Moon passes through Beehive Cluster

Moon Occults Stars in Beehive Cluster May 10, 2019
by John Hlynialuk
On Friday night, May 10, from 10 pm local time or so until after midnight, several stars in the southern part of the Beehive Cluster will be occulted by the 6.3 day-old crescent Moon. Some of the stars are double, one is triple and one is quadruple, and though these will be difficult to observe in the vicinity of the bright Moon, they may be still “observable” -read on.


Stars of 6th and possibly 7th magnitude will be detectable, but don’t count on seeing 12th magnitude in the bright moonlight. In any case, there may be a possibility of “detecting” the doubles or multiples as step-wise changes in the light level. First one, then the other of the close pair is occulted by the optically very shape moon’s edge -a sequence that may take only a fraction of a second, but if you look for it, it may be detectable. Event no. 5 and 9 are good candidates for these. If you see a drop in the light from the star that looks like it faded first, then went out entirely, that may be each star blinking out in succession.

In general, occultations of stars by the Moon are neat to watch and occur fairly often. In 2019, the RASC Observer’s Handbook list 32 of these (for Toronto) and though there are no 1st magnitude stars involved, there is Tejat, μ-Geminorum, a 2.9 magnitude star occulted twice late in the year. Also, for this area will be a daytime occupation of Venus by the very thin crescent Moon only 4 degrees from the Sun on July 31.

Occultations of stars by the dark limb of the Moon are almost instantaneous and especially neat if there are several total occultations in series like we get May 10 or during totality of lunar eclipse. One gets a real sense of the Moon’s motion through the heavens from events like these.
Click on the diagram and/or table below to download a copy

M44 Moon pass May 10_edited-1

Diagram above from Sky Safari (with additional graphics added) illustrates the path of the 38% sunlit Moon passing through M44 from 10:10 pm EDT to just after midnight May 11. A pdf version of the star chart is available on the BAS website. Chart above does not show BS Cancri (BS Cnc) No.1 below, the first star to be occulted, and it will be faint, almost 9th magnitude.


Screen Shot 2019-04-13 at 6.51.02 PM

Table above gives times of events determined manually from Sky Safari 5 Pro for Owen Sound, ON. Times will not vary too much from these values if you are within 20 or 30 km of Owen Sound and are conservative (early) by about a minute. But if you are farther west times can be several, meaning many, minutes early and the opposite, later, to the east. Check your own software for your own geographic location. Differences of 15 minutes or more will occur across a province like Ontario.

Mars near Pleiades for a week!

Mars Near Pleiades
by John Hlynialuk

The end of March will go out with a nice view in the west just after sunset. Especially if you want to get a sense of how quickly planets move across the sky. The players involved are Mars and M45, the Pleiades Cluster. In the last week of March and the first week of April, Mars will be slipping past the Seven Sisters in the western sky. The closest approach (appulse) occurs on March 30 & 31 when the separation is about 3 degrees 9 minutes of arc. The spacing is under 5 degrees for a lot longer than that, from March 25 to April 6, so anytime during that interval will provide a nice photo opportunity.

Mars March 28 to Apr 3

The sky will be dark for the evening hours when Mars is above the horizon since the Moon is in last quarter (March 28) or new phase (April 6) and does not rise until the wee morning hours. The waxing 2 or 3 day old crescent does finally appear on the scene by Apr 7 or so -it is a nice addition to the group April 9.

The event will be visible nightly from sunset to about midnight when Mars finally sets below the western horizon so there is lots of time from sunset until midnight to catch a view of the planet and M45. Mars continues climbing eastwards in the SW sky for several more months crossing Taurus into Gemini and then finally getting lost in the Sun’s glare in Cancer in late June.

Diagram above shows the path of Mars from March 28 to Apr 3, 2019.

Mars and Neptune REAL close Dec 7

by Brett Tatton

I hope we get to observe Neptune and Mars next week when they are as close to each other as one half the Moon's diameter!

Mars will be quite obvious in the south above bright Fomalhaut -Alpha Piscis Austrini (the Alpha star of the Southern Fish).


I made these finder charts with Sky Safari to help show the area of sky and then to provide enough detail to help identify Neptune.

IMG_1745

Finding Neptune using Mars alone may not be the way to go. The relative position of Neptune to the Red Planet is changing as Mars streaks across the sky! Alternatively I suggest using 81 and 82 Aquarii as pointers. (See last chart below) Eighth magnitude Neptune is almost in a line with these two magnitude 6 stars.

IMG_1747

On the detailed chart (below) I have identified the star HD217572 for you to use as a brightness comparison to Neptune. Both are at about magnitude 8 (give or take a decimal).

IMG_1749

I hope the skies co-operate and I hope these notes and the charts will help you to zeroing in on Neptune!
Brett

ANOTHER COMET for Christmas???

Comet Alert! A new comet has been discovered!

Comet C/2018 V1 (Macholtz-Fujikawa-Iwamoto -henceforth Comet M-F-I) was just discovered (Nov 7) and it gives us another opportunity to spot a comet this year (along with Wirtanen which is also brightening on schedule -last estimate magnitude 7).
Below is the Sky and Telescope finder chart. C/2018 V1 passed the star Porrima in Virgo Wed am Nov 12 and it is tracking eastwards (left) over the next few weeks as it gradually approaches the Sun. It transitions into the evening sky in early December.

Comet C/2018V1 is now 8th magnitude or brighter!
Look East at the start of morning twilight towards Venus and Spica in Virgo. The comet is moving generally eastwards towards the sunrise Virgo and gets closest to the planet on Nov 18 (only 10° from Venus at magnitude -4). The moon is nowhere in the sky at this time of morning and it is worth getting up before dawn to have a look. The comet should brighten perhaps to magnitude 5 or so as it approaches the Sun but it will also become lost in the glare by month end. See the charts at the bottom of this weblog. Rounding the Sun in early December, it switches over into the evening sky and will perhaps be its brightest then. Comet M-F-I is not predicted to get as bright as Wirtanen but these objects are of course, unpredictable. Read all about the discovery here: https://www.skyandtelescope.com/astronomy-news/observing-news/machholz-12th-comet/
An image taken Nov 11 is provided at the S&T link above and I include it below. Don’t expect it to look like this visually, this is a long exposure image. There may be a hint of green colour, however.

pastedGraphic
The new comet, now formally named C/2018 V1 (Machholz-Fujikawa-Iwamoto) glows green and sports a faint tail pointing west-northwest in this image taken on Nov. 11.
Michael Jäger

Here is one website (IAU Minor Planet Centre) which will give you the elements of the orbit that you can enter into a program like Starry Night to create the path for yourself: https://www.minorplanetcenter.net/iau/Ephemerides/SoftwareEls.html

Star charts for morning viewing from Nov 22 to Nov 28 and evening viewing from Dec 2 to 10 are provided below. Click to download copies.


C-MFI-Nov-22-28

C-MFI-Dec-2-10

Christmas Comet? Maybe


A Comet for Christmas?
by John Hlynialuk

While there has been no lack of planetary activity to enjoy in the night sky (Venus, Jupiter and Mars!), one celestial spectacle has been missing for a long time. We have not had a bright comet for a dozen years or so and any that have shown up have required telescopes or binoculars to see. The most recent one was Comet 26P/Giacobini-Zinner and it was captured nicely on camera by Frank W. See the
HOME page.

We are long overdue for a really bright comet and although I would like to report otherwise, the comet predicted for Christmas will be a good comet, but not likely a spectacular one. However, as one famous comet hunter, David H. Levy commented, “Comets are like cats: they have tails and do precisely what they want.”

Of all celestial objects, comets are the most elusive and most unpredictable. Astronomers know many of their orbits with high precision, but their behaviour when these chunks of frozen ice and gas get near the Sun is much less certain. Many do not brighten on schedule, some break up or get destroyed by a close pass to the Sun and others burst forth in spectacular fashion. The most famous example of a much-ballyhooed comet that flopped was Comet Kohoutek in 1973. I tried more than once to catch a glimpse of Kohoutek and failed, and my better half notes (with glee) that she spotted it casually during a snowmobile ride on a frozen lake in the Peterborough area. (That was in our pre-courting days, so it does not really count.)

As in the case of Comet Kohoutek, comets can be a complete fizzle, or they can totally defy predictions and be easily seen even from our brightly-lit cities. The last such comet was Comet Hale-Bopp in 1997 with a spectacular show for over a year remaining visible to the naked eye for 18 months. But who remembers Comet Hyakatake? This one appeared a year before Hale-Bopp, had a larger tail, and came closer to Earth (a close shave of only 15 million km) than the 200 million km wide pass of Hale-Bopp.
23HyakApr:96Hale-Bopp-comet-1997_edited-1
Image left: Comet Hyakatake imaged from April 1996 Image right: Comet Hale-Bopp at its best in March 1997 Both images by John H.

Unfortunately Hyakatake only appeared for 3 months in 1996 during typically cloudy spring weather, and you had to be dedicated to spot it. I had learned a lesson with Kohoutek, and thankfully, the weather cooperated, so I did observe and photograph it on several occasions.

This Christmas, Comet 46/P Wirtanen is expected to appear in our skies, and away from city lights (and moonlight), it may be an interesting sight. Due to be brightest during the later part of 2018 and early January 2019, predictions (for what those are worth) are that it may get to be visible to the naked eye, -but don’t expect another Hale-Bopp.

Comet 46/P Wirtanen was preceded by another, a summer comet, Comet Giacobini-Zinner, and if predictions are borne out, Comet 46/P will be better than Comet G-Z and should peak late in the year. The best times to view will be during Moon-free periods in the first two weeks of December and again in the first part of January 2019. Full Moon occurs Dec 22 and Wirtanen will not likely be seen over the bright moonlight. But if you can dodge the moon by waiting for it to set, Wirtanen will be above the horizon all night long from mid-December into the new year. For a chart showing the path of 46/P from Dec 1 to Christmas Day see below:
Wirtanen-Dec-1-to-25

Additional information about Comet 46P/ can be found on the VIS.COMETS page. Click on the map to download a copy. Good luck with your comet viewing!