Sunday evening. The clouds break as twilight falls. The brightest stars are visible. In the north, noctilucent clouds begin to shine. In the deepest part of the night the Milky Way is visible despite the lingering twilight. Six weeks after the solstice and it's becoming possible to do astronomy again.
This is the view from my garden in Red Row, Northumberland. Light polluted and not completely dark. But so many stars!
Adrian Jannetta writes...
It's turning out to be another good season for noctilucent clouds! NLCs, for short, are the highest clouds on the atmosphere and are formed by water vapour condensing onto meteor smoke about 50 miles above the ground. They are a strictly summer phenomenon (end of May to start of August) and they only form near the poles of our planet. In Northumberland we are in a perfect position to see them each year. I've written a more detailed article about NLCs here. A history of observation and photos of NLC types can be seen here.
NASA produce an up-to-date image of NLC coverage - click here. A clear night doesn't guarantee seeing NLCs but it's always worth a look outside, about 90 minutes after sunset at this time of year. Look towards the northern horizon. You might mistake NLCs for cirrus clouds at first but the white or electric blue colour will grow brighter as the sky around them darkens.
Here are some pictures I've taken in the last week or so.
NLC season should last another 2-3 weeks but NLC appearances will soon begin to diminish as the upper atmosphere heats up again towards the end of summer.
Adrian Jannetta writes...
It's been quite a few weeks since I did a talk at NASTRO. Real life stuff and travelling to Malaysia and Singapore got in the way. The astronomy part of me never switches off though. Stamding at the top of Marina Bay Sands with the stunning vista of the Singapore skyline around me....I was the only idiot looking up at the sky for my first view of alpha Centauri and hoping the cloud in front of the Southern Cross would hurry up and shift. And all the while wishing they'd switch the bloody laser show off. They really haven't heard of light pollution in Singapore.
Next Thursday (July 10th) I'm back at NASTRO and doing another part of my introduction to astronomy course. This time it's cosmology. Much of modern cosmology is entirely uncontroversial: that the universe has a finite age and that the Big Bang model accounts for the expansion, composition and structure we see today. Detailed analysis of the cosmological data suggests that much of the mass in the universe is in a form which doesn't shine or interact with normal matter (so-called dark matter) and that the universe expansion is actually accelerating, driven by a so-called dark energy whose origin and precise nature is not understood. A minority of scientists think the problems of not yet finding direct evidence of dark matter or having to introduce dark energy into cosmological equations can be resolved if we accept that gravity begins to behave differently on the largest scales imaginable.
I hope to touch on all of these issues during the lecture on Thursday. Most people I've met want to know about why the universe looks the way it does. Maybe it's basic human curiosity to know that answer or a deeper need to understand one's place in the universe. Either way, we are all fortunate to be living in a golden age of cosmology where not only can we ask the big questions, but there is hope we can finally learn the answers.
Dr Adrian Jannetta FRAS
Amateur astronomer and mathematics teacher. Guitar strumming explorer of the universe!
Proud nerd and founder of the school space club. A young whippersnapper with a bucket-load of passion.