broadside and look like giant “ears” on each side of Saturn’s disk. A steady atmosphere (good seeing) is necessary for a good view. You will probably see a bright “star” close by, which is Saturn’s brightest moon, Titan.
VENUS At its brightest, Venus is the most luminous object in the sky, excluding the Sun and the Moon. It is so bright that sometimes it is visible to the naked eye during full daylight! Ironically, Venus appears as a thin crescent, not a full disk, when at its peak brightness. Because it is so close to the Sun, it never wanders too far from the morning or evening horizon. No surface markings can be seen on Venus, which is always shrouded in dense clouds.
MARS The Red Planet makes its closest approach to Earth every two years. During close approaches you’ll see a red disk, and may be able to see the polar ice cap. To see surface detail on Mars, you will need a high power eyepiece and very steady air!
D. Deep-Sky Objects
Stars will appear like twinkling points of light. Even powerful telescopes cannot magnify stars to appear as more than a
point of light! You can, however, enjoy the different colors of the stars and locate many pretty double and multiple stars. The famous “Double-Double” in the constellation Lyra and the gor‑ geous two-color double star Albireo in Cygnus are favorites. Defocusing a star slightly can help bring out its color.
Under dark skies, you can observe a wealth of fascinating deep-sky objects, including gaseous nebulas, open and glob‑ ular star clusters, and a variety of different types of galaxies. Most deep-sky objects are very faint, so it is important that you find an observing site well away from light pollution. Take plenty of time to let your eyes adjust to the darkness. Do not expect these subjects to appear like the photographs you see in books and magazines; most will look like dim gray smudg‑ es. But as you become more experienced and your observing skills get sharper, you will be able to ferret out more and more subtle details and structure.
How to Find Deep-sky Objects: Starhopping
Starhopping, as it is called by astronomers, is perhaps the simplest way to hunt down objects to view in the night sky. It entails first pointing the telescope at a star close to the object you wish to observe, and then progressing to other stars closer and closer to the object until it is in the field of view of the eyepiece. It is a very intuitive technique that has been employed for hundreds of years by professional and amateur astronomers alike. Keep in mind, as with any new task, that starhopping may seem challenging at first, but will become easier over time and with practice.
To starhop, only a minimal amount of additional equipment is necessary. A star chart or atlas that shows stars to at least magnitude 5 is required. Select one that shows the positions of many deep-sky objects, so you will have a lot of options to choose from. If you do not know the positions of the constel‑ lations in the night sky, you will need to get a planisphere to identify them.
Start by choosing bright objects to view. The brightness of an object is measured by its visual magnitude; the brighter an object, the lower its magnitude. Choose an object with a visual magnitude of 9 or lower. Many beginners start with the Messier objects, which represent some of the best and bright‑ est deep-sky objects, first catalogued about 200 years ago by the French astronomer Charles Messier.
Determine in which constellation the object lies. Now, find the constellation in the sky. If you do not recognize the constella‑ tions on sight, consult a planisphere. The planisphere gives an all-sky view and shows which constellations are visible on a given night at a given time.
Now, look at your star chart and find the brightest star in the constellation that is near the object you are trying to find. Using the finder scope, point the telescope at this star and center it on the crosshairs. Next, look again at the star chart and find another suitably bright star near the bright star cur‑ rently centered in the finder. Keep in mind that the field of view of the finder scope is approximately 5°, so you should choose another star that is no more that 5° from the first star, if possible. Move the telescope slightly, until the telescope is centered on the new star.
