Author: StephensAstro

Happy Birthday, Cooley!

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Photo: Vintage Observatory Telescope. Photo by James Guilford.
The Cooley Telescope at Stephens Memorial Observatory

On October 25, 120 years ago, Rev. Lathrop Cooley, on the occasion of his 80th birthday, presented a 9-inch Warner & Swasey telescope to Hiram College. He remarked, “This instrument is erected here so that you may climb the steep of heaven and walk among the stars.” The Cooley Telescope has resided in Hiram since its dedication, first at Teachout Library and Observatory then, following a building fire, at Stephens Memorial Observatory.

Dedicated at Hiram College in 1901, it is a fine and unique example of turn of the (20th) century astronomical telescope technology being complete as manufactured, including its functional weight-driven drive. As is customary, the telescope was named for the benefactor who provided it, Lathrop Cooley. See our History page for more about Mr. Cooley.

The telescope and its mount were made by the Warner and Swasey Company in Cleveland at their telescope factory located at Carnegie Avenue and East 55th Street. The outstanding optics were produced by the John Brashear Company, Pittsburgh. Over the years the Cooley Telescope has provided splendid views of Earth’s Moon, planets, nebulae, star clusters, comets, and even Sun, to many hundreds, perhaps thousands of visitors. Though the telescope remains operable, it is in need of mechanical overhaul and refurbishment.

We’re still observing restrictions meant to prevent the spread of COVID-19 but we hope it will not be very much longer before we can again share the wonders of the universe with visitors. After all, the Cooley Telescope is a gift that keeps on giving possibly for another century or so!

Dedication Plaque affixed to the Cooley Telescope
Dedication Plaque affixed to the Cooley Telescope

Our active Sun

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The Sun, showing several sunspots/active regions. This image was made at 3:43 PM EDT/7:43 PM UTC on September 10, 2021 using the photographer’s personal reflecting telescope with safe solar filter, and DSLR camera body. Credit: James Guilford

After a long period of quiet during our Sun’s fairly predictable 11-year activity cycle, things have been happening. What was a bright, clear disk has become speckled with sunspots of late. The increased activity brings with it the chance of Earth-directed coronal mass ejections, or CMEs, which result in solar storms when they collide with our home planet’s magnetic field. Auroras, or “northern lights” for us, are one potential result of solar storms. The less pleasant effects can include disruption of radio communications and satellite operation, all the way to electrical grid failures at the extreme!

Several recent CMEs have missed Earth but one is headed in our direction as this blog entry is being written. According to SpaceWeather.com, “{A} CME is on the way following an explosion in the magnetic canopy of sunspot AR2864 on Sept. 8th. NOAA analysts believe Earth could experience a glancing blow or near miss late on Sept. 11th.” Those favored with clear skies and a good view to the north may want to be on the lookout for aurora, but the odds aren’t favorable … this time!

Here are two photos of Sun, shot by Stephens’ Director James Guilford, at 3:43 PM EDT (7:43 PM UTC). The first image shows the full solar disk. Notice not only the dark sunspots but also the lighter-colored “splotches” of additional active solar regions, most visible near the edges of the disk.

The second image is cropped to show the major concentration of the day’s sunspots with their official numerical designations. Both images have been color tinted.

A tightly-cropped portion of the day’s full-disk image shows three sunspot groups: AR 2866, AR 2868, and AR 2869. Sunspots only appear to be dark because they are significantly “cooler” than the surrounding solar atmosphere; they are actually quite hot. Sun’s shining photosphere has a temperature of 5,800 degrees Kelvin while sunspots have temperatures of around 3,800ºK (6,380℉). Nearly all of the dark features seen here are larger than planet Earth. Credit: James Guilford

Centaurus A captured by the Dark Energy Camera

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The galaxy Centaurus A, which lies over 12 million light-years away in the direction of the southern-hemisphere constellation Centaurus (The Centaur), is the leading light of this striking image. This image provides a spectacular view of the luminous glow of stars and dark tendrils of dust that hide the bright center of the galaxy. This dust is the result of a past galactic collision, in which a giant elliptical galaxy merged with a smaller spiral galaxy. As well as large amounts of gas and dust, Centaurus A’s dust lane contains widespread star formation, as indicated by the red clouds of hydrogen and by the large numbers of faint blue stars visible at each end of the dust lane.

Credit: CTIO/NOIRLab/DOE/NSF/AURA

Astronomers make first clear detection of a moon-forming disc around an exoplanet

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This image, taken with the Atacama Large Millimeter/submillimeter Array (ALMA), in which ESO is a partner, shows wide (left) and close-up (right) views of the moon-forming disc surrounding PDS 70c, a young Jupiter-like planet nearly 400 light-years away. The close-up view shows PDS 70c and its circumplanetary disc center-front, with the larger circumstellar ring-like disc taking up most of the right-hand side of the image. The star PDS 70 is at the center of the wide-view image on the left. Two planets have been found in the system, PDS 70c and PDS 70b, the latter not being visible in this image. They have carved a cavity in the circumstellar disc as they gobbled up material from the disc itself, growing in size. In this process, PDS 70c acquired its own circumplanetary disc, which contributes to the growth of the planet and where moons can form. This circumplanetary disc is as large as the Sun-Earth distance and has enough mass to form up to three satellites the size of the Moon. Credit:ALMA (ESO/NAOJ/NRAO)/Benisty et al.

The Great Dimming of Betelgeuse explained in new research

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These images, taken with the SPHERE instrument on ESO’s Very Large Telescope, show the surface of the red supergiant star Betelgeuse during its unprecedented dimming, which happened in late 2019 and early 2020. The image on the far left, taken in January 2019, shows the star at its normal brightness, while the remaining images, from December 2019, January 2020 and March 2020, were all taken when the star’s brightness had noticeably dropped, especially in its southern region. The brightness returned to normal in April 2020.

June 16, 2021 — When Betelgeuse, a bright orange star in the constellation of Orion, became visibly darker in late 2019 and early 2020, the astronomy community was puzzled. A team of astronomers have now published new images of the star’s surface, taken using the European Southern Observatory’s Very Large Telescope (ESO’s VLT), that clearly show how its brightness changed. The new research reveals that the star was partially concealed by a cloud of dust, a discovery that solves the mystery of the “Great Dimming” of Betelgeuse.

Betelgeuse’s dip in brightness — a change noticeable even to the naked eye — led Miguel Montargès and his team to point ESO’s VLT towards the star in late 2019. An image from December 2019, when compared to an earlier image taken in January of the same year, showed that the stellar surface was significantly darker, especially in the southern region. But the astronomers weren’t sure why.

The team continued observing the star during its Great Dimming, capturing two other never-before-seen images in January 2020 and March 2020. By April 2020, the star had returned to its normal brightness.

“For once, we were seeing the appearance of a star changing in real time on a scale of weeks,” says Montargès, from the Observatoire de Paris, France, and KU Leuven, Belgium. The images now published are the only ones we have that show Betelgeuse’s surface changing in brightness over time.

In their new study, published today in Nature, the team revealed that the mysterious dimming was caused by a dusty veil shading the star, which in turn was the result of a drop in temperature on Betelgeuse’s stellar surface.

Betelgeuse’s surface regularly changes as giant bubbles of gas move, shrink and swell within the star. The team concludes that some time before the Great Dimming, the star ejected a large gas bubble that moved away from it. When a patch of the surface cooled down shortly after, that temperature decrease was enough for the gas to condense into solid dust.

“We have directly witnessed the formation of so-called stardust,” says Montargès, whose study provides evidence that dust formation can occur very quickly and close to a star’s surface. “The dust expelled from cool evolved stars, such as the ejection we’ve just witnessed, could go on to become the building blocks of terrestrial planets and life,” adds Emily Cannon, from KU Leuven, who was also involved in the study.

June 10 dawns with a partially eclipsed Sun

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Annular Eclipse of the Sun. Image Attribution: Smrgeog, CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons

An annular eclipse of the sun will take place June 10 and it will be underway at sunrise. Unfortunately, even with clear skies we will not see the “ring of fire” that is the namesake look of this type of eclipse. In fact, no place in the United States will see the complete circle, or annulus, of Sun around Moon. So don’t feel left out.

In our area, sunrise will be at 5:55 AM (EDT) with the eclipse already at its maximum for us. The eclipse ends at 6:35 AM as Moon completes its passage across Sun.

A total eclipse of the sun takes place when Earth’s Moon, at normal orbital distances, covers the solar disk completely and blocks all but the glowing corona from view. An annular eclipse takes place when Moon is at higher points in its orbit when it passes between Earth and Sun, too distant and small to form a perfect cover, allowing a brilliant ring of our star to shine.

What we may see at dawn and diminishing thereafter, is a partial solar eclipse — looking a bit like the chomping character from the classic PAC-MAN video game. Much of the solar disk will be visible but the curved edge of Moon will take a bite out of one side.

How can you watch the eclipse? With great care!

Partial Eclipse of the Sun, August 21, 2017 — this image rotated to resemble what viewers might see at dawn, June 10, 2021. Photo by James Guilford

How can you watch the eclipse? With great care! At no time during our partial solar eclipse will it be safe to watch the event without vision protection. If you have eclipse glasses from a recent solar eclipse, those should be just fine — just make sure there are no pinholes or other damage to the plastic film “lenses”! You can check for damage by holding the eclipse viewer at arm’s length and looking at a bright lightbulb. If you see any dots of light through the viewer film, throw those glasses out!

Do NOT look at the sun through sunglasses, even multiple sets of sunglasses, or photo negatives, Compact Discs, or anything other than certified eclipse viewing equipment! Pinhole and other projection techniques can be used safely since the viewer is looking at a projection and not the sun itself. Five Ways to View the Solar Eclipse

“The Sun can be viewed safely with the naked eye only during the few brief seconds or minutes of a total solar eclipse. Partial eclipses, annular eclipses, and the partial phases of total eclipses are never safe to watch without taking special precautions. Even when 99% of the Sun’s surface is obscured during the partial phases of a total eclipse, the remaining photospheric crescent is intensely bright and cannot be viewed safely without eye protection [Chou, 1981; Marsh, 1982]. Do not attempt to observe the partial or annular phases of any eclipse with the naked eye. Failure to use appropriate filtration may result in permanent eye damage or blindness!” — NASA: Eye Safety During Solar Eclipses

Total lunar eclipse? Uh, not this time.

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This map shows where the May 26, 2021 lunar eclipse is visible. Contours mark the edge of the region where the eclipse will be visible at the times when the Moon enters or leaves the umbra (the part of the Earth’s shadow where the Sun is completely hidden) and penumbra (the part where the Sun is only partially blocked). Credit: NASA’s Scientific Visualization Studio.

They say timing is everything and, with eclipses, that is certainly true. Unfortunately, timing will not be in our favor for viewing the Wednesday, May 26 total lunar eclipse. Earth’s Moon will be dipping very close to the horizon as morning twilight brightens hiding the most colorful portion of the event — totality — when Moon turns shades of copper and red. The subtle penumbral eclipse as Moon enters Earth’s outer shadow and will likely be even harder to see than usual. The partial phase of the eclipse begins as Moon enters the dark inner portion of the shadow cone and is easily spotted under other circumstances. Even the partial eclipse begins so late with Moon so close to the horizon that only a lucky few Ohioans will see any part of it.

Penumbral Eclipse beginsMay 26 at 4:47 a.m.
Partial Eclipse beginsMay 26 at 5:45 a.m.
Total Eclipse beginsMay 26 at 7:11 a.m.
Maximum EclipseMay 26 at 7:18 a.m.
Eclipse Timings — Eastern Daylight Time — Northeastern Ohio

The good news? Lunar eclipses can occur only at the time of a Full Moon and this event features a perigee Moon — our natural satellite at a particularly low portion of its orbit around Earth — appearing just a bit bigger and brighter than average. “Low”, in this case means 221,880 miles out. So, if skies allow, get out and enjoy the big, brilliant Full Moon tonight — it’s a natural wonder in its own right.

Visibility of the total phase in the contiguous U.S., at 11:11 UTC. Totality can be seen everywhere in the Pacific and Mountain time zones, along with Texas, Oklahoma, western Kansas, Hawaii and Alaska.

Still want to watch the eclipse, even though we can’t see it from here? Just do an online search for live eclipse viewing opportunities or tune in to your favorite morning TV news show; they’ll be broadcasting from the West Coast or Hawaii where the eclipse can be properly seen!

Don’t despair, dear moonwatcher! Come this November 19, in the wee hours of the morning, we will be in an excellent position to see a nearly total lunar eclipse from our own backyards! More on that at a later time!

Happy “birthday” Hubble Space Telescope! We get the gift.

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In celebration of the 31st anniversary of the launch of the NASA/ESA Hubble Space Telescope, astronomers aimed the celebrated observatory at one of the brightest stars seen in our galaxy to capture its beauty. The giant star featured in this latest Hubble Space Telescope anniversary image is waging a tug-of-war between gravity and radiation to avoid self-destruction. The star, called AG Carinae, is surrounded by an expanding shell of gas and dust. The nebula is about five light-years wide, which equals the distance from here to our nearest star, Alpha Centauri. Credit: NASA, ESA and STScI

The giant star featured in this latest Hubble Space Telescope anniversary image is waging a tug-of-war between gravity and radiation to avoid self-destruction. The star, called AG Carinae, is surrounded by an expanding shell of gas and dust — a nebula — that is shaped by the powerful winds of the star. The nebula is about five light-years wide, which equals the distance from here to our nearest star (beyond our own Sun), Alpha Centauri.

The huge structure was created from one or more giant eruptions several thousand years ago. The star’s outer layers were blown into space, the expelled material amounting to roughly 10 times the mass of our Sun. These outbursts are typical in the life of a rare breed of star called a Luminous Blue Variable (LBV), a brief unstable phase in the short life of an ultra-bright, glamorous star that lives fast and dies young. These stars are among the most massive and brightest stars known. They live for only a few million years, compared to the roughly 10-billion-year lifetime of our own Sun. AG Carinae is a few million years old and resides 20 000 light-years away inside our Milky Way galaxy. The star’s expected lifetime is between 5 million and 6 million years.

LBVs have a dual personality. They appear to spend years in  semi-quiescent bliss and then they erupt in a petulant outburst, during which their luminosity increases — sometimes by several orders of magnitude. These behemoths are stars in the extreme, far different from normal stars like our Sun. In fact AG Carinae is estimated to be up to 70 times more massive than our Sun and shines with the blinding brilliance of 1 million suns.

First flight on another planet takes a little Ingenuity

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Ingenuity-In-Flight
Shown in this screen grab from a video, the small “Ingenuity” rotorcraft made history, hovering above Jezero Crater, demonstrating that powered, controlled flight on another planet is possible. The video including this image was captured by the Perseverance rover parked nearby. Image Credit: NASA/JPL
April 19, 2021 — NASA’s Ingenuity Mars Helicopter became the first aircraft in history to make a powered, controlled flight on another planet. The Ingenuity team at the agency’s Jet Propulsion Laboratory in Southern California confirmed the flight succeeded after receiving data from the helicopter via NASA’s Perseverance Mars rover at 6:46 a.m. EDT (3:46 a.m. PDT).
ingenuity-1st-flight-cropped
A tight crop from a video frame showing the Ingenuity Mars Helicopter during its historic first flight on Mars. The video including this image was captured by the Perseverance rover parked nearby. Image Credit: NASA/JPL
The solar-powered helicopter first became airborne at 3:34 a.m. EDT (12:34 a.m. PDT) – 12:33 Local Mean Solar Time (Mars time) – a time the Ingenuity team determined would have optimal energy and flight conditions. Altimeter data indicate Ingenuity climbed to its prescribed maximum altitude of 10 feet (3 meters) and maintained a stable hover for 30 seconds. It then descended, touching back down on the surface of Mars after logging a total of 39.1 seconds of flight.

For more on the Ingenuity Mars Helicopter technology demonstration, click here!

Ingenuity Mars helicopter to take flight soon

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NASA’s Ingenuity Mars helicopter is seen in a close-up taken by Mastcam-Z, a pair of zoomable cameras aboard the Perseverance rover. This image was taken on April 5, 2021, the 45th Martian day, or sol, of the mission.
Credits: NASA/JPL-Caltech/ASU

UPDATE: Based on data from the Ingenuity Mars helicopter that arrived late Friday night, NASA has chosen to reschedule the Ingenuity Mars Helicopter’s first experimental flight to no earlier than April 14. CLICK HERE for the full story.

A livestream confirming Ingenuity’s first flight is targeted to begin around 3:30 a.m. EDT Monday, April 12, on NASA Television, the NASA app, and the agency’s website, and will livestream on multiple agency social media platforms, including the JPL YouTube and Facebook channels. When it happens it will be the first flight of an aircraft operated on another planet.