It's lonely out there in the frozen outer solar system. On Saturday, December 9th, that most famous of all comets 1P/Halley reaches a hallmark point on its 75-year journey through the solar system, reaching aphelion or its ...
You could say that December 2023 represents a midpoint between the last 1986 and the next 2061 apparition for the comet. No one has seen Halley's Comet since the European Southern Observatory's Very Large Telescope imaged it a generation ago in 2003. At the time, it was 28 Astronomical Units (AU) distant at magnitude +28.
The exact moment of aphelion occurs at 1:00 Universal Time (UT) on December 9th, (8:00 PM EST on Friday night on the 8th). At that point, Halley's Comet will be 35.14 AU (almost 3.3 billion miles or 5.3 billion kilometers) from the sun. This puts the comet out beyond the orbit of Neptune, shining at +35th magnitude in the southern constellation of Hydra the Sea Serpent. The comet will also be moving at its slowest velocity, at 0.91 kilometers per second or 2,000 miles per hour respective to the sun.
This puts the comet well out of the range of amateur or even large professional telescopes. As of writing this, NASA has no stated plans to image Halley's at aphelion using Hubble or the JWST. Certainly, there would be little scientific advantage at doing this, other than pushing the space telescopes to their limits.
"I took a quick look through approved HST and JWST programs and I do not see any programs planning to observe Halley's Comet, either through imaging or spectroscopy." Christine Pullam (NASA-Space Telescope Science Institute) told Universe Today.