Daily Archives: July 26, 2017

The Andromeda Galaxy

Posted on by
Reply
The Andromeda Galaxy

The Andromeda Galaxy (M31)

  • Telescope: Stellarvue SVA130T-IS
  • Mount: Losmandy G-11 with Gemini 2 controller
  • Autoguiding: Yes (sub-arcsecond rms accuracy)
  • Optical Configuration: 0.72x field flattener & reducer (f/5)
  • Camera: Canon 60Da
  • Light Frames: 12, 5-min. exposures stacked
  • Calibration: None (no darks, no flats, no biases)
  • Exposure Time: 60 min. (12 x 5 min.)
  • ISO: 800
  • Processing: Photoshop CC
  • Imaging Location: Sierra Nevada Mountains (Altitude: 8,600 ft.)

The  Andromeda Galaxy (M31) is about 2 1/2 times larger than our Milky Way and contains an estimated 1 trillion stars. At a distance of 2.5 million light-years, it is our nearest galactic neighbor and getting closer to us every day at nearly 70 miles per second. But even at that speed, our galaxy won’t collide with Andromeda for at least another 4 billion years. So don’t hold your breath.

North America Nebula

Posted on by
Reply
North America Nebula

North America Nebula (NGC7000)

  • Telescope: Stellarvue SVA130T-IS
  • Mount: Losmandy G-11 with Gemini 2 controller
  • Autoguiding: Yes (sub-arcsecond rms accuracy)
  • Optical Configuration: 0.72x field flattener & reducer (f/5)
  • Camera: Canon 60Da
  • Light Frames: 12, 6-min. exposures
  • Calibration: None (no darks, no flats, no biases)
  • Exposure Time: 72 min. (12 x 6 min.)
  • ISO: 800
  • Processing: Photoshop CC
  • Imaging Location: Sierra Nevada Mountains (Altitude: 8,600 ft.)

The aptly named North America Nebula (NGC7000) in the constellation Cygnus is an emission nebula containing gasses that glow red or blue. The red color comes from hydrogen gas that absorbs light from nearby stars and re-emits it in the red part of the spectrum (hydrogen-alpha emission). The blue light comes from oxygen gas, which also absorbs nearby starlight but re-emits it in the blue. The effect creates a purple haze glowing amid thousands of stars.