Shield is a very small constellation of the southern hemisphere, located near the celestial equator and visible at latitudes from +80 to -94 degrees. It is well visible from the territory of Russia. The area occupied by the Shield is only 109.1 square degrees (0.26% of the night sky), which corresponds to the 84th largest position among the 88 officially known constellations.
The shield cannot boast of bright stars, asterisms or luminaries of navigational significance, but it still contains several interesting astronomical objects. It is especially noteworthy that the constellation is located within one of the densest zones of the Milky Way.
General description and photo of the Scutum constellation in the sky
The international Latin name for this constellation is Scutum (translated as "shield"). It is currently part of the Hercules group. Scutum is one of two constellations named after real people (the other being Coma Berenice).
The shield has only 20 faintly visible luminaries, which can be seen with the naked eye only inperfectly clear night sky. But within the constellation you can see the famous open clusters (the so-called star clouds). You can see them more carefully with binoculars or a telescope.
Approximately 270 stars in the constellation Scutum have been detailed and described using satellite systems. Among them, there are ten main ones. Since the difference between the degree of removal of different Scutum stars from the Earth is too large, it is impossible to calculate the distance to the Shield arithmetically.
In the photo, the constellation Scutum looks like a small random cluster of luminous dots that do not form a geometric figure. Full visibility is possible in latitudes south of 74 degrees. The best time to observe the constellation is July.
Location in the firmament
The location of the constellation Scutum in the sky belongs to the fourth quadrant of the southern hemisphere (SQ4) and is included in the rich zone of the Milky Way. The value of right ascension (the coordinate that determines the position of a celestial body) is 19 hours. A schematic representation of Scutum in the sky resembles a shield, the tops of which are the brightest stars.
Shield neighbors three constellations:
Vega is a star much higher than Scutum.
To visually determine where the constellation of the Shield is located, you need to look along the Milky Way to the south in the direction of the constellation Aquila, alphaand whose lambdas are located on a straight line pointing to the desired object.
Shield is not among the constellations described in the ancient astronomical map of Ptolemy. This object was designated only in 1864 by the Pole Jan Hevelius and after 6 years was added to the celestial atlas "Uranography". Since then, the Shield has been included in the group of 88 officially designated constellations.
The origin of the name is associated with a historical event - the victory of the Poles over the Turks in the Battle of Vienna, which took place in 1683. The astronomer named the constellation "Shield of Sobieski" in honor of the commander who led the battle, who was also the king of Poland.
The shield contains a relatively small number of stars, of which only 20 can be seen with the naked eye. The brightest luminaries have the fourth and fifth magnitudes. Major stars include Alpha, Beta, Zeta, Gamma, Delta, Eta, Epsilon, R, S, and PSB.
Scutum's brightest star, with an apparent visibility magnitude of 3.85, is Alpha, otherwise known as Janina. It is removed from the Sun at a distance of 53.43 light years. The second place in brightness belongs to the beta of the Shield. The dimmest star visible to the naked eye is HD 174208 at magnitude 5.99, which is close to the line of sight.
Scutum's farthest object is HIP 90204, 326163.3 light-years from the Sun.
|Alpha||The absolute magnitude is -0.08, refers tospectral type K (orange giant)|
|Beta||It is a multiple system, among which there are 2 main objects - A and B beta. The first star is a yellow class G giant, and the second is a blue-white luminary. The total magnitude of Beta is 4.23m. This system used to be called 6 Aquilae|
|Zeta||Remote at 207 light-years from the Sun, a yellow giant classified as G9 IIIb Fe-0.5. The apparent apparent magnitude of this star is 4.68|
|Gamma||A white A1IV/V star of magnitude 4.67, 291 light years away from Earth. It is the fourth brightest luminary of Scutum|
|Delta||The famous giant variable pulsating star (it is the first object of this type discovered in the sky). Stars of this class are otherwise called dwarf Cepheids, the peculiarity of which is that the surface pulsations occur both in longitudinal and transverse directions. Delta belongs to the spectral type F2 IIIp (yellow-white giant) and has an apparent apparent magnitude of 4.72 with a periodic brightness change of 0.2. The star has two satellites and is 202 light-years away from the solar system.|
|This||An orange giant whose diameter is 10 times that of the Sun, and its mass is 1.4 times. Belongs to the spectral type K1III and has an apparent magnitude of 4.83.|
|Epsilon||Multi-stellar system at magnitude 4.88, 523 away from Earthlight years. According to the spectral classification, it belongs to the G8II group, corresponding to bright yellow giants.|
|R||The yellow supergiant, classified as RV Tauri, is the brightest variable in this group with an apparent apparent magnitude of 4.2-8.6. Luminosity variations occur as a result of radial surface pulsations. The star is 1400 light-years from the Sun.|
|S||The red giant, a type of carbon star, has an apparent magnitude of 6.81. The star is 1289 light-years away from Earth|
|PSB B1829-10||A magnetized spinning neutron star of magnitude 5.28, 30,000 light-years away from the solar system. It is a pulsar emitting a beam of electromagnetic radiation. The mass of this star is 1.4 times that of the Sun.|
Scutum also includes the largest star known to date - UY Shield. Its radius is 1708 times larger than that of the Sun.
Notable astronomical objects
Interesting objects of the deep sky in the constellation Scutum primarily include star clusters of various nature. In a clear night sky, some of them can be seen even without binoculars. These are the so-called famous clusters Messier 11 and 26, otherwise known as large star clouds.
Besides them, Scutum includes:
- 2 globular clusters;
- 145 nebulae (52 planetary, 91 dark and 3 diffuse);
- 19 open clusters.
Wild Duck is the name given to the open cluster Messier 11, which is one of the densest open star clusters and contains 2900 stars. The apparent magnitude of this deep sky object is 6.3. The cluster is 6,200 light-years from the solar system. When viewed through binoculars, the object looks like a small foggy cloud with a well-defined core.
The name of the cluster was due to the fact that its brightest stars form a figure resembling a flock of flying ducks. The object was discovered in the 17th century by Gottfried Kirch and entered into Messier's catalog 83 years later.
Compared to the Wild Duck, contains a significantly smaller number of stars (90), which fit in an area with a diameter of 22 light years. The cluster was discovered by Charles Monsieur in 1764. The distance of the object from the Sun is 5 thousand light years.
The cluster looks like a small dense grouping with a rarefied zone in the center. The low density in the core of the cluster may be due to the accumulation of dark interstellar matter on the observation path between the cluster and the Earth. The total magnitude of the cluster is 8, and the brightness of the brightest star within it is 11.9.
Globular Cluster NGC 6712
It is rather large and contains about a million stars, the total brightness of which is 8.1m. The object was first discovered in 1749, but as a globular cluster it wasclassified only in the 1930s.
The physical diameter of this cluster is 64 light years.