Sky Events

July 27th: MARS Opposition and Lunar Eclipse

Mars at 7820mm (2018Jun04) on, ©Frederick Steiling.  Tele Vue 2x Powermate™ on C14 with ZWO ASI174MM camera using IRRGB filters. Image from June 4, 2018 before dust storm overtook the whole planet.

Mars will exceed 24-arc-sec in diameter between July 23rd and August 9th, 2018. This is 97 percent of the maximum of 25.13-arc-sec diameter attained during the last of the ‘favorable’ apparitions, which occurred in 2003.Association of Lunar and Planetary Observers

Mars is an “outer planet”: its orbit is outside that of Earth. Opposition: Earth and outer planet line up on on same side with Sun (bottom of diagram). Conjunction: Earth and outer planet line up on opposite sides of sun (top of diagram). Courtesy NASA/JPL-Caltech.
The night we’ve been planning for all-year is only a few days away: on July 27, 2018, Mars will be in opposition (see diagram left) at a distance of 35.9-million miles / 57.8-million km — not far off from the very close 2003 opposition distance of 34.6-million miles / 55.8-million kilometers . Due to orbital eccentricity, Mars and Earth continue to draw ever-closer after the opposition, with the distance shrinking by another 111,000-miles / 179,000-km when they are actually nearest on July 31, 2018. So this is not a one-night event. In fact, the Association of Lunar and Planetary Observers notes that “Mars will exceed 24-arc-sec in diameter between July 23rd and August 9th, 2018. This is 97 percent of the maximum of 25.13-arc-sec diameter attained during the last of the ‘favorable’ apparitions, which occurred in 2003.”
Nagler 3-6 Planetary Zoom.

For viewing the red planet you’ll have to “up” the power to the limit of atmospheric conditions. That’s where the Nagler 3-6mm Planetary Zoom comes in handy: an eyepiece with full field sharpness for any speed telescope, high contrast and transmission for natural color rendition, low scatter, comfortable eye-relief, with adjustable magnification to match the seeing conditions that can change a lot over the course of an observing session. It’ll give you up to 120x in our Tele Vue-60 and 220x in our Tele Vue-NP127is. It will exceed over 300x in most Dobs, SCTs, and Maks.

Tele Vue’s 2.5x Powermate™.

If you have a favorite eyepiece that lacks the power for planetary usage or plan on imaging the planets, consider our Powermates™: they are the solution for any scope to achieve the long focal-length required to see details on planetary bodies. Powermates™ increase the effective focal length of your scope without introducing any new aberrations into the system. They are available in 1¼” barrels (2.5x & 5x) and 2″ barrels (2x & 4x) and can  be stacked (e.g.: a 2x and 4x Powermate™ will increase focal length by 8x) . 

PTR-1250 Powermate T-Ring Adapter for 2.5x & 5x Powermates.

The benefits of Powermates™ extend to imaging. This requires an optional Powermate™ T-Ring Adapter that allows a Powermate™ to connect with any T-Ring equipped camera.  A Powermate™ with the adapter can by used singly or stacked with another Powermate™, to achieve the long effective focal-length required for planetary imaging.

2″ BIG Barlow

Properly designed Barlows do wonderful things: They amplify power, slow the telescope’s f/# (improving eyepiece sharpness), and give designers the opportunity to compensate for eyepiece aberrations.

Tele Vue Barlows are the entry-level alternative to Powermates™ . We use high index glasses for optimum aberration correction and ultra-high efficiency multi-coatings for exceptional contrast with virtually no light loss. They are even tested for performance with f/4 scopes — the same full-field testing as all our eyepieces. 

Tele Vue Barlows are available in 1¼” barrels (2x & 2x) and 2″ barrels (2x BIG Barlow).

If you post an observation or photograph on social media, made with Tele Vue gear, put #televue in your post and we’ll like it.

Total Lunar Eclipse: October 27-28, 2004 taken with Tele Vue-NP101 telescope. Credit and copyright Pete Lardizabal.

Coincidentally, July 27th will also feature the second lunar eclipse of the year. It’s not just any lunar eclipse: it is the longest total eclipse this century with totality spanning 1-hr 43-min (just missing the maximum duration by a few minutes). The entire event will be visible in East, Southern, and Central Africa, the Middle East, India, Turkey, and most of Kazakstan. Missing out on the event will be observers in North America, Greenland, Central America, Siberia, and the Arctic. The rest of the world will see part of the event.   
“Five Millennium Catalog of Lunar Eclipses: -1999 to +3000” (NASA/TP-2009-214173). Darkest areas of the globe do not see the eclipse

Additionally, the full moon that day will be a micromoon: an usually small full moon. That’s because it’ll be furthest from earth (apogee) less than 15-hours before becoming full. See our 2018: Solar and Lunar Phenomena Overview blog post for information on lunar eclipses, blue moons, and micro/supermoons. 


To image the lunar eclipse, the Tele Vue FoneMate smartphone adapter is a must. It solidly mates your smartphone to many of our Tele Vue eyepieces to allow still image and video capture using the camera/video app on your phone. You can download a time-laps imaging app to capture the progress of the lunar eclipse over time.

Smartphones as big as the Galaxy Note 4 (shown) can be fitted to the FoneMate™ for imaging through select Tele Vue eyepieces.
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