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Bristol Astronomical Society Information Leaflet
March 2016
The Beehive Cluster (M44)
NGC 2775
2m Telescope at Haleakala
60 s Exposure, Jan 2013
King's School, Canterbury, Kent, UK
2m Telescope at Haleakala
360 s Exposure, Feb. 2012
UoG11 - Helen Usher
Sirius (α Canis Majoris)
NGC 2207 & IC 2163
2m Telescope at Siding Spring
15 s Exposure, Jan 2014
Kings Of Wessex Academy
2m Telescope at Haleakala
60 s Exposure, Dec. 2014
USW
Images from the
Las Cumbres Observatory Global Telescope
(LCOGT) Network
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Observing Calendar March 2016
Observing Calendar March 2016
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The Sun
The Moon
Sun’s Position at Midday 15th March 2016
March 16th and 29th: The Alpine Valley
Solar Events for 2016
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These are two good nights to observe the Alpine Valley on the Moon if you
have a small telescope. Close to the limb is the Appenine mountain chain
that marks the edge of Mare Imbrium. Towards the upper end you should
see the cleft across them called the Alpine valley. It is about 7 miles wide
and 79 miles long. As shown in the image over the page, a thin rill runs
along its length which is quite a challenge to observe. The dark crater Plato
will also be visible nearby. You may also see the shadow cast by the mountain Mons Piton lying not far away in Mare Imbrium.
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The Moon
The Planets
March 1st at 00:00
March 15th at 00:00
March 31st at 00:00
The Crater Plato and the Alpine Valley
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‘Sky This Month’ : www.jb.man.ac.uk
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www.heavens-above.com
The Planets
The Planets
Mercury
Jupiter
Mercury passes behind the Sun (superior conjunction) on the 23rd March,
so this is not a good month to observe it..
March is a superb month to observe Jupiter. It now lies in Leo and so is still
reasonably high in the ecliptic and hence, when due south, at an elevation
of ~48 degrees. Sadly, this peak elevation is reducing at each apparition. The features seen in the Jovian atmosphere have been changing
quite significantly over the last few years - for a while the South Equatorial
Belt vanished completely but has now returned to its normal wide state.
Venus
Venus rises in the east-southeast about an hour before sunrise as March
begins but, only about 25 minutes before sunrise by month's end. Its magnitude stays steady at -3.8 as it slips into the sun' glare. A low horizon will be
needed to spot it before it becomes hidden behind the Sun in April..
Mars
Mars , moving eastwards relative to the stars, starts the month in Libra and
moves into Scorpius on the 14th of the month when it will lie very close to
the star Acrab which forms the uppermost star of the fan of stars up to the
right of Antares. It is best seen due south before dawn but, sadly like Saturn, will then be only ~19 degrees above the horizon.
It increases in magnitude from +0.3 to -0.1 during the month as the angular
size of its disk increases from 8.7 up to 11.7 arc seconds. Given good
'seeing' some features on the disk should now be visible such as the North
Polar Cap and Syrtis Major. At opposition at the end of May the disk will be
over 15 arc seconds across..
March 5th, before dawn: Saturn, Mars and Antares
Before dawn on March 5th, Saturn and Mars will be seen above the star
Antares, in Scorpius.
March 16th before dawn: Mars very close to Beta Scorpii
Before dawn on the 16th March, Mars will be seen in very close proximity
to the star Beta Scorpii - the topmost star in the scorpion's tail fan.
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Jupiter reaches opposition on the 8th of March - it is visible through the
whole of the night. It starts March shining at at magnitude -2.5, dropping
slightly to -2.4 as the month progresses. Jupiter is still moving slowly westwards across the lower part of Leo towards Regulus. The size of Jupiter's
disk falls slightly from 44.4 to 43.7 arc seconds as March progresses. With
a small telescope one should be easily able to see the equatorial bands in
the atmosphere, sometimes the Great Red Spot and up to four of the Gallilean moons as they weave their way around it.
Great Red Spot on Jupiter
This list gives some of the best evening times during March to observe the
Great Red Spot which should then lie on the central meridian of the planet..
1st 23:10 4th 20:39
6th 22:17 11th 21:24 13th 23:02 16th 20:31
18th 22:09 20th 23:47 23rd 21:17
25th 22:55 28th 20:24 30th 22:02
Mar. 16th ~10 pm: Ganymede & Io transit
Around 9 - 11 pm on the 16th, first Ganymede and then Io will be seen to transit
Jupiter - with their shadows (which are
more obvious) trailing behind - see image
to the right.
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The Planets
ISS - Visible Passes from Bristol
Visible passes of the International Space Station from Bristol during March.
Saturn
Saturn is lying in the southern part of Ophiuchus, 7o up and to the left of
Antares in Scorpius and will begin its retrograde motion westwards across
the heavens on March 25th. It rises around midnight and will be high
enough in the SSE before dawn to make out the ring system which has now
opened out to ~26 degrees - virtually as open as they ever become.
Its diameter increases from 16.5 to 17.4 arc seconds during the month as its
magnitude increases from +0.5 to +0.3. During the month Mars gradually
moves closer to Saturn; initially some 17o down to its lower right, but ending the month just 9o distant. Saturn’s elevation never gets above ~19o and
so the atmosphere will hinder our view of this most beautiful planet.
Uranus
Uranus will not be observable in March – it will reach its highest point in the
sky during daytime and will be low above the horizon at dusk.
Neptune
Neptune will not be readily observable since it will be very close to the Sun,
at a separation of only ~ 1o to 14o from it and will reach its highest point
during daytime
www.jb.man.ac.uk
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www.in-the-sky.org
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www.heavens-above.com
The Early Evening March Sky
This map shows the constellations seen in the South during the early evening, including the prominent constellation of Orion. Moving up and to the
right - following the line of the 3 stars of Orion's belt - brings one to Taurus;
the head of the bull being outlined by the V-shaped cluster called the Hyades, with its eye delineated by the orange red star Aldebaran. Further up to
the right lies the Pleaides Cluster. Towards the zenith from Taurus lies the
constellation Auriga, whose brightest star Capella will be nearly overhead.
To the upper left of Orion lie the heavenly twins, or Gemini, their heads indicated by the two bright stars Castor and Pollux. Down to the lower left of
Orion lies the brightest star in the northern sky, Sirius, in the constellation
Canis Major. Up and to the left of Sirius is Procyon in Canis Minor. Rising in
the East is the constellation of Leo, the Lion, with the planet Saturn up and
to the right of Regulus, its brightest star. Continuing in this direction towards Gemini is the faint constellation of Cancer with its open cluster Praesepe (also called the Beehive Cluster or M44). On a dark night it is a nice
object to observe with binoculars.
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The Late Evening March Sky
This map shows the constellations seen in the south around midnight.
The constellation Gemini is now setting towards the south-west and Leo
holds pride of place in the south with its bright star Regulus. Between Gemini and Leo lies Cancer. It is well worth observing with binoculars to see the
Beehive Cluster at its heart.
Below Gemini is the tiny constellation Canis Minor whose only bright star is
Procyon. Rising in the south-east is the constellation Virgo whose brightest
star is Spica. Though Virgo has few bright stars it is in the direction of a great
cluster of galaxies - the Virgo Cluster - which lies at the centre of the supercluster of which our local group of galaxies is an outlying member.
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‘Sky This Month’ : www.jb.man.ac.uk
Observing Notes
Dwarf Planet 136472 Makemake at Opposition
(22nd Mar at 01:43)
Planetary
Positions
15 March
Makemake is a dwarf planet and perhaps the largest Kuiper Belt Object (KBO) with a diameter that is
about 2/3 the size of Pluto. It has no known satellites, which makes it unique among the largest
KBOs and means that its mass can only be estimated. Its extremely low average temperature, about
30 K (−243.2 °C), means its surface is covered with
methane, ethane, and possibly nitrogen ices.
Makemake was discovered on March 31, 2005 and
its name derives from Makemake in the mythology
of the Rapa Nui people of Easter Island.
136472 Makemake will be well placed for observation, in the constellation Coma Berenices. It will be
visible for much of the night, reaching its highest
point in the sky at around midnight local time.
From Bristol, it will be visible all night. It will become visible at around 19:42 (GMT) as the dusk sky
fades, 25° above your eastern horizon. It will be lost
to dawn twilight at around 04:46, 41° above your
western horizon.
The position at the moment it passes opposition
will be RA 12h55m20s, DEC +25°44', mag. 16.9.
1 March 23:00
15 March 22:00
31 March 21:00
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www.heavens-above.com
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The Sky Looking South at 22:00 mid-March 2016
The Sky Looking North at 22:00 mid-March 2016
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The Sky Looking West at 22:00 mid-March 2016
The Sky Looking East at 22:00 mid-March 2016
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March
TheEquinox
Sky This-Month
Sunday- 20
Perseus
March
The Sky Looking Overhead at 22:00 mid-March 2016
Sunday March 20th is the March equinox, a day when the Sun is above the
horizon for exactly half the time everywhere on Earth. According to the astronomical definitions of the seasons, this day marks the beginning of spring
in the northern hemisphere and of autumn in the southern hemisphere.
On the day of the equinox, the Sun will appear to rise from the point on the
horizon which lies due east, and set beneath the point which lies due west.
This happens as the Sun's annual journey across the sky, through the constellations of the zodiac, carries it across the celestial equator. As a result the
Sun appears directly overhead at noon on the Earth's equator.
Equinoxes occur twice a year – in March and September – once when the
Sun is travelling northwards, and once when it is travelling southwards. The
position of the Sun at the moment of the March equinox is used to define
the zero point of both right ascension and declination.
In practice this is not exactly the case, however, because of a phenomenon
called the precession of the equinoxes. This means that the location of the
equinoxes creep across the sky at a rate of around 50 arc-seconds each year.
Astronomers quote right ascensions and declinations based on the configuration of the Earth's path around the Sun on January 1, 2000.
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www.in-the-sky.org
The Sky This Month - Cancer
The Sky This Month - Cancer
Messier 77 (NGC 1068)
The name ‘Cancer’ means ‘the crab’ in Latin. It is the faintest of the 12 zodiac constellations and contains some famous DSOs: the open cluster Praesepe, aka the Beehive Cluster (M44), and the open cluster M67. Cancer does
not have any stars brighter than 4th mag. Stars α, δ, and γ Cancri lie close to
the ecliptic and can be occulted by the Moon and, rarely, by planets.
Acubens – α Cancri (Alpha Cancri) [SAO 98267]: The 4th brightest star in
Cancer and its apparent mag. varies from 4.20-4.27. It is a multiple star system ~ 174 LY distant. The brightest component (A), is a white A-type main
sequence dwarf. The star has an 11th mag. companion (B) and the brighter
star in the system is suspected to be a very close binary itself, consisting of
two stars separated by 0.1 arc-seconds. Acubens belongs to the spectral
class A5m and has a luminosity of 23 times the Sun.
Al Tarf – β Cancri (Beta Cancri) [SAO 116569]: The brightest star in the constellation, with an apparent mag. of 3.5. It is a binary star that consists of an
orange K-type giant and a 14th magnitude companion 29 arc-seconds away.
Beta Cancri is ~ 290 LY distant.
Asellus Australis – δ Cancri (Delta Cancri) [SAO 98087]: An orange giant
with an apparent mag. of 3.94, 180 LY distant, 2nd brightest star in Cancer
and it marks the location of M44. The star is also notable for its less famous
name, Arkushanangarushashutu, which is the longest of all the known star
names, meaning “the southeast star in the Crab” in ancient Babylonian.
Asellus Borealis – γ Cancri (Gamma Cancri) [SAO 80378]: A white A-type
subgiant ~ 158 LY distant. It has an apparent visual mag. of 4.66.
Iota Cancri (ι Cancri) [SAO 80416]: A double star - the brighter component
is ~298 LY from Earth. - a yellow G-type bright giant with an apparent mag.
of 4.02. The companion is a white A-type main sequence dwarf
with an apparent mag. of 6.57. The 2 stars are separated by
30.6 arc-seconds and are resolvable through a small telescope.
22 [# - Meade LX200 Object Catalogue No.]
M44
M67
NGC 2775
NGC2775
Beehive Cluster (Praesepe, Messier 44, NGC 2632) [M44]: An open star
cluster about 577 LY distant - one of the nearest and most populated open
clusters to the solar system. It has an apparent mag. of 3.7, is visible to the
naked eye and its estimated age is 600 M years. M44 contains at least 1000
stars: 63% are red dwarfs and 30% are Sun-like, classified as F, G and K-class
stars. The brightest stars in the cluster are blue-white in colour and with
magnitudes ranging between 6 and 6.5.
Messier 67 (M67, NGC 2682) [M67]: One of the oldest open clusters
known, with an ~ age between 3.2 and 5 billion years. It has an apparent
mag. of 6.1. M67 contains over 100 stars similar to the Sun and a number of
red giants. Almost all the stars in the cluster are roughly at the same distance and of the same age which makes M67 one of the most studied objects in the field of stellar evolution.
NGC 2775 (Caldwell 48) [NGC2775]: A spiral galaxy ~ 55.5 M LY distant,
with apparent mag. 11.03. It has multiple spiral arms with few HII regions,
which means there was recent star forming activity occurring in it.
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www.constellation-guide.com
The Sky This Month - Canis Major
The Sky This Month - Canis Major
The constellation is home to Sirius, the brightest star in the sky, as well as
several notable DSOs: the Canis Major Dwarf Galaxy, the open cluster M41,
the emission nebula NGC 2359 (also known as Thor’s Helmet), and the colliding spiral galaxies NGC 2207 and IC 2163.
Sirius – α Canis Majoris (Alpha Canis Majoris)
[67]
[62]
[# 067]
Sirius, also known as the Dog Star, is the brightest star in the sky and the 5th
nearest star system to the Sun. Sirius is a binary star with an apparent visual
mag. of -1.42. It is only 8.6 LY distant. The brighter component, Sirius A, is a
white main sequence star and the companion, Sirius B, is a white dwarf that
orbits the primary every 50 years. The distance between the two stars varies
between 8.1 and 31.5 AU. The companion is not visible to the naked eye.
Sirius A belongs to the spectral class A1V and Sirius B to DA2. Sirius A has
twice the mass of the Sun and is 25 times more luminous. Sirius B is almost
equal to the Sun in mass (0.98 solar masses) and is one of the most massive
white dwarfs known. The age of the star system is estimated to be between
200 and 300 M years.
Adhara – ε Canis Majoris (Epsilon Canis Majoris) [# 070]
Adhara is the 2nd brightest star in Canis Major and the 24th brightest star in
the night sky. It is a binary star that lies about 430 LY distant. The primary
component belongs to the spectral class B2 and has an apparent mag. of
1.5. It is one of the brightest known UV sources in the sky. The companion
star has an apparent mag. of 7.5 and is located 7.5’’ away from the primary.
Messier 41 (M41, NGC 2287)
[M41]
M41 is an open cluster located 4 degrees south of Sirius. It is 25-26 LY in
diameter and between 190 and 240 M years old. The cluster contains about
100 stars, with the brightest being a K3-type giant located near the centre of
the cluster. M41 also contains several red giants. The cluster is approximately 2,300 LY distant and has an apparent mag. of 4.5.
24 [# - Meade LX200 Object Catalogue No.]
Sirius A & B
NGC2207
& IC2163
[71]
[72]
[75]
[70]
[60]
M41
Canis Major Dwarf Galaxy: The Canis Major Dwarf Galaxy (CMa Dwarf) is an
irregular galaxy, roughly elliptical in shape, that is believed to be the nearest
neighbouring galaxy to the solar system (~ 25,000 LY distant). The galaxy,
first discovered in 2003, is a difficult object to observe because it lies behind
the plane of the Milky Way, obscured by stars, dust and gas. It is believed to
be severely affected by the Milky Way’s gravitational field.
NGC 2207 and IC 2163: NGC 2207 and IC 2163 are
colliding spiral galaxies in Canis Major. They are
approximately 80 M LY distant and have apparent
mags. of 12.2 and 11.6, respectively. Three supernovae have been observed in NGC 2207 in
1975, 1999 and 2003. The galaxies are in the process of tidal stripping, with the larger galaxy pulling stars and other material from the smaller one.
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www.constellation-guide.com
The Sky This Month - Canis Minor
The Sky This Month - Canis Minor
Gomeisa – β Canis Minoris (Beta Canis Minoris): [# 076]
Gomeisa, the 2nd brightest star in Canis Minor, is a hot, B8-type main sequence star classified as a Gamma Cassiopeiae variable. It rotates rapidly
and exhibits irregular variations in luminosity because of the outflow of
matter. These stars are also known as shell stars because they are surrounded by a disk of ejected material, which is heated up by the stars’ emissions.
[76]
Gomeisa is approximately 170 LY distant. It has a mean apparent mag. of
2.89, with its brightness varying between mags. 2.84 and 2.92.
γ Canis Minoris (Gamma Canis Minoris)
[80]
The brightest star in the constellation is Procyon, Alpha Canis Minoris, which
is also the seventh brightest star in the sky. Canis Minor does not contain
any Messier objects.
Procyon – α Canis Minoris (Alpha Canis Minoris): [# 080]
Procyon has an apparent mag. of 0.34 and is 11.41 LY distant, being the 13th
nearest star system to our own. It is a binary star system, composed of a
white main sequence star, Procyon A, which belongs to the spectral class F5
IV-V, and Procyon B, a DA-type faint white dwarf as the companion. Procyon
A has 1.4 solar masses and is 7.5 times more luminous than the Sun, while
Procyon B has 0.6 solar masses and an apparent mag. of 10.7.
Winter Triangle and Hexagon Asterisms
Procyon is part of the Winter Triangle asterism, along with Sirius in Canis
Major and Betelgeuse in the constellation Orion. It is also one of the vertices
of the Winter Hexagon, along with the stars Capella in Auriga, Aldebaran in
Taurus, Pollux in Gemini, Rigel in Orion and Sirius in Canis Major (see above).
26 [# - Meade LX200 Object Catalogue No.]
[SAO 115478]
Gamma CMi is a double star, a spectroscopic binary, ~ 398 LY from Earth. It
has an apparent visual mag. of 4.33. The main star in the system is an orange
K-type giant and the unresolved companion has an orbital period of 389
days.
Luyten’s Star (GJ 273)
(RA 07h 27m 25s Dec +05° 13′ 33’’)
Luyten’s Star is a red dwarf, approximately 12.36 LY from Earth. It has an
apparent mag. of 9.87 and is a challenging object to observe. Luyten’s Star is
the 22nd nearest star system to our own. The closest approach was about
13,000 years ago, when the star was within 3.67 parsecs. It is now in the process of moving away from the solar system. Luyten’s Star was named after
Willem Luyten, the Dutch-American astronomer who first determined the
star’s proper motion. The star is currently located only 1.2 LY from Procyon.
Deep Sky Objects in Canis Minor
Canis Minor contains a number of deep sky objects, but all are very faint and
difficult to observe. The brightest is the spiral galaxy NGC 2485, with an apparent mag. of 12.4.
The galaxy is located 3.5 degrees northeast of Procyon. Its coordinates are
07:56:48.7 (right ascension), +07:28:39 (declination).
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Society News
Programme of Events 2015-16
(At Bristol Photographic Society, Station Road, Montpelier, Bristol. BS6 5EE )
4 Mar
11 Mar
18 Mar
25 Mar
Gravitational Wave Astronomy (Prof. Mark Hannam)
Telescope Surgery
Observing Planetary Nebulae (Owen Brazell)
Good Friday - no meeting
BAS Committee
The AGM was held on 19th February and the new Committee was elected,
with the following Committee members and roles for the next 12 months:
NAME
ROLE
INFO.
Richard Mansfield
Pete Quin
Simon Perks
Roger Steer
Chair
Vice Chair
Treasurer
Secretary
OFFICERS
Jane Clark
Stephen Price
Fiona Lambert
Allan McCarthy
Sari Vanska
John Bishop
John Huntley
Nigel Kirkland
Rod Davis
Observations Director
Observatory Director
Speaker Secretary
Tyntesfield Coordinator
Member
Member
Member
Member
Member
Richard Mansfield
Stephen Price
Sari Vanska
John Bishop
Membership Secretary
BASIL
Social Media
News & Website
COMMITTEE
NON-ELECTED
ROLES
Bristol Astronomical Society (Registered Charity No. 299649)
www.bristolastrosoc.org.uk
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