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Designed to study Pluto, the spacecraft’s instruments are being repurposed. //
New Horizons is now nearly twice as far from the Sun as Pluto, the outer planets are receding fast, and interstellar space is illuminated by the vast swath of the Milky Way ahead. But the spacecraft’s research is far from over. Its instruments are all functioning and responsive, and the New Horizons team has been working hard, pushing the spacecraft’s capabilities to carry out new tasks. //
In 2021, his team photographed a dark patch of sky and digitally removed all known light sources in the Universe. What remained—the estimated COB—is roughly twice as bright as expected. “Our test field was far from the Milky Way, bright stars, dust clouds—anything that would wash out the fragile darkness of the Universe, yet that mysterious glow is still there. It’s like being in an empty house out in the countryside, on a clear moonless night, with all the lights turned off, and finding it’s not completely dark,” said Lauer.
Since the analemma is considered one of the most difficult and demanding astronomical phenomena to image, I immediately set out on such a marathon during the summer of 2001 by pursuing a complete set of analemmas from 08:00:00 to 17:00:00 UT+2 (hourly intervals) as well as the special case of the perfectly vertical analemma on the meridian (12:28:16 UT+2). For complete details and analysis concerning the analemma on the southern meridian, the interested reader is referred to my article in Coelum Astronomia (Vol 60: 71-74, Feb/2003). The project's successful completion provided various firsts including the first analemma ever imaged in Greece; the first image ever of the perfectly vertical analemma; the first analemma(s) ever imaged during a single calendar year; the first to ever image more than one analemma; and the first to ever capture two analemmas on a single piece of 35mm film.
If you took a picture of the Sun at the same time each day, would it remain in the same position? The answer is no, and the shape traced out by the Sun over the course of a year is called an analemma. The Sun's apparent shift is caused by the Earth's motion around the Sun when combined with the tilt of the Earth's rotation axis. The Sun will appear at its highest point of the analemma during summer and at its lowest during winter. Today, the Winter Solstice day in Earth's northern hemisphere, the Sun is at the bottom of the analemma. Analemmas created from different latitudes would appear at least slightly different, as well as analemmas created at a different time each day. This particular analemma was built up by 46 separate Sun photographs taken during 2003 in Athens, Greece. Pictured in the foreground of this composite image are pillars called the Porch of Maidens, part of the ancient Erechtheum which was completed in 407 BC.
The animated motion of the analemma sun below was constructed from the original film negative containing the 46 single exposures. Its purpose is to illustrate the wandering motion of the sun during twelve months and whose net motion is described by the analemma curve or "figure eight". The bottom apex point represents winter solstice whereas the first solar disk to the immediate upper-left is the start of January and where we observe the gradual and steady increase in the sun's altitude from day-to-day. This increase continues into February and March and, by mid-April, we have reached the cross-over point between the two loops. The sun continues its steady rise across local skies but is now on the right portion of the upper loop and which peaks at the apex point of the upper loop on summer solstice. It is at this point that the sun will now start another gradual and steady pace but this time with declining altitude and where, during July and August, it will traverse the left side of the upper loop. We reach the cross-over point once again but this time at the end of August with the sun now losing altitude at a greater pace while it is now on the right side of the lower loop and which will climax with the winter solstice and the apex point once again.
Incredible as it may sound, only seven times has someone ever managed to successfully image the solar analemma as a multi-exposure on a single piece of film. An analemma is basically the figure "8" loop that results when one observes the position of the sun at the same time during the day over the course of a year. As a result of the earth's tilt about its axis (23.5°) and its elliptical orbit about the sun, the location of the sun is not constant from day to day when observed at the same time on each day over a period of twelve months. Furthermore, this loop will be inclined at different angles depending on one's geographical latitude.
As suggested by the relatively few number of successfully completed analemmas (seven total including the pioneering photo in 1979), the imaging of the sun over local skies during the course of twelve months is considered one of the most difficult and demanding astronomical phenomena to image. The analemma presented below is one of TEN analemmas completed during a marathon started in 2001 in an attempt to document the complete range of analemmas from sunrise to sunset (see here). It is further unique as it represents the fifth of eight analemmas ever imaged during a single calendar year and also the fifth analemma ever imaged in Greece.
Note: For an animation involving the analemma at 13:00:00 UT+2 and which beautifully documents the actual motion of the sun during twelve consecutive months when observed at precisely 13:00:00 UT+2, please see the example here.
Note: As noted elsewhere, more men have walked on the moon than have successfully photographed the analemma (see S&T, Dec/2003: 73).
Here at Flightradar24 we’re big fans of anything in the sky and that includes astronomical photography, but we were pleasantly surprised when we came across Andrew McCarthy’s photo of the 30 August Super Blue Sturgeon moon. Taken in Arizona southeast of Phoenix, the photo captures not only the moon, but an aircraft passing in front of the moon.