Visual Observations of the M87 Jet

We've all heard about the famous jet in M87, but whoever thought it might be visible in an amateur scope? Here's a great observing challenge for your next visit to a good dark sky site.

CCD Image by Dave Healy
Huachuca Astronomy Club

This image of M87 showing the mysterious 'jet' of galactic material spewing out at great speed from the core of the elliptical galaxy also contains several very faint globular clusters (which are the slightly fuzzy star like objects in the halo) associated with M87. The image was taken through a Meade 16-inch at f/6, 30 minute exposure with the ST-8 CCD, and processed in MaxIm DL 2.0 using "digital development" a process like unsharp masking which greatly reduces the enormous range of contrast between the jet and the halo. Three other very small galaxies appear in the image blending in with M87's halo on the lower right. They are, from left to right, UGC 7652, MAC 1230+1221, and MAC 1230+1222. In Megastar 4, no magnitudes are shown for these three galaxies.

Radio image made with the VLA. Radio and optical images of the jet are very similar.

I was able to see the jet in the Meade 16-inch SCT with a 12.4mm Plossl yielding 328X, and it was visible more of the time in a 9.4mm Plossl (423X), while a 6mm Plossl (677X) degraded the view. As before, there was no sign of the jet in the 20mm Nagler Type 2 eyepiece (203X). Thanks to Rich Jakiel for suggesting that I revisit M87 with higher power.

That said, the jet was difficult, being detectable perhaps 20% of the time, and then only in averted vision. Surprisingly, it appeared as a prominent spike for an instant when I first looked with the 12.4mm, then disappeared for a while. The jet faded in and out of visibility and seemed to change in width, but it was always oriented the same way. It didn't "move around."

My notes read, "If it's anywhere, it's pointing slightly to the north of west from the core." Actually I had no idea which direction "north" was at the outset, what with the diagonal flipping the image and the eyepiece oriented at 2 o'clock for comfort. I only later determined direction by moving the scope with the keypad. The M87 image (above) shows the orientation of the jet, but not the way it looks in the eyepiece!

Seeing and transparency were both good to very good at our southeast Arizona site. I did the full dark-adaptation drill, minimizing time in the sunlight yesterday and hanging out in the observatory (eye patch and all) for more than an hour before attempting to look with the Plossls. M87 was at and just past the meridian when I observed it.

If I could see the jet in a 16-inch, it probably won't require someone with Steve O'Meara's eyesight to see it in a 14-inch or even a 12-inch, given a dark site. - Dave Healy

Regarding M87 and seeing the jet, I did the following observation June 10, 1994 (boy, time flies--seems like last year):

12.5 inch f/6.1 Dob from the Colorado Rockies (about 9000 feet), very dark site.
Magnifications: 70, 98, 158, 280, 408x
Faintest star (in NGC7031): 16.3 > 50% time at 280x.

I did not know the direction of the jet (I did this on purpose so I would not have any bias).

The jet was visible at 280x 20% of the time. At 408x, it was visible 50% of the time. I made a drawing and later checked it against photos and the orientation was right on. The length observed was about 0.5 arc-minute long and only a few arc-seconds wide. - Roger Clark