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Daily Guide to Comet PANSTARRS

This page is your daily guide for how to find and see Comet PanSTARRS, more accurately known as Comet C/2011 L4 PanSTARRS, which will be visible in the northern hemisphere through spring 2013, but will peak in brightness around mid-March.  To see the guides from past dates, click here.

What it was like to see the comet on March 13 (with pictures).

What it was like to see - errr.. photograph the comet on March 19 (with pictures)

To begin, I have some thoughts about PANSTARRS and its coverage in the media here.  To summarize that quickly, the predictions for this comet are technically 'naked eye' but as you can see from the graphics below, you will also be looking into the twilight of the setting Sun.  Photos from the southern hemisphere show a wonderfully bright comet, but remember that a camera picks up a lot more photons and can see dimmer objects than your eye.  Also, photo manipulation software can boost contrast and make the comet appear brighter and the sky darker.  That said, you MAY be able to see this comet quite well.  It really will depend on your local conditions.  Ideally, you will need the following:

  • A flat, unobstructed western horizon
  • Very clear skies
  • Skies with low humidity to the west

You may also wish to have the following with you:

  • A set of 7x35 or larger binoculars
  • A camera capable of taking timed (i.e., more than 1/4 of a second) photos.
  • A short focal length (wide / rich field) telescope

The PREDICTED brightness of the comet each day is listed below.  It may be brighter or dimmer; comets are notoriously unpredictable.  The graphics below show the sky as seen:

  1. 30 minutes exactly after sunset
  2. From 40 degrees north latitude
  3. With a mostly unobstructed view to the west

For views on where the comet should be compared to looking directly west, at exactly 30 minutes past sunset, and assuming a mostly clear, western horizon, please click here. 

How to measure distance in the night skyThe graphics on this page and the one above are made for observers at or near 40° north latitude. South of that, the comet will appear slightly higher above your horizon early in the month than what these graphics show. If you observe it from north of 40°, the comet will appear even lower in early March than shown, but higher than these as it dims after the middle of March.

THE GRAPHICS ON THIS PAGE DO NOT SHOW THE LANDSCAPE.  They are designed to show you where the Sun is, where the comet is, and where a perfectly flat horizon would be in comparison at specific times (see lower right hand corner of each graphic for exact time and comet magnitude).  You can learn to estimate distance in the sky here, or see the graphic at right.  Bear in mind also that the Earth rotates 15 degrees every hour, so at 30 minutes past sunset, you have less than 30 minutes for several days, and at best, 40 minutes when the comet reaches 10 degrees of elevation.

A comet has its light spread out over a bit of area, unlike stars, which are point source objects.  So the magnitude - or brightness - indicates the total brightness over the whole area of the comet, including the tail, currently estimated at 1 to 2 degrees long (as of early March).  For comparison, most stars in the Big Dipper (look to the NE sky) are around 2nd magnitude.  The two brightest stars in Orion (SW sky) are 1st magnitude.  And remember you'll be looking at the comet into the direction of the sun's twilight, so it will be a bit like viewing a flashlight while looking in the direction of the Sun during the day - visible, but likely not brilliant or dazzling.  It will likely be naked-eye under ideal conditions, but it may take some effort, clear skies, and a great horizon for the best views.  

Here are the daily MEASURING graphics for where to see Comet PANSTARRS (for landscape views, see here). Note that the comet location is listed with a circle, NOT a comet-shape, as that will vary by day.  The graphics simply show the location to look, both in relation to due west, and elevation off the horizon.  Feel free to copy/print these graphics in color ( but for personal use only).

Each chart shows the comet's location at a precise time past sunset - you local sunset time may vary, but the number of minutes past sunset for you to view will not change.  Many observers have not spotted the comet until 40 to 45 minutes past sunset, so it may be lower when you spot it.  USE BINOCULARS.  Measure where the Sun is (estimating based on the strongest "twilight glow"), then measure left or right of that, and then up off the horizon to determine where to see / observe with binoculars / photograph to try and find the comet.  To see the guides from past dates, click here.

Use binoculars, measure carefully, and see what you can find.

March 31, 43 minutes past sunset

Comet PANSTARRS March 31 at 43 minutes past sunset

April 1, 2013

April 2, 2013

April 3, 2013

April 4, 2013

April 5, 2013

To see the guides from past dates, click here.

This page will show graphics for the comet through April 5, 2013.