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Can you see the comet named SWAN? The answer is, with luck, maybe. If we wish to see Comet SWAN, we’ll want some clear nights coming in the next week or so. Here’s a chart with hand-drawn positions of C/2020 F8 (SWAN) over the next month. June 2 would be our best opportunity as the comet will be highest above the horizon and near the star Capella, which will help in finding it. Getting the timing right will be challenging, between twilight fading enough for the faint object to be seen and spotting it before the comet sets! You’ll still need good binoculars to see this one and a clear view to the northwestern horizon. Place your order now for clear skies to be delivered the night of June 2 … DO IT NOW! Supplies are limited.

Chart of Comet SWAN's path May 22 to June 22

Comet C/2020 F8 (SWAN) will make a low arc across the northwestern horizon over the coming month. Here’s a hand-drawn plot. Credit: SkySafari/J. Guilford

Comet SWAN has been a Southern Hemisphere object until just recently. I’ve heard some people here, up north, have caught glimpses of the comet already though it’s so low to the horizon that, even with clear skies, by the time the sky gets dark in the northwest, the comet is setting! And as the days and weeks pass, the progression of the starry background takes everything closer to the horizon — or you could think of the horizon rising, when looking at a chart. Add to that the fact that days are getting longer, sunset and twilight later, the comet lower… ugh! It seems everything’s a race! By mid-June Comet SWAN will be lost in bright twilight.

Comet C/2020 F8 (SWAN) was officially discovered March 25 of this year. It will make its closest approach to the Sun (perihelion) on May 27 when it will be 64 million kilometers from our star. Officially classified C/2020 F8 (SWAN) the new comet was first spotted by Australian amateur astronomer Michael Mattiazzo on April 11 using data from the Solar Wind ANisotropies (SWAN) instrument aboard the NASA/ESA Solar and Heliospheric Observatory (SOHO) recorded on March 25.

If you spot SWAN, please let us know! Good luck!

Postscript….

Comets, being temperamental beasts, don’t always act as we’d expect or hope. Most of the time comets gain brightness as they draw nearer the sun; Comet SWAN has been dimming! I’d seen earlier mentions but this Sky & Telescope article just came out today… HUMBUG!

Observations made with the European Southern Observatory’s Very Large Telescope (ESO’s VLT) have revealed the telltale signs of a star system being born. Credit: ESO/Boccaletti et al.

Observations made with the European Southern Observatory’s Very Large Telescope (ESO’s VLT) have revealed the telltale signs of a star system being born. Credit: ESO/Boccaletti et al.

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May 20 — “Thousands of exoplanets have been identified so far, but little is known about how they form,” says Anthony Boccaletti who led the study from the Observatoire de Paris, PSL University, France. Astronomers know planets are born in dusty discs surrounding young stars, like AB Aurigae, as cold gas and dust clump together. The new observations with ESO’s VLT, published in Astronomy & Astrophysics, provide crucial clues to help scientists better understand this process.
“We need to observe very young systems to really capture the moment when planets form,” says Boccaletti. But until now astronomers had been unable to take sufficiently sharp and deep images of these young discs to find the ‘twist’ that marks the spot where a baby planet may be coming to existence.

The new images feature a stunning spiral of dust and gas around AB Aurigae, located 520 light-years away from Earth in the constellation of Auriga (The Charioteer). Spirals of this type signal the presence of baby planets, which ‘kick’ the gas, creating “disturbances in the disc in the form of a wave, somewhat like the wake of a boat on a lake,” explains Emmanuel Di Folco of the Astrophysics Laboratory of Bordeaux (LAB), France, who also participated in the study. As the planet rotates around the central star, this wave gets shaped into a spiral arm. The very bright yellow ‘twist’ region close to the center of the new AB Aurigae image, which lies at about the same distance from the star as Neptune from the Sun, is one of these disturbance sites where the team believe a planet is being made.

 

The images of the AB Aurigae system showing the disc around it. The image on the right is a zoomed-in version of the area indicated by a red square on the image on the left. It shows the inner region of the disc, including the very-bright-yellow ‘twist’ (circled in white) that scientists believe marks the spot where a planet is forming. This twist lies at about the same distance from the AB Aurigae star as Neptune from the Sun. The blue circle represents the size of the orbit of Neptune. The images were obtained with the SPHERE instrument on ESO’s Very Large Telescope in polarized light. Credit: ESO/Boccaletti et al.

The images of the AB Aurigae system showing the disc around it. The image on the right is a zoomed-in version of the area indicated by a red square on the image on the left. It shows the inner region of the disc, including the very-bright-yellow ‘twist’ (circled in white) that scientists believe marks the spot where a planet is forming. This twist lies at about the same distance from the AB Aurigae star as Neptune from the Sun. The blue circle represents the size of the orbit of Neptune. The images were obtained with the SPHERE instrument on ESO’s Very Large Telescope in polarized light. Credit: ESO/Boccaletti et al.

 

Observations of the AB Aurigae system made a few years ago with the Atacama Large Millimeter/submillimeter Array (ALMA), in which ESO is a partner, provided the first hints of ongoing planet formation around the star. In the ALMA images, scientists spotted two spiral arms of gas close to the star, lying within the disc’s inner region. Then, in 2019 and early 2020, Boccaletti and a team of astronomers from France, Taiwan, the US and Belgium set out to capture a clearer picture by turning the SPHERE instrument on ESO’s VLT in Chile toward the star. The SPHERE images are the deepest images of the AB Aurigae system obtained to date.

With SPHERE’s powerful imaging system, astronomers could see the fainter light from small dust grains and emissions coming from the inner disc. They confirmed the presence of the spiral arms first detected by ALMA and also spotted another remarkable feature, a ‘twist’, that points to the presence of ongoing planet formation in the disc. “The twist is expected from some theoretical models of planet formation,” says co-author Anne Dutrey, also at LAB. “It corresponds to the connection of two spirals  — one winding inwards of the planet’s orbit, the other expanding outwards — which join at the planet location. They allow gas and dust from the disc to accrete onto the forming planet and make it grow.”

ESO is constructing the 39-meter Extremely Large Telescope, which will draw on the cutting-edge work of ALMA and SPHERE to study extrasolar worlds. As Boccaletti explains, this powerful telescope will allow astronomers to get even more detailed views of planets in the making. “We should be able to see directly and more precisely how the dynamics of the gas contributes to the formation of planets,” he concludes.

Photo: Comet 17P/Holmes by James Guilford

Comet Redux. Reprocessing old images shot through the Stephens Observatory telescope shows Comet 17P/Holmes as it appeared October 28, 2007. The two dots are bright stars shining through the comet’s coma. Photo by James Guilford.

Back in 2007 astronomers were excited by a comet known as 17P/Holmes. What was so exciting was that the seemingly ordinary visitor from distant parts of the Solar System suddenly put on a great show. In October, the usually dim 17P/Holmes changed from an unremarkable telescopic object to become visible to the unaided eye, appearing as a yellow “star” in constellation Perseus. It was briefly the largest object in the Solar System. The outburst was believed to be similar to one that took place in 1892 making it visible to amateur astronomer Edwin Holmes, credited with its discovery on November 6 of that year. The reason for the sudden brightening or outbursts remains unknown.

I used my little Canon Rebel XT digital camera attached to the vintage Cooley Telescope at Stephens and attempted to capture images of the comet. The effort and the camera were pretty primitive compared with what we can do now but I got some images and they were the best I could manage at the time. Comet 17P/Holmes faded from visibility over the next several weeks. The somewhat odd appearance of the comet — no classic head and tail — is the result of our perspective: looking straight down its tail instead of from the side.

Recently I viewed a television show about comets and the strange behavior of 17P/Holmes was discussed. That program reminded me of the 2007 apparition and to look at my old images. There wasn’t much image data to work with but I reprocessed what I have and produced a new image a bit better than my first try; that image, shot through our old telescope, appears above.

The “P” in the comet’s designation stands for periodic, meaning after a period of time 17P will return to loop, once again, around Sun. In March 2014 (a seven-year period) the loop was made without an outburst. The next close approach to our Sun, perihelion, will take place on February 19, 2021. Will we be treated to another show?

— James Guilford

This artist’s impression shows the orbits of the objects in the HR 6819 triple system. This system is made up of an inner binary with one star (orbit in blue) and a newly discovered black hole (orbit in red), as well as a third star in a wider orbit (also in blue). Image Credit: ESO/L. Calçada

May 6 — A team of astronomers from the European Southern Observatory (ESO) and other institutes has discovered a black hole lying just 1,000 light-years from Earth. The black hole is closer to our Solar System than any other found to date and forms part of a triple system that can be seen with the naked eye. The team found evidence for the invisible object by tracking its two companion stars using the MPG/ESO 2.2-meter telescope at ESO’s La Silla Observatory in Chile. They say this system could just be the tip of the iceberg, as many more similar black holes could be found in the future.

“We were totally surprised when we realized that this is the first stellar system with a black hole that can be seen with the unaided eye,” says Petr Hadrava, Emeritus Scientist at the Academy of Sciences of the Czech Republic in Prague and co-author of the research. Located in the constellation of Telescopium, the system is so close to us that its stars can be viewed from the southern hemisphere on a dark, clear night without binoculars or a telescope. “This system contains the nearest black hole to Earth that we know of,” says ESO scientist Thomas Rivinius, who led the study published today in Astronomy & Astrophysics.

The team originally observed the system, called HR 6819, as part of a study of double-star systems. However, as they analyzed their observations, they were stunned when they revealed a third, previously undiscovered body in HR 6819: a black hole. The observations with the FEROS spectrograph on the MPG/ESO 2.2-meter telescope at La Silla showed that one of the two visible stars orbits an unseen object every 40 days, while the second star is at a large distance from this inner pair.

Dietrich Baade, Emeritus Astronomer at ESO in Garching and co-author of the study, says: “The observations needed to determine the period of 40 days had to be spread over several months. This was only possible thanks to ESO’s pioneering service-observing scheme under which observations are made by ESO staff on behalf of the scientists needing them.”

The hidden black hole in HR 6819 is one of the very first stellar-mass black holes found that do not interact violently with their environment and, therefore, appear truly black. But the team could spot its presence and calculate its mass by studying the orbit of the star in the inner pair. “An invisible object with a mass at least four times that of the Sun can only be a black hole,” concludes Rivinius, who is based in Chile.

 

This chart shows the location of the HR 6819 triple system, which includes the closest black hole to Earth, in the constellation of Telescopium. This map shows most of the stars visible to the unaided eye under good conditions and the system itself is marked with a red circle. While the black hole is invisible, the two stars in HR 6819 can be viewed from the southern hemisphere on a dark, clear night without binoculars or a telescope. Credit: ESO, IAU and Sky & Telescope

Astronomers have spotted only a couple of dozen black holes in our galaxy to date, nearly all of which strongly interact with their environment and make their presence known by releasing powerful X-rays in this interaction. But scientists estimate that, over the Milky Way’s lifetime, many more stars collapsed into black holes as they ended their lives. The discovery of a silent, invisible black hole in HR 6819 provides clues about where the many hidden black holes in the Milky Way might be. “There must be hundreds of millions of black holes out there, but we know about only very few. Knowing what to look for should put us in a better position to find them,” says Rivinius. Baade adds that finding a black hole in a triple system so close by indicates that we are seeing just “the tip of an exciting iceberg.”

Already, astronomers believe their discovery could shine some light on a second system. “We realized that another system, called LB-1, may also be such a triple, though we’d need more observations to say for sure,” says Marianne Heida, a postdoctoral fellow at ESO and co-author of the paper. “LB-1 is a bit further away from Earth but still pretty close in astronomical terms, so that means that probably many more of these systems exist. By finding and studying them we can learn a lot about the formation and evolution of those rare stars that begin their lives with more than about 8 times the mass of the Sun and end them in a supernova explosion that leaves behind a black hole.”

The discoveries of these triple systems with an inner pair and a distant star could also provide clues about the violent cosmic mergers that release gravitational waves powerful enough to be detected on Earth. Some astronomers believe that the mergers can happen in systems with a similar configuration to HR 6819 or LB-1, but where the inner pair is made up of two black holes or of a black hole and a neutron star. The distant outer object can gravitationally impact the inner pair in such a way that it triggers a merger and the release of gravitational waves. Although HR 6819 and LB-1 have only one black hole and no neutron stars, these systems could help scientists understand how stellar collisions can happen in triple star systems.

This image is one of the most photogenic examples of the many turbulent stellar nurseries the NASA/ESA Hubble Space Telescope has observed during its 30-year lifetime. The portrait features the giant nebula NGC 2014 and its neighbor NGC 2020 which together form part of a vast star-forming region in the Large Magellanic Cloud, a satellite galaxy of the Milky Way, approximately 163,000 light-years away.

The space inside Stephens Memorial Observatory’s dome has seen throngs of people over the years. Anyone who has visited on a busy Public Night knows it doesn’t take very many people to make a crowd around the big telescope. So to help protect public health with the novel coronavirus on the loose our Public Nights are cancelled, almost certainly for the remainder of 2020.

In place of public gatherings, we plan to produce a series of non-technical short video programs on various astronomy-related topics. The first program will be a look at several telescopes and how they work. Announcement of programs will be made via this website and Twitter.

Here’s a link to a video of observatory director James Guilford talking about the situation:

If you have suggestions for program topics, please write us using the Contact Us tab at the top of this page.

COVID-19 coronavirus - Image Credit: CDC I don’t need to tell you the sort of impact the spread of the novel coronavirus has had on plans for, well, just about everything this spring. Around now is when we at Stephens Memorial Observatory would be scheduling and opening to the public for monthly stargazing.

As we noted in a recent post here, a small observatory dome is no place to collect a group of people — a group of any size — when there is a pandemic disease circulating. If you’ve been to one of our Open Nights, you know it gets crowded and loud with not very many people present!

So early on we independently decided to postpone our public openings.

The novel coronavirus is “out there” and circulating. It is foolhardy to believe that after two weeks or so it will simply go away. With no vaccine available, the only true preventative is isolation. So that’s what we’re doing.

Remember this when you think about whether widespread closures are actually needed: The virus that causes COVID-19 appears to spread about as easily as the common cold. But this disease can be much more severe — sometimes deadly. A deadly disease that can be caught and spread as easily as a cold! That’s the reason for current shutdowns of bars, restaurants, and other businesses that bring people together. Think about that, please, as you go about your daily living.

I believe relative isolation will be advised for the general public for some months to come. I enjoy our public nights together under the dome but I don’t want anyone, myself included, to become ill because of our little gatherings. So there’s a very good chance Stephens will not open to the public any time this year.

In the meantime, I’m putting together technologies that will allow us to share either live or recorded live views of astronomical objects from a local telescope. We may also do some video presentations about the observatory and its telescope. I’ll keep you informed about future developments along those lines.

I’ll close here by thanking you for your interest in what we do, and thanking those who are repeat visitors to our humble observatory. Please help stop the spread of the COVID-19 virus and stay well. We’re all in this together and it will take sensible behavior from all of us to get out.

 

Best wishes and stay healthy,

James Guilford, Director and Janitor
Stephens Memorial Observatory

For trustworthy information about the novel coronavirus, and COVID-19 disease, visit the Ohio Department of Health website: https://odh.ohio.gov/wps/portal/gov/odh/home

Well, it looks like we’ll not be opening our Public Nights season this month after all.

Outside of the usual concerns over wet and cloudy weather, and issues with our old building, now we have public health matters to take into consideration.

While the observatory is pretty much open to outside air when in use, people are quite close together under the dome — closer than public health experts recommend.

We’d rather everyone enjoy the night sky in good health and not have Stephens become a place where illness is spread; so we will watch and wait for resolution of the pandemic COVID-19 disease. When gatherings again make sense, we’ll announce and commence our season of Public Nights.

Until then, we’ll point out opportunities for home stargazing when clear nights occur and most of those suggestions come via our Twitter feed. You don’t need to have a Twitter account to see what’s going on, simple visit:  https://twitter.com/StephensObs

Through this all, we’ll fall back on the wisdom of The Hitchhiker’s Guide to the Galaxy upon which is written in large, friendly letters, “Don’t Panic”. No need to hoard toilet paper or bottled water. Just be smart about what you do to protect your health and the well-being of others. There’s plenty of good information available online if you choose wisely.

Here are a few good resources:

Ohio Department of Health

Ars Technica — Updated Daily

World Health Organization

 

Closed for the season

StephensAstro —  December 22, 2019 — Leave a comment
Photo: "Solstice Skies over Stephens" Photo by David Dreimiller.

“Solstice Skies over Stephens” Photo by David Dreimiller.

The winter months in Northeastern Ohio occasionally bring excellent conditions for astronomy; the season also brings the risk of deep snow, ice, frigid temperatures, and plenty of clouds. For the aforementioned reasons and more, Stephens Memorial Observatory is closed for the season. We thank everyone who attended our Open Night offerings in 2019 and hope to see you again in the new year, possibly in March. Until then, stay safe and warm, and keep looking up! Unless you’re under a bird. Then you might want to rethink.

Photo: The Orion Nebula by James Guilford, 2012

The Orion Nebula, Messier 42, as it may appear to viewers through small telescopes. Photo by James Guilford, 2012.

UPDATE: Over the course of the event 29 visitors enjoyed exquisite views of the Orion Nebula. Excellent seeing conditions allowed the nebular cloud to fill and extend beyond the telescope’s field of view at 104X magnification; possibly the finest view of that astronomical object that we have enjoyed. Also viewed was the red supergiant star, Betelgeuse, which is at the left shoulder of the constellation’s mythic figure. Betelgeuse has been the topic of discussion lately because the variable star has dimmed noticeably from its more typical brilliance.

Stephens Memorial Observatory of Hiram College will host a special Public Night Saturday, December 21, from 9:00 to 11:00 p.m. The Great Orion Nebula will be the featured object on a night billed as a “holiday gift.” The observatory is usually closed for the winter but organizers wished to offer views of the nebula this year. Clear skies will be especially important for this event.

Cloudy skies at the scheduled starting time cancel the event in which case, the observatory will not open. No reservations are required and there is no admission fee for observatory public nights.

The Observatory is located on Wakefield Road (Rt. 82) less than a quarter of a mile west of Route 700 in Hiram. There is no parking at the Observatory. Visitors may park on permissible side streets near the Post Office, a short distance east of the observatory.

Updates on programming are available via the Observatory’s Twitter feed: @StephensObs and on this website.