Practical problem: Observing competition –

planetarium round

Earth

Mars

Practical problem: Night observation

The Little Dolphin

Determining declination

The Little Dolphin

Draw as the view of the constellation Delfinus (Del) through the finder scope.With an arrow, mark the apparent direction of motion of the stars across the field of view of the finder scope caused by the rotation of the Earth.

Label the stars with the Bayer designations given on the map (α, β, γ, δ and ε).

Also label the brightest of these 5 stars “mmax”.

Also label the faintest of these 5 stars “mmin”.

Draw as the view of the constellation Delfinus (Del) through the finder scope.

•all 4 stars of the parallelogram (1)•the 'tail' (1)•correct scale (1)•correct shape (1)•additional field stars (1)

With an arrow, mark the apparent direction of motion of the stars across the field of view of the finder scope caused by the rotation of the Earth. (2)

Label the stars with the Bayer designations given on the map (α, β, γ, δ and ε). (1)•Also label the brightest of these 5 stars “mmax”. (1)•Also label the faintest of these 5 stars “mmin”. (1)

Draw the view of the Little Dolphin through the larger telescope.

all 4 stars of the parallelogram (4)the 'tail' (1)correct scale (1)correct shape (1)additional field stars (1)

With an arrow, mark the apparent direction of motion of the stars across the field of view of the finder scope caused by the rotation of the Earth. (2)

Label the stars of the Little Dolphin α′, β′, γ′, δ′ and ε′ such that they match the labels of the stars in the constellation Delfinus as given on the map. (3)

Label the brightest of these stars “mmax”. (2)

Determining declination

Tip 1 (if leaders want it!)

The coordinates of the object can be estimated by measuring the time of transit between the lines of the reticle. Adjust the position angle of one arm of the reticle to be parallel to the pair of stars S1 and S2.Measure the time difference between the moment when the pair S1-S2 crosses the line and the moment when Sx crosses it.You can measure the time between transits of star S1 and the line S2-Sx in the same way.

Tip 2 (if leaders want it!)

One arm of the cross is parallel to the direction S1-S2. Start measuring when S1 is in the centre of the cross.

ΔtX is the time taken by Sx to transit between the two arms of the cross.

Δt2 is the time taken by S2 to move from one arm to the second arm of

the cross.

Finding objects on the sky (reserve question)

Using the refracting telescope and setting circles find the following objects on the sky.

Please call the Jury after putting each of objects in the field of view. Write down the telescope coordinates of each object.