Galaxy with supernova in Leo
The galaxy NGC 3643 is a small and faint object, and at magnitude 14.6 it will be a challenge to see through a medium-sized telescope. On April 21, a supernova was discovered on the outer edge of this galaxy, SN 2020hvf. This picture, taken about 2 weeks after the discovery date, shows that the supernova is brighter than the entire rest of the galaxy combined! I estimate the brightness of the supernova to be about 13.5. When a supernova is brighter than its galaxy, that’s one big explosion!
There is a large elliptical galaxy NGC 3640 near the upper edge of the field. Looking closely, you can see an oddly shaped faint halo, roughly rectangular in shape and not centered on the brightest part of the galaxy. I have never seen a galaxy with a shape like this, and don’t know what to make of it.
To the left of center in this image is a short diagonal line, which is probably a passing asteroid.
| Magnitude | 14.6 |
| Apparent Size | 0.9' x 0.7' |
| Distance (light yrs) | 85 million |
| Right Ascension | 11:21.4 |
| Declination | +03 01 |
| Field of View | 29' x 22' |
Image details: Exposure times of 33 minutes luminance, and 18 minutes each of red, green, and blue, taken with an SBIG STF-8300M imager and a 14" Meade LX850 telescope at f/6.
May 21, 2020