Where can I find 17P/Holmes in the sky? I live in NJ, USA.?

Answer 1

High in the northeast very close to the star Mirfak, the brightest star in Perseus. About half way between the big M shape of Cassiopeia far to the left and the teeny weeny little dipper shaped Pleiades star cluster far to the right. Do not confuse Mirfak with the much brighter star Capella, which will be much lower in the sky almost directly below in Auriga. I was unable to see it without binoculars at my suburban home, but 7x35 binoculars showed it easily. Oddly, 10x50 binoculars barely showed it at all. In a dark rural sky it should be a naked eye object.

Answer 2

Name: 17P Holmes
Object type:short period comet
Semimajor axis: 3.6174 AU
Eccentricity: 0.43242
Inclination: 19.113 degrees
Longitude of ascending node: 326.867 degrees
Argument of perihelion: 24.259 degrees
Time of perihelion : JD 2454225.0 (12h UT, 4 May 2007)
Perihelion distance: 2.0532 AU
Orbital period: 2513 days

Holmes was closest to Earth on November 4th, when it was 1.6147 AU from us.

Here's an ephemeris for Holmes that I generated from the above orbital elements. Right ascension and declination are like longitude and latitude for the sky. You use those numbers with a star atlas to find what you're looking for.

Year = 2007...
DATE, distance, right ascension, declination
12nov, 1.622 AU, 3h 28m 47s, +50d 26' 35"
13nov, 1.623 AU, 3h 27m 33s, +50d 23' 50"
14nov, 1.626 AU, 3h 26m 20s, +50d 20' 42"
15nov, 1.628 AU, 3h 25m 06s, +50d 17' 13"
16nov, 1.630 AU, 3h 23m 52s, +50d 13' 23"
17nov, 1.633 AU, 3h 22m 41s, +50d 09' 13"
18nov, 1.636 AU, 3h 21m 29s, +50d 04' 42"
19nov, 1.640 AU, 3h 20m 18s, +49d 59' 51"
20nov, 1.643 AU, 3h 19m 08s, +49d 54' 40"
25nov, 1.664 AU, 3h 13m 33s, +49d 24' 15"
01dec, 1.697 AU, 3h 07m 40s, +48d 39' 03"
15dec, 1.808 AU, 2h 58m 32s, +46d 30' 05"

Year = 2008...
DATE, distance, right ascension, declination
01jan, 1.997 AU, 2h 57m 02s, +43d 44' 36"
15jan, 2.190 AU, 3h 02m 54s, +41d 45' 12"
01feb, 2.455 AU, 3h 16m 41s, +39d 52' 28"
15feb, 2.690 AU, 3h 32m 04s, +38d 45' 11"
01mar, 2.948 AU, 3h 51m 28s, +37d 53' 12"
15mar, 3.188 AU, 4h 11m 30s, +37d 17' 37"

For reference, the position of Alpha Persei, or Mirfak, is
RA = 3h 24m, dec = +49d 52'

I went outside and found Holmes just now. It's dimmer than it was a week ago. Look at Mirfak, or Alpha Persei, and you can't miss it. There's sort of a little McDonald's Arch made of dim stars that horseshoes Mirfak, and the comet is below the right foot of the arch (as you look at it archwise).

Answer 3

Look high in the northeast not long after sunset. If you know the sky, it's roughly halfway between the Pleiades and Cassiopeia.

It's getting dimmer day by day, so don't wait. And take a pair of binoculars!

Answer 4

Try this.
http://www.spaceweather.com/images2007/15nov07/skymap_north_holmes.gif