Sadly, there will be no Open Nights conducted at Stephens Memorial Observatory until further notice. As we write this, the only recommended means of preventing spread of the coronavirus disease 2019 (COVID-19) is to maintain at least six feet of distance between each other. Inviting the public to share the crowded space beneath the observatory’s ~16-foot dome would not be wise in view of the risk. We do not expect to conduct any Open Night sessions this year. Until we meet again, please watch this website for other news and follow us on Twitter. Thank you for your interest!
An international team of astronomers today announced the discovery of a rare molecule — phosphine — in the clouds of Venus. On Earth, this gas is only made industrially or by microbes that thrive in oxygen-free environments. Astronomers have speculated for decades that high clouds on Venus could offer a home for microbes — floating free of the scorching surface but needing to tolerate very high acidity. The detection of phosphine could point to such extra-terrestrial “aerial” life. Confirming the presence of life, however, will require much more work.
“When we got the first hints of phosphine in Venus’s spectrum, it was a shock!”, says team leader Jane Greaves of Cardiff University in the UK, who first spotted signs of phosphine in observations from the James Clerk Maxwell Telescope (JCMT), operated by the East Asian Observatory, in Hawaiʻi. Confirming their discovery required using 45 antennas of the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, a more sensitive telescope in which the European Southern Observatory (ESO) is a partner. Both facilities observed Venus at a wavelength of about 1 millimeter, much longer than the human eye can see — only telescopes at high altitude can detect it effectively.
The international team, which includes researchers from the UK, US and Japan, estimates that phosphine exists in Venus’s clouds at a small concentration, only about twenty molecules in every billion. Following their observations, they ran calculations to see whether these amounts could come from natural non-biological processes on the planet. Some ideas included sunlight, minerals blown upwards from the surface, volcanoes, or lightning, but none of these could make anywhere near enough of it. These non-biological sources were found to make at most one ten thousandth of the amount of phosphine that the telescopes saw.
To create the observed quantity of phosphine (which consists of hydrogen and phosphorus) on Venus, terrestrial organisms would only need to work at about 10% of their maximum productivity, according to the team. Earth bacteria are known to make phosphine: they take up phosphate from minerals or biological material, add hydrogen, and ultimately expel phosphine. Any organisms on Venus will probably be very different to their Earth cousins, but they too could be the source of phosphine in the atmosphere.
While the discovery of phosphine in Venus’s clouds came as a surprise, the researchers are confident in their detection. “To our great relief, the conditions were good at ALMA for follow-up observations while Venus was at a suitable angle to Earth. Processing the data was tricky, though, as ALMA isn’t usually looking for very subtle effects in very bright objects like Venus,” says team member Anita Richards of the UK ALMA Regional Centre and the University of Manchester. “In the end, we found that both observatories had seen the same thing — faint absorption at the right wavelength to be phosphine gas, where the molecules are backlit by the warmer clouds below,” adds Greaves, who led the study published today in Nature Astronomy.
Another team member, Clara Sousa Silva of the Massachusetts Institute of Technology in the US, has investigated phosphine as a “biosignature” gas of non-oxygen-using life on planets around other stars, because normal chemistry makes so little of it. She comments: “Finding phosphine on Venus was an unexpected bonus! The discovery raises many questions, such as how any organisms could survive. On Earth, some microbes can cope with up to about 5% of acid in their environment — but the clouds of Venus are almost entirely made of acid.”
The team believes their discovery is significant because they can rule out many alternative ways to make phosphine, but they acknowledge that confirming the presence of “life” needs a lot more work. Although the high clouds of Venus have temperatures up to a pleasant 30 degrees Celsius, they are incredibly acidic — around 90% sulfuric acid — posing major issues for any microbes trying to survive there.
ESO astronomer and ALMA European Operations Manager Leonardo Testi, who did not participate in the new study, says: “The non-biological production of phosphine on Venus is excluded by our current understanding of phosphine chemistry in rocky planets’ atmospheres. Confirming the existence of life on Venus’s atmosphere would be a major breakthrough for astrobiology; thus, it is essential to follow-up on this exciting result with theoretical and observational studies to exclude the possibility that phosphine on rocky planets may also have a chemical origin different than on Earth.”
More observations of Venus and of rocky planets outside our Solar System, including with ESO’s forthcoming Extremely Large Telescope, may help gather clues on how phosphine can originate on them and contribute to the search for signs of life beyond Earth.
by James Guilford
Hey! That’s my fireball!!
I had stepped outdoors to check the sky (hoping to see at least one Perseid Meteor) and witnessed a fireball at 11:36 PM; it was captured by the NASA All-Sky Fireball Network camera system hosted by Hiram College. That was the first time I had spotted a meteor that was also captured by the automated camera. The “shooting star” is not very impressive in the picture but it was a beauty by eye, glowing brightly and leaving a long “smoke trail” as it traveled from south to north.
Below is a summary of the data the NASA system was able to derive from Hiram, Oberlin College, and Allegheny Observatory imagery. Rather than a Perseids meteor, it was classified as an Alpha Capricornids meteor — that shower peaked in late July.
If you are interested in NASA’s All-Sky Fireball Network, here’s a link to their website. Meteor data are updated daily with image captures and event summaries. Hiram’s is one of 17 all-sky cameras located in the continental U.S. https://fireballs.ndc.nasa.gov.
On August 13, 2013, Hiram College became the host for one of NASA’s All-Sky Camera Fireball Network stations, Oberlin College and Allegheny Observatory joining with us. The automated camera system watches the sky every night for exceptionally-bright meteors called fireballs.
James Guilford operates Stephens Memorial Observatory for the Physics Department of Hiram College.
It’s Perseids season!
The annual Perseid Meteor Shower peaks from August 11 to 13, the event many consider to be the best meteor shower of the year, thanks to frequent meteors streaking across the sky and comfortable nighttime temperatures. This year, skywatchers can expect to see between 50 and 75 meteors an hour under dark skies, or about one meteor every minute. The meteors are bits of material strewn across Earth’s path in space by Comet 109P/Swift-Tuttle. The bits of dust and grit glow brightly as they burn up while entering Earth’s atmosphere at about 37 miles per second.
This year, for those who venture out before midnight on the peak date(s), Earth’s Moon won’t interfere. Dedicated meteor spotters — those who observe in the wee hours between midnight and dawn — may curse as Moon rises and brightens the sky, making faint meteors harder to see. There is another problem, however, much closer to home: the weather.
The weather forecast calls for mostly cloudy skies Tuesday and Wednesday nights. Of course.
Do not abandon hope.
The nights preceding and following the shower’s peak see occasional meteors from the Perseid and Alpha Capricornid showers and include fireballs (very bright meteors) from both. When the sky’s clear, go out and enjoy the mild nights that may include “shooting stars.” After twilight fades, find a dark spot, spread out a blanket, or untangle that deck lounge chair, apply a little mosquito repellent and look up. As your eyes grow used to the dark you’ll see more and more stars, planets Jupiter and Saturn gracing the southern sky, and with decently dark sky, spy the soft clouds of our own Milky Way galaxy. You’ll probably see a satellite or two, too.
Resembling a butterfly with its symmetrical structure, beautiful colors, and intricate patterns, this striking bubble of gas — known as NGC 2899 — appears to float and flutter across the sky in this new picture from the European Southern Observatory’s Very Large Telescope (VLT). This object has never before been imaged in such striking detail, with even the faint outer edges of the planetary nebula glowing over the background stars.
NGC 2899’s vast swathes of gas extend up to a maximum of two light-years from its center, glowing brightly in front of the stars of the Milky Way as the gas reaches temperatures upwards of ten thousand degrees. The high temperatures are due to the large amount of radiation from the nebula’s parent star, which causes the hydrogen gas in the nebula to glow in a reddish halo around the oxygen gas, in blue.
This object, located between 3000 and 6500 light-years away in the Southern constellation of Vela (The Sails), has two central stars, which are believed to give it its nearly symmetric appearance. After one star reached the end of its life and cast off its outer layers, the other star now interferes with the flow of gas, forming the two-lobed shape seen here. Only about 10–20% of planetary nebulae  display this type of bipolar shape.
Astronomers were able to capture this highly detailed image of NGC 2899 using the FORS instrument installed on UT1 (Antu), one of the four 8.2-meter telescopes that make up ESO’s VLT in Chile. Standing for FOcal Reducer and low dispersion Spectrograph, this high-resolution instrument was one of the first to be installed on ESO’s VLT and is behind numerous beautiful images and discoveries from ESO. FORS has contributed to observations of light from a gravitational wave source, has researched the first known interstellar asteroid, and has been used to study in depth the physics behind the formation of complex planetary nebulae.
This image was created under the ESO Cosmic Gems program, an outreach initiative to produce images of interesting, intriguing or visually attractive objects using ESO telescopes, for the purposes of education and public outreach. The program makes use of telescope time that cannot be used for science observations. All data collected may also be suitable for scientific purposes, and are made available to astronomers through ESO’s science archive.
Comet C/2020 F3 (NEOWISE) was, for us in North America, a predawn object requiring exceptional dedication for observing. In the second week of July, the comet had moved enough in its orbit to become visible in the evening sky — from late twilight to about 11 p.m. Unfortunately, cloudy nights have been the rule lately so opportunities have been few.
On Wednesday night, July 15, the sky forecast was a bit shaky but it turned out the sky cleared enough to allow C/2020 F3 to be seen. I raced off to an observing site some 25 minutes away from home, popular with sunset watchers and, occasionally, comet spotters. Arriving at the site I found the place mobbed, the parking lot nearly full, by scores of would-be comet viewers. Unfortunately, the comet was pretty much at the low end of naked-eye visibility. Light pollution reduced contrast between comet and background sky to make the object nearly invisible — binoculars were needed. It’s likely most of those in attendance never saw the comet.
Entitled “Purity and Pollution,” this picture (a single exposure of 8 seconds) shows a pristine wonder of the night sky floating serenely amongst the stars, clouds glowing brightly below illuminated by artificial light pollution. If we were only more careful with our artificial light, we’d save plentiful energy (and money) and gain back our starry skies as a bonus!
C/2020 F3 (NEOWISE) will be gracing our night skies for the next week or so and I hope to have more than one opportunity to record the event before it is gone. The next apparition of this comet is expected in about 6,800 years.
The talk amongst stargazers this summer has been the apparition of C/2020 F3 NEOWISE in Northern Hemisphere skies. Previously one comet had caused excitement over its potential showing but it broke up as it approached the Sun. Another fizzled and faded from view. But C/2020 F3 survived its July 3 close approach to the sun (perihelion) and emerged bigger and brighter than expected.
The comet’s brightness is due to its large nucleus — the head of the comet — which is the source of frozen gas and dust that produces the visible tail or coma. “From its infrared signature, we can tell that [the nucleus] is about 5 kilometers across,” said Joseph Masiero, NEOWISE deputy principal investigator at NASA’s Jet Propulsion Laboratory.
C/2020 F3 was discovered in infrared images captured by NASA’s NEOWISE spacecraft in March 2020. The object was assigned the unromantic designation of C/2020 F3 with the spacecraft’s name as discoverer.
Falling in from the outer solar system, then diving perilously close to the Sun gave our comet a boost in speed and increased its orbital period from about 4,500 years to about 6,800 years — a long time to wait for its return.
Until recently C/2020 F3 put in its appearances only in the predawn hours, rising a little after 3:30 AM and fading into the brightening sky a bit past 5:00 AM. It was also rising to only about 10º above the horizon placing it, much of the time, in the realm of morning clouds, mists, haze, and general murk.
But it’s not over.
While at the time of this writing C/2020 F3 continues to be viewable in the wee hours before dawn in the northeastern sky, sinking lower with each morning, it is now also showing in the post-sunset twilight. It’s still only becoming visible around 14º to 10º above the north-northwestern horizon as it sinks toward the horizon following the Sun. The comet sets around 12:30 AM.
Evenings, for the next couple of weeks and possibly into August, go comet hunting! Depending upon whether the sky is clear of obstructions, clouds, and haze, skywatchers may be able to see the comet with unaided eye. Good binoculars will help in finding it and will give seekers a better view. The comet will be very low to the horizon so an elevated location will aid in viewing. Use binoculars to look west and then past northwest in the deepening twilight, scanning slowly and just above the horizon. The comet will appear as a vertical streak with a bright dot at the lower end, as in the picture at the top of this page. It may not be spectacular but how many comets does one see in their lifetime?
Our outbound visitor from outer space makes its closest pass by Earth on July 23 when it will be 103.7 million kilometers — about 64 million miles — away returning in roughly 7,000 years.
There was much ballyhoo surrounding the penumbral lunar eclipse that would take place the night of July 4 – 5, 2020. We joined in just to explain a little about what was going on and what might be expected. Penumbral lunar eclipses take place when the Moon passes through the thin outer shadow Earth casts out into space; they are often very subtle, slight, and in this case, nearly undetectable. Just witness the photo above that shows the Full Buck Moon about one-half hour before maximum eclipse and the Moon at maximum. Casual observers saw no change across the entire event and it’s hard for us to see the difference even in photos that can be made to emphasize features! So we apologize if you waited up to see what we called the “subtle” eclipse but, if you did, you saw a beautiful Full Moon!
Then there was the much-less-promoted Sunday night, July 5, conjunction of Earth’s Moon, with planets Jupiter and Saturn… a lovely sight! We went out to photograph it an hour after moonrise and spied a brilliant orange Moon lighting up the scattered clouds with Jupiter shining through and Saturn making a somewhat dimmer appearance. A conjunction is when two or more celestial objects appear close together in our skies — emphasis on appear since Moon, Jupiter, and Saturn are separated by hundreds of millions of miles. We were surprised to see, in the photo below, that even Jupiter’s four Galilean Moons can be seen. The stars and planets appear oblong or as short streaks due to Earth’s rotation and the length of the camera exposure.
Following Saturday night’s penumbral lunar eclipse, Earth’s Moon will get together with two planets in a lovely conjunction Sunday night, July 5. Any time from about 10:30 PM EDT and later, look to the Moon, big, bright and round just past its Full phase. Above and to the left and right of that bright orb will be two bright star-like objects. On Luna’s left is planet Saturn and above and just to the right floats brilliant Jupiter.
Both Saturn and Jupiter are approaching their opposition — the point in their orbits where each planet will be exactly opposite the Earth from our Sun. Opposition also places a planet about as close as it can be to us making it easier to see in detail, and brighter in our night skies.
Jupiter achieves opposition on July 14, while Saturn reaches its on July 20. The change in distance between Earth and the two gas giants is relatively slow giving casual observers plenty of time to enjoy the close-up view through their telescopes; a week or so before or after opposition really makes little difference.
Binoculars or a small telescope will allow users to view Jupiter as a bright dot with its four companion Galilean Moons. It’s helpful to have either a tripod mount or a way to brace binoculars when looking at Jupiter as it’s hard to hold steady enough for good viewing without!
Small telescopes with a bit more power will allow viewers to see the major cloud bands of Jupiter’s atmosphere and those same four moons. Make note of the position of those moons and take a look night-to-night or even after a couple of hours in the same night and you will see what Galileo observed: that those little star-like dots move!
Turn that telescope to Saturn and enjoy a look at the planet’s distinctive rings; they are well-positioned for viewing this month. If seeing conditions are good and with enough magnification, viewers can observe a dark line running inside the rings, a gap called the Cassini Division. It should also be possible to see the gap between the rings and the planetary body.
Both Jupiter and Saturn are bright enough that the waning Gibbous Moon shouldn’t interfere much with observing. Fear not, however, our Moon and those planets part company over ensuing nights providing a darker background. Jupiter and Saturn should be in a good position for observing any time after about 10:30 PM all month so you won’t have to stay up very late to enjoy the view.
We’re fortunate that the night of July 4 is expected to be clear, and not just for the traditional booms and flashes of celebratory fireworks. Our Moon is getting in on the act, albeit with a much more subtle display in the form of a penumbral eclipse. The eclipse will take place from 11:07 PM to 1:52 AM EDT with maximum eclipse at 12:31 AM July 5.
We say subtle because, unlike a total lunar eclipse, Earth’s Moon will not change to reddish/coppery colors. The Moon will instead become oddly shadowed for a Full Moon, as it enters the outer fringes of Earth’s shadow in space — the penumbra. Only the “top” portion of Luna will pass through the penumbra making this eclipse especially slight. Still, it’s worth a look and it won’t be at a particularly late hour. A deeper penumbral lunar eclipse will take place the night of November 30, 2020.
While it’s possible to view this eclipse with the unaided eye, binoculars will provide an enhanced view as would a small telescope.
And just in case there’s any confusion, lunar eclipses are perfectly safe to view and photograph — it’s moonlight — so nothing to worry about there.
If you shoot any photos or have impressions to share with us, you can do so via our Twitter — @StephensObs
NASA Eclipse Page available here: Penumbral Lunar Eclipse of July 4 – 5, 2020.