Some interesting new information has emerged on Betelgeuse, the red supergiant that marks the left ‘armpit’ of Orion the Hunter.
1. It’s still burning Helium in its core so unlikely to go supernova until around 100,000 years.
2. It’s not as massive as previously thought. Earlier studies had shown its radius would extend to the orbit ofJupiter if placed in our solar system. This new data suggests its real radius is 60% of this.
3. It’s closer to Earth than previously measured, at 530 light years. This is 25% closer than we previously thought.
New data published in the Astrophysical Journal. Further reading here.
See a supernova explosion in a distant galaxy over 50 million light years away.
Berto Monard witnessed Supernova 2015F in spiral galaxy NGC 2442 in March 2015, although the actual event happened 50 million years ago, long before human beings inhabited planet Earth.
Supernovae like this produce so much light energy they can briefly out shine the accumulated light from the entire galaxy. For this reason they can be witnessed even with moderately sized back garden telescopes, if you’re lucky enough to be pointing in the right direction at the right time!
Video Credit & Copyright: Changsu Choi & Myungshin Im (Seoul National University)
Source: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
The Milky Way over the Callanish Stones on the Isle of Lewis. Jupiter and Saturn can be seen in this shot low above the horizon. By Emma Rennie of Callanish Digital Design. www.callanishdigitaldesign.com
Another stunning Milky Way shot by Christopher Cogan taken from Muie in Sutherland in the far north of Scotland.
Two stunning Milky Way images taken last night from the Scottish Highlands (and Islands). Both show the bright region of the Milky Way in the vicinity of the Summer Triangle, looking south.
If you imagine our Milky Way as a vast disk of stars, these views are peering further ‘into’ the disk, where the density of stars and stellar matter is greater, and hence brighter. Contrast this with the fainter regions we see in Winter near Orion, when we peer ‘out’ of the galactic disk.
The dark lanes you can see are part of the Cygnus Rift – a region containing vast clouds of dust that obscure some of the light from the billions of stars in the background.
With the Moon well out of the way and proper darkness returning late at night, now is a great time to go out and see the Milky Way for yourself.
Image Credit: R. Corradi, Nordic Optical Telescope
I recently stumbled across this stunning image of the famous Cat’s Eye nebula. It’s a false colour enhancement showing the extended ejecta from the dying star, imaged by the Nordic Optical Telescope on the Canary islands..
The cat’s eye is dubbed a ‘planetary nebula’. An erroneous label as this has nothing to do with planets whatsoever. Rather these nebulae are the beautiful symmetries left behind when stars of similar mass to our Sun enter their final gasps of life. Before collapsing down to a white dwarf (a compact star held in place by electron pressure), the star sheds its atmosphere is great puffs, producing these ghostly but beautiful clouds of ionised gas.
The outer gaseous tendrils seen in this image extend almost 3 light years across and probably represent earlier and more transient episodes of stellar influenza, before the star began its collapse in earnest.
Image Credit: R. Corradi, Nordic Optical Telescope
A direct image of an alien solar system orbiting a Sun like star, over 300 light years away!
I remember growing up in the 1980s hearing about the ‘high probability’ that other stars had orbiting planets, but there was very little evidence then, only some tantalising hints from the gravitational wobbles observed from specific stars.
Since then thousands of new exoplanets have been confirmed using the transit and radial velocity detection methods. I wrote a blog article about this a while back.
These methods are indirect ways of determining the existence of planets, and it’s very rare to actually be able to ‘see’ the planets themselves.
This image is therefore pretty incredible and for me suddenly normalises the idea that these star systems are real places we could, theoretically at least, visit in the distant future.
The image was captured by the European Southern Observatories Very Large Telescope and shows a young Sun like star (only 17 million years old) with two clearly defined giant planets in orbit. (The dots of light closer to the star are background stars and therefore not part of this particular planetary system)
These planets orbit the star at 160 and 320AU (1 AU is the Earth to Sun distance) so they’re much further away from the star than any planet in our solar system.
An example of gamification in one of my recent projects called Stellar Evolver (with audio voiceover). This is a fully VR ready experience and will enable players to interact with and watch the evolution of star systems using the visceral mechanics and feedback of a 3D based shooter.
Stellar systems can evolve from simple proto-planets up to red dwarfs and larger giant stars, eventually culminating in the formation of neutron stars and black holes.
Clearly the overall dynamics, scale and time is being exaggerated here for playability. I hope to demonstrate a working multiplayer prototype at the 2021 Hebridean Dark Sky Festival.
A video of Sirius (the brightest star in the night sky) twinkling on the horizon, captured by Steve Brown @sjb_astro. Many people think they’re seeing a low altitude aircraft or UFO when they witness this.
This phenomenon occurs (to a lesser extent) with any bright star low on the horizon due to the vast amount of atmosphere you’re seeing it through. As stars gain elevation, and less atmosphere is between us and them, they shine more steadily, and views are hugely improved.
The difference in the amount of atmosphere you look through with elevation is very striking (as demonstrated in the sketch below). Particularly for faint deep sky objects like galaxies, high elevations makes a dramatic difference to the quality of visual or photographic images you’ll collect.
How much atmosphere you look through with observing angle. At the zenith (overhead) you look through over 2/3 less atmosphere than at the horizon.