johnturley

Yes, being on the non-earth facing side of the moon, the spacecraft cannot transmit directly to the earth, it has to be via a lunar orbiting satellite. John

The BBC have repeatedly referred to where the Chinese spacecraft, which has recently landed on the far (non-earth facing) side of the moon, as being the 'Dark Side of the Moon', however where it has actually landed is in fact on the currently sunlit side of the moon, otherwise it would not have able to transmit the pictures it did, via a lunar orbiter. It never ceases to amaze me how many of the general public erroneously seem to think that the earth facing side of the moon is in permanent daylight, and that the far (non-earth facing) side of the moon is in permanent darkness, maybe the Pink Floyd album didn't help. John

It looks like the same focuser as they fit to the Esprit series. John

I use a sidereal clock (actually an app on my phone these days, although I do have an Astrotech sidereal clock), and setting circles, but you do need large accurate driven circles with a meridian pointer (which few mounts have these days), and an accurately aligned mount. You simply set the meridian pointer to the current sidereal time, and move the telescope so that the RA and Dec pointers indicate the position of Mercury. See attached photo of the RA circle and meridian pointer on my 40 year old Astro Systems fork mount. I find it fairly easy to find in daylight provided that Mercury is brighter than zero magnitude, it become increasingly difficult between zero and +1, and very difficult if fainter than +1. It is also easier to find early evening or morning than around midday, when incidentally viewing conditions are usually quite poor. It is also important to leave the telescope in focal position for your favourite eyepiece. A set of parfocal eyepieces such as the T6 Naglers (which are also parfocal with the 19 and 24mm Panoptics) also helps. This is incidentally one advantage of the T6 Naglers over the ES 82's, the latter not even being approximately parfocal. John

Had a quick observing session last night at around 22.30, first I had a look at M44 The Beehive Cluster in Cancer, which showed very nicely through the Esprit 150 using my Vixen 42mm LVW eyepiece giving 25x. I then had my first attempt to look for Comet Tsuchinsham-Atlas, I think that I could just make it out as a faint fuzzy patch through my 14in Newtonian (but was was not visible through the Esprit 150), in the predicted position. It should hopefully gradually brighten up over the next few weeks, before being lost in the summer twilight, and then re-appearing as a (hopefully) naked eye evening object in the autumn. John

You definitely will not need a flattener. John

Happy 1 April John

The latest BBC Weather Forecast is now indicating cloudy skies in Mexico on 8 April, and rain showers in Texas, ironically the best chance of clear skies now appears to be in the Great Lakes area, but all that could change. John

We were originally planning to observe the eclipse from near the Niagara Falls, followed by going to New York, and then a trans USA Amtrak Rail Trip ending up in and flying back from Sam Francisco. We decided to accept a lower chance of being able to observe the eclipse, offset by visiting New York, followed by the trans USA Rail Trip and San Francisco, however Astro Trails decided to cancel this trip due to lack of interest, so we opted for the Mexico trip instead. John

The best chance of clear skies (but not guaranteed) along the track of totality, is from the Torreon area in Northern Mexico, which is one of the observation sites that Astro Trails (UK Tour Operator) are organising, and with whom we are travelling. John

This would indicate that the Esprit 150 is significantly superior to the ED 150, I would be interested to hear from someone who has compared them. When I compared the view of Jupiter (and not under particularly good viewing conditions) through my Tak 100 DZ, with that through my Esprit 150, the 100 DZ (with a Strehl ratio measured by Rother Valley Optics of 0.987) did not even come close, the Esprit 150 was streets ahead. Note also that the 100 DZ is also technically superior to the 100 DC (which seems to be the benchmark 100mm Tak), although several observers have stated that there is no discernable difference between them. John

You could ask whether Rother Valley Optics could carry out a Zygo test on a C9.25 purchased from them, or whether they would allow you to reject the scope if it did not come up to the expected standard. I had a Zygo test carried out on my Tak 100 DZ, and the Strehl Ratio came out at 0.987, they informed me that if it didn't come up to the expected standard, then the scope is sent back to Takahashi John

Some observers used to claim that the C9.25 was superior to the C11 on planets, due to the longer (f2.5) focal ratio of the primary mirror, would be interested to hear from someone who has compared the two scopes. John

My Esprit 150 gives sharper planetary views than my 14in Newtonian on the majority of nights, although the the colour of the GRS, and the blackness of satellite shadow transits show up better through the 14in. John

I had quite a good view of Comet Pons-Brooks last night through my 14in Newtonian before it disappeared behind a neighbour's roof, and for the first time I was able to try out my Baader Swan Band Comet Filter, and it did appear to enhance the view. I would estimate that the magnitude is now around +6, in line with predictions, so it will have to brighten up quite a bit to be visible with the naked eye during the Total Eclipse of the Sun on 8 April. John