Mir and I went on an unexpected aurora chase following the NASTRO meeting last night. Conditions weren't great: an almost full moon washed out the northern sky. If not for that this would have been one the best displays of the year.
Here's a panorama taken from the dunes at Low Hauxley. The lights of Amble on the left and the lighthouse on Coquet Island on the right.
The shimmering activity died away shortly after this picture was taken leaving a steady green arc of light. The picture below was taken near Warkworth from the bank of the river Coquet.
.We're heading towards an equinox so hopefully conditions for aurora chasing will improve and the moon will soon depart the evening sky.
Venus is at inferior conjunction today. That means it positioned between the Earth and Sun.
When the alignment is exact Venus is seen to transit in front of the Sun. At most inferior conjunctions the alignment is not exact and Venus passes above or below the Sun. That was how things were today; Venus passed just under 8 degrees south of the Sun.
Here is the simulated view provided by Stellarium:
It's very difficult to observe Venus under these circumstances. The planet isn't visible to the naked eye. It's so close to the Sun that even when the telescope is aimed at Venus some sunlight can still enter the optical system and cook the inside of the telescope!
I was using a Celestron NexStar 102SLT to observe Venus. The telescope is tracking Venus on the HEQ5 Pro mount. Without being able to do a polar alignment in daylight it was fairly tricky to find Venus. My method was to get the 'scope pointed at the Sun (and then correctly focussed) with a solar filter in place. Then I offset the telescope by the required number of degrees in RA and Dec and hoped for the best after removing the solar filter.
Venus was relatively easy to see once it entered the field of view. A razor sharp white crescent against bright blue sky. The air was a little turbulent and that stopped me getting a good picture with the camera. I did get the crescent though:
Venus has been visible in the evening sky after sunset since late 2014. After today it is technically a morning sky object - visible before dawn. Venus will be shining in the morning sky before sunrise before the end of the month.
I'm giving a presentation at NASTRO in few minutes. The PDF of my talk can be found on my astronomy lectures page. Click here!
During the summer in doesn't get dark in Northumberland; just a lingering twilight after the Sun goes down. This week astronomical darkness has returned and I've started observing and imaging again.
Last night I too this picture of a little twinkly orange star in the constellation Scutum (the Shield).
The star at the centre of the picture is called UY Scuti. It is very dim - a telescope is needed to pick it out of the thousands of Milky Way stars in the same field of view.
However this is no normal star. UY Scuti is a candidate for being the largest star in the entire Galaxy. Astronomers believe the actual size of UY Scuti is as shown in the picture on the right: big enough to hold 5 billion Suns!
The distance from here to UY Scuti is thought to be around 9,500 light-years and we're viewing it through the gas and dust of the Milky Way's spiral arms and that's why it seems to shine so feebly in the night sky. Appearances are often deceptive in astronomy and UY Scuti is actually about 340,000 times more luminous than the Sun. If UY Scuti were to replace the Sun at the centre of the solar system then the Earth would be inside the star. Along with Mars and Jupiter.
Despite all of this UY Scuti is not that massive - only 7-10 times the mass of the Sun. The density of the star is very low and surface gravity at the boundaries of the star are low too. Red supergiants lose material to the wider universe in solar winds a million times more powerful than the Sun produces. At the end of their lives, they all end with a bang as a type II supernova. At our present distance this would make UY Scuti visible to the naked as it temporarily becomes brighter than even Venus can be in our sky.
Dr Adrian Jannetta
Guitar strummin' explorer of the universe. Mild mannered maths teacher by day and astronomer by night.