“After wondering for some time whether it was possible to image the sky from one morning to the next where I live in Athens Greece, I decided to give it a try. After hours of planning and preparation, and a full day of shooting, the image above is the result of this labor of love. It took me about 12 hours to pull together and process a single image that included over 500 star trails, 35 shots of the Sun and 25 landscape pictures.
I began the shooting the morning of December 30, 2010, taking photos with my camera on a tripod facing east. The day portion of this shoot is composed of a dozen shots covering the landscape from east to west as well as the Sun’s course across the sky, from sunrise to sunset. I recorded the Sun’s position exactly every 15 minutes using an intervalometer, with an astrosolar filter adjusted to the camera lens. In one of the shots, when the Sun was near its maximum altitude, I removed the filter in order to capture a more dramatic shot that showed the Sun’s “glare.” After sunset, I took various shots with the camera facing west-northwest in order to achieve a more smooth transition from the day portion to the night portion of the image. The night portion is also composed of a dozen landscape shots but this time from west to east. After the transition” shots, I took a short star trail sequence of approximately half an hour duration, with the camera facing northwest. At 7:30, I turned the camera to the north and started taking the “all-night” star trail shots — lasting almost 11 hours. After accomplishing this, I then turned the camera to northeast and shot another short half an hour star trail sequence, and then finally, with the camera now facing east-northeast, I took a series of night-to-day transition shots.”
Our Night Sky When We Collide With Andromeda
In the photos above in order:
— Present day
— 2 Billion years from now the of the approaching Andromeda galaxy is noticeably larger
— 3.75 Billion years, Andromeda fills the field of view
— 3.85 Billion years, the sky is ablaze with new star formation
— 3.9 Billion years, star formation continues
— 4 Billion years, Milky Way is warped and Andromeda is tidally stretched
— 5.1 Billion years, cores of both galaxies appear as a pair of globes
— 7 Billion years, the cores have merged, the bright core dominates the night sky
Here is an animation of the collision
In around 4 billion years our galaxy, The Milky Way, will collide with our neighbor galaxy Andromeda or M31. You might think this will be a catastrophic event for everything in the galaxy including our solar system but in reality most of the solar systems will simply pass by each other. However, the gas and dust between the stars will collide and eventually form new stars. Also, the orbits of those solar systems will be changed given the new galactic center(s) and the new mass pulling everything towards it and tossing them around.
The massive Andromeda galaxy is about 120,000 light years across while our galaxy is 100,000 light years across. Given their size, the speed that we our hurdling towards each other is relatively small at 250,000 miles per hour.