Bootes Constellation

The Bootes constellation represents the herder and is a summer constellation visible from early Spring in the evening sky. Although not a well known constellation it is very prominent with the 4th brightest star and a easily recognisable kite shape. The brightest star also forms part of the spring asterism – the spring triangle and is the constellation closest to the Big Dipper. Although the formation does not clearly reflect its symbolism it does offer a constellation that is relatively easy to identify and visible throughout much of the year to viewers in the northern hemisphere.

The Bootes constellation is one of the original 48 constellations listed by the Egyptian mathematician Ptolemy, who lived under Roman rule in Alexandria in the 2nd century. These constellations formed the basis for the modern list agreed by the IAU. Constellations from the southern hemisphere, unable to be seen from the Mediterranean, represent the majority of additions to the list.

As the earth moves in its orbit around the sun, each night you are looking at a different portion of the sky. When looking at stars it is important to be aware of what is within your view. Northern hemisphere stargazers can group constellations into 3 groups; circumpolar, summer and winter constellations. The circumpolar constellations are in the north sky, appear to move around the north star and are visible throughout the year. The constellations in the south sky are only visible for part of the year and are grouped as either summer or winter constellations. Each is visible from between 4 to 10 months.

It is important to be aware of the specific time of year and hour of the night when deciding what to look for. These pages below show the constellations in each group so you can find the constellations that interest you. 

CIRCUMPOLAR (year around) – Ursa Major – Cassiopeia – Ursa Minor – Draco – Cepheus

WINTER – Pegasus – Pisces – Aries – Auriga – Taurus – Orion – Canis Major  – Canis Minor – Gemini – Lynx – Cancer – Leo – Winter Hexagon

SUMMER – Virgo – Libra – Scorpius – Bootes – Hercules – Lyra – Ophiuchus – Sagittarius – Aquila – Cygnus – Capricornus – Aquarius

Or use this guide to easily see which constellations are easiest to find right now:

BEST CONSTELLATIONS TO FIND THIS MONTH

Bootes Quick Facts:

Symbolism: The Herder

Neighbouring constellations: Virgo (south), Leo (south west), Ursa Major (north west), Drac0 (north), Hercules (north east), Corona Borealis (east)

Brightest star: Acturus, -0.04 magnitude (4th brightest star in the night sky)

Stars brighter than 3 magnitude: 3

Primary stars: 7 (6 in the shape of a kite with 4 stars in each corner and additional stars at the midpoints of the longer sides of the diamond shape. 1 additional star representing the string attached to the kite)

Latitude: 20 – 40 degrees north

Northern Hemisphere Season: Summer (December – September)

Which months can you see Bootes constellation?

Bootes constellation can be seen from December to September but can be found high in the sky at 21:00 during June:

• Early evening viewers (before 21:00) can find the constellation from March in the eastern sky until September in the western sky. Bootes will be visible overhead in June.

• Mid evening viewers (21:00-23:30) can find the constellation from February in the eastern sky until August in the western sky. Bootes will be visible overhead in May.

• Late evening viewers (after 23:30) can find the constellation from January in the eastern sky until July in the western sky. Bootes will be visible overhead in April.

• Early morning viewers can find the constellation from November in the eastern sky to May in the western sky. Bootes will be visible overhead in December.

As time passes the constellation will gradually appear earlier in the night with ranges below showing the window of opportunity in each month. Bootes constellation sits between 20-40 degrees north latitude. Therefore, the further south your position the further north it will appear in the sky. At its maximum range it is possible to see Bootes at latitudes between +90 and -50.

Best time to see Bootes constellation:

Visible throughout the night in April and May

Best visible at 21:00 in June

November: Visible briefly before before sunrise. Appearing on the eastern horizon at 03:30. It will continue moving west until sunrise when it will be 25 degrees above the eastern horizon.

December: appear on the eastern horizon at 01:30. It will continue moving west until sunrise when it will be 60 degrees above the eastern horizon.

January: appear on the eastern horizon at 23:30. It will continue moving west until sunrise when it will be at its peak 80 degrees above the southern horizon.

February: appear on the eastern horizon at 22:00, reaching its peak at 04:00, 80 degrees above the southern horizon. It will continue moving west until sunrise when it will be 65 degrees above the western horizon.

March: appear on the eastern horizon at 20:00, reaching its peak at 02:30, 80 degrees above the southern horizon. It will continue moving west until sunrise when it will be 50 degrees above the western horizon.

April: Visible throughout the night. 15 degrees above the eastern horizon at sunset, reaching its peak at 01:00, 80 degrees above the southern horizon. It will continue moving west until sunrise when it will be 30 degrees above the western horizon.

May: Visible throughout the night. 40 degrees above the eastern horizon at sunset, reaching its peak at 23:00, 80 degrees above the southern horizon. It will continue moving west until sunrise when it will be 15 degrees above the western horizon.

June: 70 degrees above the south east horizon at sunset, reaching its peak at 21:00, 80 degrees above the southern horizon. It will continue moving west until 03:30 when it will begin to be only partially visible on the western horizon.

July: 70 degrees above the south west horizon at sunset. It will continue moving west until 02:00 when it will begin to be only partially visible on the western horizon.

August: 50 degrees above the western horizon at sunset. It will continue moving west until 24:00 when it will begin to be only partially visible on the western horizon.

September: 35 degrees above the western horizon at sunset. It will continue moving west until 22:00 when it will begin to be only partially visible on the western horizon.

October: Briefly visible after sunset. 20 degrees above the western horizon at sunset. It will continue moving west until 20:00 when it will begin to be only partially visible on the western horizon.

Trajectory: The constellation is between 20-40 degrees north which means that many viewers in the northern hemisphere the constellation will pass directly overhead. Its peak trajectory in Wadi Rum is 80 degrees above the southern horizon from January through July.

Not the right time for Bootes constellation? Have a look what constellations you can see tonight.

How to find Bootes constellation?

Difficulty to find: Easy – Difficulty to interpret: Very Hard – Locating asterism: Big Dipper

All of the primary stars in Bootes are above 4 magnitude so can be easily recognised once the constellation is located.

Option 1: Big Dipper 

Bootes is very close to the Big Dipper and the handle of the saucepan can be used to easily locate Bootes and Arcturus. When following the handle away from the pan observe its curvature. Following that curve you will connect with dimmer stars along a similar curve that are part of the Bootes constellation. At the end of this curve is a very bright star that is Arcturus that is the brightest star in Bootes. Arcturus is around double the length of the handle away from the Big Dipper asterism.

Option 2: Spring Triangle

The spring triangle is the combination of the brightest stars in Leo, Bootes and Virgo. If you are familiar with this asterism then the most northern star is Arcturus in the Bootes constellation.

Learn how to form the shape of Bootes constellation

The is little about the shape of the constellation that is representative of a herdsmen. When the history of the constellation is traced it is more practical to understand. With Babylonian records showing that the constellation with Enil who was the king of their gods and the god of farming. This is understandable given the prominence of Arcturus in the night sky in Spring and the proximity of Arcturus to the suns path during the autumn harvest.

This origin of the constellations association with farming was later developed when the Ancient Greek’s who associated Bootes with the neighbouring Big Dipper asterism. The Greeks identified the Big Dipper as a plough and Bootes as a man pushing the plough. This form is easier to visualise with Bootes as a pear shaped human figure with short legs and faint arms pushing the Big Dipper.

These associations with agriculture led Ptolemy and later astonomers to recognise Bootes to represent the herdsmen. For practical purposes it is easier to identify the kite shape and for the imaginative to identify appropriate stars for the arms and legs to visualise Bootes pushing the plough of the Big Dipper.

This explanation will explain the kite to ensure viewers can accurately identify the key stars that make up the constellation and allow you to build on that with your own imagination.

Starting from Arcturus at the base of the kite and working clockwise around the diamond shape of the kite. Remembering that the kite has the traditional diamond shape of 2 shorter sides at the top and 2 considerably longer sides at the bottom. The distance between all the stars is similar (around double the distance between the stars in the handle of the Big Dipper) which makes it easier to follow:

• Arcturus: the brightest star is at the base of the constellation
• Izar, another bright star in the constellation is north east around the same distance as that of the 3 brightest stars in the handle of the Big Dipper and should be prominent
• The next star is a similar distance in the identical direction and forms the left corner of the kite
• Turn right 75 degrees and move a similar distance to find the top of the kite
• Turn right 90 degrees and move a slightly shorter distance to find the right corner
• Turn right in the direction of Arcturus and you will find a star half way between. This is not a direct line as these stars instead follow the curve of the Big Dipper which helped identify the constellation.
• Once you return to Arcturus search south west and there is a bright star half the distance that separates those in the kite and this star represents the string of the kite

The constellation is also sometimes referred to as having the appearance of an ice cream cone.

For those interested to search for the limbs of Bootes and attempt to visualise a herder it is important to have limited light pollution and allow your eyes to adjust to the darkness

If you consider the right and left corners of the kite as the shoulder and the top as a head then you will need to have well adjusted eyes to find the faint stars that represent the arms. The body is broad at the shoulders and narrow at the waist as is consistent with old world depictions and the legs are very short with the one represented by the string of the kite and relatively bright and the other very faint.

Bootes constellation in the Ancient World

Origin of Bootes, Greek mythology and Ptolemy

Earliest records of Bootes as a constellation are from Babylonian times when it represented the supreme Sumerian god Enlil who was also the god of farmers. This constellation is prevalent in the spring night sky but also close to the solar ecliptic in autumn.

The Greek astronomers further developed the constellations association with agriculture through their mythology by identifying Bootes as the inventor of the plough. They visually identified him as pushing the Big Dipper which they recognised as a manual plough.

Ptolomy disassociated the Big Dipper constellation with the plough and instead recognised it as a component of the Big Bear known as Ursa Major. He continued to recognise Bootes in a role as a primary producer however associated him with Canis Major and Canis Minor as a herder.

Main stars in Bootes constellation

Arcturus (-0.04m, 37ly, 16k suns, #4)

Arcturus is from Ancient Greek meaning ‘guardian of the bear’. It is the 4th brightest star with an apparent magnitude of -0.04. The distance from earth is 37 light years. It is more than 16,000 times the size of the sun. As one of the brightest stars in the sky visible for much of the year Arcturus was a prominent navigational star throughout the world. Arcturus marks the bottom of the kite.

Izar (+2.35m, 203ly, double star, #81)

Izar is from Arabic meaning ‘veil’. It is the 81st brightest star with an apparent magnitude of +2.35. The distance from earth is approximately 203 light years. It is a double star, the bigger of which is 36,000 times the size of the sun. Izar is the midpoint star on the left of the longer sides of the kite.

Muphrid (+2.68m, 37ly, double star, #110)

Muphrid is from the Arabic meaning ‘single’. It is the 110th brightest star with an apparent magnitude of +2.68. The distance from earth is 37 light years. It is a double star the bigger of which is 19 times bigger than the sun. Murphid marks the string that is attached to the kite.

Seginus (+3.04, 87ly, 137 suns, #183)

Seginus is said to be a mistranslation into Latin of the Arabic translation of the Greek Bootes. It is the 183rd brightest star with an apparent magnitude of +3.04. The distance from earth is approximately 87 light years. The star is around 137 times bigger than the sun. Seginus marks the right corner of the kite

Deep Sky Objects

Hercules – Corona Borealis Great Wall: This is the largest structure identified. It spans several constellations and is measured at 10 billion light years in length.

Wadi Rum is one of the best locations in the world to see the full beauty of the stars. Combining high altitudes, clear skies and no light pollution. You may be surprised how many stars are visible to the naked eye. Come with us and spend a night under the stars.