IYA Live Telescope Today – Alpha Crucis: Split! and M11

Article written: 28 Mar , 2009
Updated: 24 Dec , 2015
by

If you didn’t get a chance to watch the IYA telescope “live” on Galactic TV today, don’t worry. We took a video capture for you. Step inside to enjoy today’s view of Alpha Crucis, better know as Acrux. Thanks to a little “fine tuning” we’ve learned how to split the doubles on video! As an added weekend treat we’ve even done a little duck hunting, too… Double your pleasure, double your fun… Catch a double star and two videos – instead of just one!

The following information is a cut and paste from Wikipedia to accompany the video:

Alpha Crucis – Acrux: CRUX

Acrux (Alpha Cru / Alpha Crucis) is the brightest star in constellation Crux, the Southern Cross and, at visual magnitude 0.77, is the twelfth brightest star in the night time sky. Acrux is the southernmost first-magnitude star, just a bit more southerly than Alpha Centauri.

Acrux is a multiple star located 321 light years from the solar system. Only two components are visually distinguishable, Alpha 1 and Alpha 2, separated by 4 arcseconds. ?1 is magnitude 1.40 and Alpha 2 is magnitude 2.09, both hot class B (almost class O) stars, with surface temperatures of about 28,000 and 26,000 kelvins respectively. Their luminosities are 25,000 and 16,000 times that of the Sun. Alpha 1 and Alpha 2 orbit over such a long period that motion is only barely seen. From their minimum separation of 430 astronomical units, the period is at least 1,500 years, and may be much longer.

Alpha 1 is itself a spectroscopic binary star, with its components thought to be around 14 and 10 times the mass of the Sun and orbiting in only 76 days at a separation of about 1 AU. The masses of Alpha 2 and the brighter component of Alpha 1 suggest that the stars will someday explode as supernovae. The fainter component of Alpha1 may survive to become a massive white dwarf.

Another class-B subgiant lies 90 arcseconds away from triple Acrux and shares Acrux’s motion through space, suggesting it may be gravitationally bound to Acrux. However, if it is indeed located near Acrux, it is under-luminous for its class. It is probably just an optical double star, most likely several hundred light years beyond Acrux.

(Information Source: Wikipedia)

Wild Duck Cluster (M 11): SCUTUM

The Wild Duck Cluster (also known as Messier 11, or NGC 6705) is an open cluster in the constellation Scutum. It was discovered by Gottfried Kirch in 1681. Charles Messier included it in his catalogue in 1764.

The Wild Duck Cluster is one of the richest and most compact of the known open clusters, containing about 2900 stars. Its age has been estimated to about 220 million years. Its name derives from the brighter stars forming a triangle which could represent a flying flock of ducks.

(Information Source: Wikipedia)

As always, you can visit the remote telescope by clicking on the IYA “LIVE Remote Cam” Logo to your right. We’ll be broadcasting whenever skies are clear and dark in Central Victoria! Enjoy….


5 Responses

  1. Scott Hudson Riley says

    could some educate me on what i am looking in the second video? Is some thing moving or is it something that we don’t get to see to often?

  2. Maxwell says

    The video is a recording from the IYA “LIVE Remote Cam” …the cam streams live when the telescope is operational, that vid was just a clip from that live stream when the telescope was looking at the cluster.

  3. Martin says

    That outlier is not the companion. From the spectral type it is too faint and further away and thus an optical double.

    Martin

  4. Vino says

    Hi Scott!! The second video is of an open cluster… These are group of stars which are gravitationally bound with each other.. The group is moving because we are looking at a telescope in-live.. So the cluster is moving in our field of view…It is the group itself which is very spectacular to look at….

  5. star-grazer says

    It is quite interesting how a bunch of ‘sibling’ stars can stay together for so long- it makes me wonder how long our Sun stayed with its’ ‘siblings’ before going alone on the great journey and time about the great Milky Way galaxy……….

Leave a Reply