In case you haven't seen this story, here's something to be aware of through the weekend beside Artemis II. There's a comet approaching the sun this weekend, by the name of MAPS. This comet was discovered on January 13th so 11 weeks ago (this is week 14, it was discovered in week 3). Soon after discovery as the orbit was calculated, it was determined that the comet would make a close approach to the sun, with its closest point - its perihelion - this Saturday, April 4th.
The highlight is that this comet is going to come very close to the sun, and after its closest approach, if it doesn't get ripped apart by the sun, it will be bright enough to see in the daytime which would make it a naked eye object close to the sun in the daytime sky.
Let me fill in some details from Space.com. First off, MAPS seems like an odd name, compared to other comets I've seen. Historical comets like Halley's comet were typically named after the discoverer. That's still pretty typical although more organized than it was in "the old days."
"MAPS" is an acronym using the first letters of the surnames of the discoverers: Alain Maury, Georges Attard, Daniel Parrott, and Florian Signoret. They found the comet using a remotely operated 11-inch telescope at the AMACS1 observatory in Chile's Atacama Desert. What makes this discovery special is that Comet MAPS belongs to a special class of comets known as Kreutz sungrazers. (Pronounced like KROYTZ)
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Saturday, April 4, is the day of Comet MAPS perihelion — when it will make its closest approach to the sun. Based on updated orbital elements published on the Central Bureau for Astronomical Telegrams (CBAT) Circular#5675, Comet MAPS will pass within 101,100 miles (162,700 km) above the sun's surface (the photosphere) at 10:24 a.m. EDT (1424 GMT, 7:24 a.m. PDT). The comet will then be in the midst of completing a hairpin-curved path around the sun, racing at a speed of 322 miles (518 km) per second.
I haven't seen anyone predicting confidently whether or not MAPS will survive its close encounter of the potentially destructive kind, and I wouldn't put much faith in that if they did. I think they'd need to have more knowledge of the comet than exists at the moment. Before you try to see it, you would probably do better trying to follow news online about it. I'll get back to that shortly.
Let me show you a projection for the comets path with times marked around the sun. The approach to the sun starts at the lower left hand part of the picture - you'll note the first point is labelled April 2nd at 1200 UTC. The two dots on upper right of that triangle marking its path are both two days later, April 4th, 0600 UT and 2200 UT, 16 hours later. It exits the path in the picture on the 6th at 0500 UT. You'll note in the center of the image, the orbital path goes over a white circle - that's the diameter of the sun, or about 1/2 degree. The dark circle that image is contained in is the area the telescope has blocked off - to keep the sensor from being burned out.
It is also possible that the comet may become extremely bright around this time, possibly even bright enough to glimpse in the daytime, though the very close proximity to the sun in the sky makes this an extremely dangerous proposition. Indeed, the sun's infrared rays can burn the retina of the eye and cause irreparable damage, all without causing any pain and neither sunglasses, telescopes, nor binoculars will protect against the type of eye damage that could ultimately result in blindness, when a person — however briefly — accidentally looks directly into the sun's rays.
To get a good (and safe) view of Comet MAPS as it approaches and then sweeps rapidly around the sun, reserve a seat next to your computer and stay tuned to SOHO's LASCO (Large Angle and Spectrometric Coronagraph Experiment) C3 camera, by accessing either its near-live images or videos that span the past 24 hours.
The source article at Space.com goes into some inevitable - but pointless IMO - speculation on what could happen during the roughly four days captured in this image. The comet could disintegrate before or just at perihelion (closest approach to the sun), it could disintegrate after perihelion but still close to the sun, or it survives the perihelion and comes out unscathed.
That last alternative is the only one that could give us a great show. The unpleasant reality is we have nothing we can do to influence it. The comet is going to do what it's going to do and not only doesn't care what we see, it's a hunk of ice and rock: it can't care what we see. I'm not sure when the last bright daytime comet was; they mention "The Great Comet of 1965," Ikeya-Seki, which was the most brilliant comet of the 20th century. It attained a magnitude of at least -10 (as bright as a half-moon) and was readily visible next to the sun during the daytime. In 1965, I was first getting interested in watching the night sky and I missed that one, getting a typical beginner's refracting telescope with about a 2" objective about a year after the comet. I've just read about Ikeya-Seki since 1965, much like I got my first shortwave receiver after the best solar cycle in recorded history, cycle 19 in the late '50s.
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