Discovered nearly a year ago, Comet Leonard is on its last tour of Earths neighborhood, lighting up the night sky for audiences this holiday. Comet Leonard– the brightest and most expected comet of the year– was found by Gregory Leonard, a senior research professional at the University of Arizonas Lunar and Planetary Laboratory, in January 2021. The comet was found, somewhat unintentionally, utilizing the Catalina Sky Surveys 1.5-meter (60-inch) telescope at the Mount Lemmon Infrared Observatory, located in the Santa Catalina Mountains in Arizona.The comet, formally understood as C/2021 A1, has actually given that been making its way to the inner solar system, passing near Earth on Dec. 12, Venus on Dec. 17, and now en path towards the sun, anticipated to reach perihelion on Jan. 3. Heres our field glasses and telescopes guide to see Comet Leonard, and if youre hoping to photograph the comet take a look at best video cameras for astrophotography and finest lenses for astrophotography guides.Related: Comet Leonard will light up the sky this month– heres how to see itHowever, this showing is expected to be the comets last– a minimum of in our solar system (it wont be near Earth once again for another 80,000 years). Space.com took a seat with Leonard to talk about how the comet was first spotted and what skywatchers can anticipate to see in the night sky during the last leg of the comets solar system tour. This interview has been modified for length and clarity.Space.com How did you discover Comet C/2021 A1? Gregory Leonard: I am an astronomer with the Catalina Sky Survey, a NASA-funded project based out of the University of Arizona, and we are directed to discover and track near-Earth asteroids– the kind of asteroids whose orbits can bring them near the Earth and potentially impact the Earth. I found Comet C/2021 A1 Leonard– also known to the world as Comet Leonard– on the morning of Jan. 3, 2021. It was a serendipitous, or incidental, discovery in among our basic study fields, trying to find near-Earth asteroids. We do sometimes stumble into unknown comets, whichs precisely what Comet Leonard was. I saw the things not as a point or star-like things like most asteroids would appear to us, but this one had the telltale fuzzy coma that comets have– and the coma is that thin, rare environment that forms around the nucleus of a comet when it gets close enough to the sun to thrill and sublimate, or boil off, the ices that the comet is made from. In addition to seeing that thin coma, or that fuzziness around the comet, I also discovered a little stubby tail, and that obviously is another telltale indication that its likely a comet. Astronomer Gregory Leonard at the Catalina Sky Survey observing station. (Image credit: Catalina Sky Survey) Space.com: You discussed that the comets discovery was serendipitous or unforeseen. Can you discuss why?Leonard: This comet was my 10th comet discovery, and because that time Ive discovered 3 more, so there are really 13 Comet Leonards out there. Now, I dont call these comets. They immediately presume the name of the innovator, which in all these cases was me over the last 6 years. They are unexpected [because] we are trying to find near-Earth asteroids and its just on celebration that we stumble into what appears to be a comet, and then we report those to the Minor Planet Center at Harvard, Massachusetts, which is the clearinghouse for all asteroid and comet observations. What was unforeseen about this comet was its orbit. Unlike a lot of other comets that are discovered throughout the year, this comet is on an orbit that brings it reasonably close to the sun and the Earth– close enough for it to possibly be seen from the backyard by casual observers. Space.com: What is the comets origin and composition?Leonard: Its origin is likely from a remote sphere of comets called the Oort Cloud, which is a vast tank of millions, or possibly billions, of comets. The Oort Cloud is really far [from the sun] Its at least 5,000 astronomical systems– an astronomical system is the sun-Earth range– and might go out as far as 100,000 huge systems. This comet likely came from the inner Oort Cloud, 3,700 astronomical units away and its what we call a long-period comet. The comet has been inbound, on this leg, for the last 40,000 years. [Nevertheless] , if we trace that back, its actually been on an 80,000-year orbit. The last time it wouldve come [into] the inner planetary system would have been 80,000 years back. What its made of is still to be figured out. There are most likely telescopes around the world that have actually been taking a look at the spectra from the comet, and I think well see some documents and research study come out in 2022 talking a bit more about precisely what [the comet] is made from. Im sure well see some of the usual comet suspects, and that would be water ice, carbon dioxide, carbon monoxide, some ammonia and possibly some other unique substances. Whats intriguing, too, is that when I found the comet, it was 450 million miles away– about the range that Jupiter orbits the sun– and the reality that I spotted a tail is intriguing [because] water ice will not sublimate at that distance, in that cold region of area. So its some other substance that would likely have actually been boiling away and sublimating, possibly a carbon dioxide or carbon monoxide gas. I believe this comet will be observed after its perihelion– its close passage by the sun on Jan. 3– as far out as it can be observed by telescopes, and were going to get a much better concept about what its composed of. Space.com: You said you found the comet on Jan. 3, and now its closest method is slated for Jan. 3, 2022. Is that just a coincidence? Leonard: It is. Jan. 3 of this year, 2021, was the real discovery. It was discovered exactly one year before perihelion– that is strictly coincidental, but I like coincidence. Comet Leonard shines intense in this image from the European Space Agencys Near-Earth Object Coordination Centre utilizing the Calar Alto Schmidt telescope in Spain. It was developed by stacking 90 5-second direct exposure pictures of the comet taken on Dec. 7, 2021 on top of each other. (Image credit: ESA/NEOCC) Space.com: Since its discovery, what have we learned from this comet, either about comets in basic or about the early planetary system? Leonard: Once we understand better the specific composition of this comet, it will give us some ideas and ideally patch in some holes of understanding about the conditions that existed at the time of the formation of our planetary system. Comets are really, extremely beautiful and they bring this details with them. These were basically unchanged, unaffected, primitive bodies remaining from the development of all the worlds. This is why they are actually exciting for astronomers and scientists to scrutinize to better understand where we came from. Comets, in addition to the near-Earth asteroids that my project searches for, impacted the Earth billions of years back and likely brought some quantity of water, adding to our oceans and freshwater resources. When we look at comets, were actually looking at pieces of our own history; our own development of our climate, and, in truth, perhaps even some of the constituents of what we ourselves are made of. Space.com: How did Comet Leonard make its way into the inner planetary system? Leonard: The comets that reside in the Oort Cloud are held in a gravitational balance in between the feeble yank of the suns gravity and the entire gravitational yank of our [Galaxy] galaxy. With the tiniest little bit of gravitational nudging, or disruption in the galaxy, these comets can either sort of fall out of the Oort Cloud or they can start their long journey inwards to our sun– and thats exactly what took place when it comes to this comet. Thats how many long-period comets get their beginning: Theyre gravitationally pushed or irritated and the sun wins the fight. So they begin cascading inwards toward the sun, taking thousands and countless years to do so. In this case, we have to say hey there and bye-bye to Comet Leonard. This is its final passage [in our planetary system] It has an escape velocity, moving at 44 miles per 2nd, or 70 kilometers per 2nd, which is enough for it to be flung out from our solar system permanently. Much like it takes rockets a particular minimal velocity to leave the gravity of Earth, the solar system also has an escape velocity. Comet Leonard has that velocity, so once it passes close to the sun on Jan. 3, it will, from that point forward, be moving away and will leave our solar system and travel countless years maybe to stumble into some other outstanding system a very long time from now. Space.com: The comets latest planetary flyby was at Venus on Dec. 17. What effect do you believe the comet had on the planet?Leonard: That stays to be seen. One thing that we will be looking for is the potential for Venus to travel through the dust stream left by the comet. The comet is going to pass by Venuss orbit and after that Venus is going to travel through that area. Its possible then that Venus might experience a meteor shower from the dust particles left in the wake of Comet Leonards death. Its possible with the geometry of Earth that could be visible with telescopes from Earth. [Likewise] the Japanese Space Agency, JAXA, has an orbiting spacecraft around Venus today. Its called Akatsuki … and its on a Venus climate mapping objective. However, there might be a chance for some of the sensors on Akatsuki to look for possible meteors entering the upper Venusian atmosphere. Oh, to be an observer on the night side of Venus, as Comet Leonard travelled by, it would have been breathtaking to see. It passed about 2.6 million miles [4.2 million kilometers] from Venus on Dec. 17 and Dec. 18, which seems like a long method– and for us in the world, it is– nevertheless, thats actually just a cosmic whisker. It just missed out on almost clobbering Venus by a couple of days. … [The comets] Earth flyby was about 22 or 23 million miles [35 or 37 million kilometers], so it was 10 times closer to Venus in its flyby there. Space.com: What can we expect as the comet heads now towards the sun? Leonard: Well, I believe the only thing thats constant about comets is their utter unpredictability. A smart comet hunter and originator when said comets are like cats: both have tails and both do specifically what they desire– and that holds true. Its most likely that [Comet Leonard] is going to dim. Whichs not so much due to the fact that its getting near the sun, [Since] the Earth is now truly declining. Both things are declining from one another. Normally, when a comet approaches the sun, we tend to see a lightening up. , if the Earth wasnt moving away from [ the comet], we would likely see simply that. Were most likely to see it dim just since were moving away. Nevertheless, theres always a chance that as it nudges closer to the sun, that there could be some increased activity, possibly some outgassing or some jetting– some outburst that occurs that will brighten the comets look from Earth.Space.com: And what causes those outbursts?Leonard: As a comet approaches the sun, youll get the ices sort of violently sublimating and boiling away. If theres a pocket of product thats suddenly released, which launches pressure, that might be enough to sort of pull the comet apart– they are very fragile things. Comets have a really low density. The density of water is one gram per cubic centimeter, and the density of a comet is a third of that … so these are very fragile items and any forces at all, be they associated or gravitational to the volatile release from these ices blowing away, suffices to expose more product, and have that material boil away. This could be one cause for a brightening– for an outburst of the comet. Another recent result … is a phenomenon called forward scattering. The comet was extremely close in angle to the sun and the sunlight shining through, or essentially backlighting, all the dust in the tail has been understood to allow comets to brighten considerably by one, two and even 3 magnitudes. So, it can momentarily brighten for 12 or 24 hours.Space.com: So we wont see the comet once again because of its escape velocity. Where do you believe its going to go? Leonard: I havent seen any forecasts as to which instructions its flying off into our galaxy. Itll be enjoyable to see what potential star system it could bump into lots of, numerous years from now. Suffice it to say that this is the last check out [to our planetary system] However there still is a chance for folks that truly wish to see it. What I would suggest is to escape the intense lights of your town or city, be armed with a pair of binoculars– the bigger, the much better– or a small telescope, if you have one. Its actually beyond naked-eye presence at this point. … And, if you dont see it, feel in ones bones that weve had a terrific cosmic visitor for this winter season season.Follow Samantha Mathewson @Sam_Ashley13. Follow us on Twitter @Spacedotcom and on Facebook.
Heres our field glasses and telescopes guide to see Comet Leonard, and if youre hoping to photograph the comet check out best cams for astrophotography and best lenses for astrophotography guides.Related: Comet Leonard will light up the sky this month– heres how to see itHowever, this proving is anticipated to be the comets last– at least in our solar system (it will not be near Earth again for another 80,000 years). I saw the object not as a point or star-like object like a lot of asteroids would appear to us, but this one had the obvious fuzzy coma that comets have– and the coma is that thin, tenuous atmosphere that forms around the nucleus of a comet when it gets close enough to the sun to sublimate and thrill, or boil off, the ices that the comet is made of. Can you describe why?Leonard: This comet was my 10th comet discovery, and because that time Ive found three more, so there are in fact 13 Comet Leonards out there. Space.com: What is the comets origin and composition?Leonard: Its origin is likely from a distant sphere of comets called the Oort Cloud, which is a huge reservoir of millions, or maybe billions, of comets. With the slightest bit of gravitational nudging, or disruption in the galaxy, these comets can either sort of fall out of the Oort Cloud or they can start their long journey inwards to our sun– and thats exactly what occurred in the case of this comet.
