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Posts Tagged ‘Messier Catalog’

05/16/2017 – Ephemeris – The Virgo Cluster of Galaxies

May 16, 2017 Comments off

Ephemeris for Tuesday, May 16th.  Today the Sun will be up for 14 hours and 51 minutes, setting at 9:05, and it will rise tomorrow at 6:12.  The Moon, 2 days before last quarter, will rise at 1:43 tomorrow morning.

Yesterday I talked about the constellation of Virgo the virgin.  When we are looking at the constellation of Virgo, we are looking out the thin side of our galaxy, the Milky Way.  The Milky Way galaxy is a flat disk.  When we look into the disk we see the milky band we call the Milky Way. That band, what we can see of if is now low in the north, So the stars are much more sparse with the exception of those relatively close to us, like those of the big Dipper.  Beyond the stars of Virgo is a huge cluster of over a thousand galaxies.   Charles Messier, a comet hunter of the late 18th century, ran into quite a few fuzzy spots between Virgo and Leo to the upper right.  Because they didn’t move in relation to the stars, they couldn’t be comets, so he added them to his list of nuisance objects, which we now enjoy looking at.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Virgo cluster

Some of the brighter members of the Virgo Cluster (of galaxies) as tiny red ovals. The galaxies marked with an ‘M’ number are part of Charles Messier’s catalog. It took a telescope of 8 inch diameter for me to spot them. Someone with better vision, like Messier himself can spot them with a smaller telescope. Created using Cartes du Ciel (Sky Charts).  Click on image to enlarge.

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Ephemeris Extra – Autumn telescopic wonders

November 6, 2016 Comments off

This is an updated article I wrote from the October 1998 issue of the Grand Traverse Astronomical Society’ newsletter the Stellar Sentinel

18 years ago Judy, my late wife, and I bought a telescope from Enerdyne. Officially it was Judy’s telescope and is a Celestron 11 inch (280 mm) Star Hopper Dobsonian. After over 20 years of relying on the telescopes at the Lanphier and Rogers observatories, we felt the need again for a personal backyard telescope again. This was also brought home by the appearance of the comets Hyakutake and Hale-Bopp in the 1996 and 1997.

Though large in diameter, the telescope has a focal length of 49.5 inches (1260 mm), much closer to the telescopes I’ve made and used in the past, and a third to a half the diameter of the C14s at the observatories above. So the scope gives bright low power views of galaxies and nebulae. The diameter allows the resolution of some globular clusters. I was also quite pleasantly surprised at the scope’s ability to see detail on Jupiter and Saturn. Jupiter’s Great Red (currently a pale pink) Spot and on Saturn: a cloud band, ring shadows and Cassini’s Division.

Soon after obtaining the telescope I surveyed the dim wonders of the autumn sky beyond the solar system. Here are the results:

Galaxies

  • M31, M32 and M110 Better known as the Great Andromeda Galaxy and its companion galaxies, the view is made to order for the smaller telescope. M31’s glowing nucleus spans the eyepiece field. The galaxy is larger than out own and lies at a distance 2.5 million light years. The brightness falls off sharply along the north side of it’s elliptical minor axis. The nearly spherical M32 is seen nearby, while the faint elliptical galaxy M110 is barely visible on the other side of M31. I used to know M110 only as NGC205.  It was added to Messier’s list in 1967, 11 years after I first observed the galaxy.
    A note about The M designations.  They are from a catalog started by French comet hunter Charles Messier (1730-1817) who made a list of fuzzy objects in the sky that could be confused as being comets because they didn’t move against the stars.   He officially discovered or co-discovered a dozen comets.  As can be seen by the inclusion Of M110, it has been extended by other astronomers.
  • M33 The Triangulum galaxy is seen nearby off the point Triangulum is about as close as M31, but smaller than M31 with a small nucleus and large faint disk. It has a very low surface brightness and requires a dark sky.
  • M74 Is located in Pisces near Aries. It is a face-on galaxy like M33 but a lot smaller and fainter. I saw no central condensation.
  • M77 is a different story, a galaxy with a bright nucleus. M77 is located is Cetus located just below the head of the monster or tail of the whale, however you see him.

Globular star clusters

  • M15 is a globular cluster found by extending the nose of Pegasus. The 11 inch telescope could resolve the cluster’s outer stars. It was a smaller, dimmer version of M13, the grand globular in Hercules.
  • M2 is a more distant globular located due south of M15 and at an equal declination as (α)Alpha Aquarii or Sadal Melik. It earns its inclusion as Messier’s object number 2, for it looks for all the world like a tailless comet. On a second look at it the 11 inch could resolve a few stars.
  • M30 seems the same size as M2 and located farther south just right of the star (ζ)Zeta Capricorni. However the 11 inch can resolve a handful of its brighter stars.

As we move outward from the galactic center in Sagittarius the globular clusters thin out dramatically. The next Messier globular is located in Lepus the hare below Orion a winter constellation.

Open or galactic clusters

  • M34 is a large but sparse open or galactic star cluster located just west of the star Algol in Perseus.
  • M103 is a faint triangular-shaped cluster located just east of the star (δ)Delta Casseopeiae. The triangular arrangement of its stars reminds me of a smaller version of the Beehive Cluster (M44) in Cancer.
  • M52 is a faint but populous cluster located between Cassiopeia and Cepheus.
  • The Double Cluster is a great view in a low power eyepiece. The two clusters do not have Messier designations. But they do have NGC numbers: 869 and 884. NGC is the “New General Catalog” and is not so new. It’s over 100 years old.
  • M45 or the Pleiades is best seen in a pair of binoculars. Also known as the Seven Sisters, the Pleiades is close as star clusters go at 400 light years.
  • Melotte 25 or Collinder 50:  The Hyades, the face of Taurus the Bull, is the closest star cluster of all at about 153 light years. Sparse and big, it is almost too large to view in a pair of binoculars. The Hyades is the key to finding distances to the ends of the universe. It is close enough to get good parallax data for triangulation. Its many stars of known brightness and distance can be matched to other star clusters beyond the reach of the parallax method to ascertain their distances.

M76 is the only planetary nebula in our group. Called the Little Dumbbell Nebula or the Barbell Nebula, it has a shape of one of those Milk Bone dog biscuits.

Autumn telescopic wonders


A star chart covering the autumn constellations and the objects described in this article. In Andromeda (And) the overprinted captions are for M31 and M32. The Double Cluster is not shown, not being a Messier object. It’s approximately half way between the northernmost star of Perseus (Per) and M103 in Cassiopeia (Cas). The article doesn’t cover the Messier objects M35, 26, 37 ,38, 42/3 and 78. Which I may do for winter. The star chart was created using the author’s program LookingUp.

09/04/2015 – Ephemeris – Astronomy tonight, occultation after midnight

September 4, 2015 Comments off

Ephemeris for Friday, September 4th.  The Sun will rise at 7:08.  It’ll be up for 13 hours and 6 minutes, setting at 8:14.   The Moon, 1 day before last quarter, will rise at 12:10 tomorrow morning.

This evening at 8 p.m. the Grand Traverse Astronomical Society will hold its monthly meeting at Northwestern Michigan College’s Rogers Observatory featuring a talk by observatory director Jerry Dobek about the deep sky wonders visible in small telescopes from Charles Messier’s catalog.   At 9 p.m. there will be a star party featuring Saturn and some of these wonders in the summer Milky Way.  Not part of the star party, the Moon will rise about 12:10 a.m. covering or occulting the bright star Aldebaran.  For northwest lower Michigan. Aldebaran should pop into view at the Moon’s dark upper edge at around 12:40 a.m.  The exact time is dependent on your actual location, so go out 5 minutes before.  [http://www.lunar-occultations.com/iota/bstar/0905zc692.htm]

Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.

Addendum

Here’s a website where the occultation of Aldebaran is covered, including a map of the area where it may be viewed.  This includes Europe.

05/08/2015 – Ephemeris – May’s missing Milky Way

May 8, 2015 Comments off

Ephemeris for Friday, May 8th.  Today the Sun will be up for 14 hours and 32 minutes, setting at 8:55.   The Moon, 3 days before last quarter, will rise at 1:08 tomorrow morning.  Tomorrow the Sun will rise at 6:22.

In May we look up to the sky and notice that the Milky Way is missing.  Will not really it’s as if the sky has pattern baldness with the Milky Way as a fringe on the horizon around the north half of the sky.  Overhead, where none should be is a galactic star cluster, a star cluster that should normally be in the Milky band.  That cluster is the constellation of Coma Berenices.  Its is a sparse star cluster of about 50 stars only 288 light years away.  If we were a thousand light years from it, it would appear in the Milky band.  One notes too that the stars of spring are also fewer, not the riot of stars we see in the winter or late summer.  The Milky Way galaxy is a thin disk, and in spring we are looking out the thin side.

Times are for the Traverse City/Interlochen area of Michigan.  They may be different for your location.

Addendum

May 2015 Star Chart

Star Chart for May 2015. Note the Milky way in the north.  The Coma Berenices cluster is located between the labels CnV and Com.  Created using my LookingUp program.

Messier objects  in the spring sky.

Messier objects, mostly galaxies (ovals) in the spring sky. Created using my LookingUp program.

Most of the galaxies in the above chart belong to the Virgo Cluster a cluster of several thousand galaxies about 53 million light years away.  Charles Messier was a comet hunter active in the period around the time of the American Revolution at the Paris Observatory.  He made a catalog of fuzzy objects he ran into that didn’t move and thus were not comets.  The Messier catalog, which ran to 110 galaxies, star clusters and nebulae, some added posthumously, became a must-see list of some of the best sights for the telescope.