keep your distance

by Victor Davis

artist alteration

keep your distance. “at least the diameter of a saturn-mass black hole’s event horizon” – Artists alteration, 2020 – Ted Frimet, no copyright held.

assuming zero angular momentum and zero charge

I thought you might include in the newsletter, this social distancing advice for the astronomically inclined, which leaves the calculation as an exercise for the viewer.

Here are the relevant numbers:

Formula for the Schwartzschild radius of a black hole: R=2MG/c^2 (discounting charge and spin)

Gravitational constant (G): 6.67 X 10^-11 m^3/kg.s^2

Mass of Saturn: 5.68 X 10^26 kg

Have fun. My ZWO camera, which my wife ordered as a Christmas/Birthday gift for me, is finally due to arrive tomorrow! I figure that means dreary weather for the next month at least.

Your optimistic astro-buddy,

Victor

Posted in May 2020, Sidereal Times | Tagged , | Leave a comment

Vanity Cards

by Theodore R Frimet

That in my own humble opinion every Amateur Astronomer wearing a mask is a masked crusader for our mutual pursuit of life and liberty.

I’ve got nothing. I have been waiting to write that phrase for a few years now. Oft borrowed quotes from the media, steeds sometimes have to rise to the occasion. I too have to turn the page to the genius that is Chuck Lorre. “I’ve got nothing” appeared in one of his vaunted vanity cards.

I can’t seem to put the under age trace of the ministry of magic on it. Without a whiff, or a valid search engine (one that works), it is forever lost. My missing quote has become a tattered piece of laundry linen, flapping endlessly in Springs’ daily breeze.

No, I haven’t hunkered down in a battery of toilet paper. Yet, here I am, confessing my sins using intellectual confetti. Toilet paper, how-so-ever, could certainly make good confetti.

A shout out to the Mayor of New York: be sure to ban tossing unused toilet paper rolls onto the rank and file of those on the front lines! Once the touted parade on Broadway begins its ascent, marking the end of our recently endured pestilence, paper confetti would be best served, shredded then tossed lightly with a showering of gratitude and freshly shed tears.

Looking at the table before me, I vy Allegre (half read, my fellow amateur), a tome on molecular biology – untouched for months, and a few weeks worth of AAAS Science journals. No fodder here for the canon that is Sidereal Times. Wimper.

Off to my library then! Ok. The bookshelf in the living room should do. Social distancing is very important to both life and limb. I concede to what works. I hoof off a few, brew a hot coffee, and hunker down to…um…I’ve got nothing there, either.

K2, where are you, when the children need you the most?

Fritz, the destroyer of dobsonians, appears. He alights onto the table, and drops quickly to the ground. With a single bound, be leaps to the window. What is it, Fritz, old boy? What do you see?

I see nothing, Fritz replies. My hearing however is excellent. And of late, I am getting a little tired of your wimping about. What kind of amateur are you, anyway? Certainly not one that doesn’t spy the night sky and speak of his accomplishments!

Be wary your wordiness, humankind. Try to use your ears, as I do. Listen, learn and be aware of the difference between the truth and the contrivances of misdirection. The night sky is a record of truth. Pure and pristine, even the tidal forces surrounding the disk of a black hole can be dissected by science. Clouds be damned and use your imagination in lieu of your telescopic views.

Big Pussycat, aka Maybelle, sleeps on her low lying perch. Not being disturbed by my temporary insanity, she is blissfully unaware of the dob destroyers’ dominance over my cup of Joe. I take a sip. It is cold. How could that be? I just brewed it. “Twasinow”, says Fritz.

Enter K2.

K2 had not only fallen into a time well that lasted 10 or more time-space detents, she had knocked my coffee onto a time-loop. Hidden from my sight, K2 skirmished a slice of time. She bumped my coffee cup. The cup superimposed itself with the vibrations of K2’s temporal nexus.

It perplexes me that the physics of my coffee, in temporal isolation, would work out differently and become a cold cup of Joe. I sputter the drink back into its mug. Get up and brew another. Bad pussycat.

In Cheshire Cat style, K2 pops her head into my timeline. I am not amused. Taken off guard, I jump up. Fritz is puzzled as to the source of my anxiety. He too, runs from the room. Maybelle sleeps soundly. My coffee is ready.

For the past few weeks, off and on, I have been working away from home, doing a job that is considered essential. Each away-evening I give my brain the pre-sleep suggestion that I would like to solve faster-than-light travel all the while bending space-time to my will.

Due to the existential nature that is Freud, many poignant reveries revealed in deep sleep are compounded by the fractal nature of the dream. The deeper meaning, unlike Pascal, is lost upon my hippocampus. The best that has risen, not unlike the cream in my cup, is me traveling upon a road. Slipping to one side or the other, correcting the gait of my car, we encroach upon a tunnel. I enter it as I awake from slumber. And once again, I’ve got nothing. ‘Twasilater.

 

Posted in May 2020, Sidereal Times | Tagged , , | Leave a comment

Snippets

compiled by Arlene & David Kaplan

-BBC

Biggest cosmic mystery ‘step closer’ to solution
The nature of this quirk, which allowed matter to dominate the Universe at the expense of antimatter, remains a mystery. Now, results from an experiment in Japan could help researchers solve the puzzle – one of the biggest in science. It hinges on a difference in the way matter and antimatter particles behave.
The world that’s familiar to us – including all the everyday objects we can touch – is made up of matter. The fundamental building blocks of matter are sub-atomic particles, such as electrons, quarks and neutrinos…more

artists conception of a comet

-BBC

‘Alien comet’ visitor has weird composition
The interstellar comet 2I/Borisov was detected in our Solar System last year. This mysterious visitor from the depths of space has provided astronomers with an unprecedented opportunity to compare it to comets that formed around the Sun. New data suggests it contains large amounts of carbon monoxide – a possible clue to where it was “born”…more

-BBC

Hubble’s 30th anniversary image
Hubble’s 30th anniversary image has been turned into a 3D “spaceflight” experience.
Experts created this visualisation showing the Giant Red Nebula and its smaller blue neighbour, which lie in a satellite-galaxy of the Milky Way…more

Hubble Telescope

-BBC


Hubble looks back in time 12.6 billion years
Experts have created a spectacular visualisation of the “Hubble Ultra Deep Field” – one of the deepest optical images of the Universe ever taken. It was assembled for the 30th anniversary of the space telescope’s launch…more

Quasar black hole

-BBC


Event Horizon Telescope: Black hole produces twisting jet
Hubble’s 30th anniversary image has been turned into a 3D “spaceflight” experience. One year on from publishing the first ever image of a black hole, the team behind that historic breakthrough is back with a new picture.
This time we’re being shown the base of a colossal jet of excited gas, or plasma, screaming away from another black hole at near light-speed. The scene was actually in the “background” of the original target…more

Posted in May 2020, Sidereal Times | Tagged , | Leave a comment

From the Director

Rex

 

 

 

by Rex Parker, Phd director@princetonastronomy.org

Astronomy in the Time of Coronavirus
AAAP’s operations at both Peyton Hall on campus and the Observatory at Washington Crossing State Park are closed until the coronavirus crisis normalizes and group gatherings are once again allowed. We’re probably all feeling stress from the disruptions. I deeply hope that you and yours are staying healthy and making the best of it during this difficult period.

AAAP Officer Elections coming up
In order to conduct elections of officers in keeping with our constitution and by-laws, I have asked John Church to be nominations chair. He will report this month on the status of a slate. The elections will be conducted via e-mail or survey on-line since we cannot meet in person. I am in discussions now with the Board regarding process and will be communicating the election plan to members by May.

Starlight for Our Eyes
Science and the study and practice of astronomy can be a great theme to pursue while we are immobilized at home with social distancing in place. Of course, it would help a little if our local skies would clear up, our retinas need starlight. Unfortunately, most professional as well as amateur centers for astronomy are shuttered. The entire mountain top observatory cluster in Chile (Cerro Tololo) where I do remote astronomy is now shut down, like the rest of the planet. So the image below is from the last data we were able to get.

NGC 2736 (image below) is part of a large supernova remnant in the constellation Vela in the southern sky, 820 light years away – close by astronomical standards. It was first described by England’s Sir John Herschel in March 1835 during his 4 year period doing astronomy in South Africa. Sometimes called the Pencil Nebula, NGC 2736 is a glowing sheet of gases and particles ejected from the supernova event about 11,000 years ago. Today a pulsar sits at the center of the original star. The red regions in the image below are mainly ionized hydrogen and the blue ionized oxygen, gases ejected from the inner layers of the star when it exploded. According to David Malin, the section seen here is part of a roughly spherical shell outlining the expansion of the supernova explosion, but that connection is really only visible in X-ray telescope images. The connectivity in optical wavelengths is obscured by dust from the explosion. The exploding star is thought to have quickly reached a brightness over 200 times that of Venus. Our human ancestors and animals and birds alike would have been dazzled by the sudden appearance of a daystar in 9000 BC, much as we are amazed by its remnants in the deep sky today.

NGC 2736, supernova remnant in the constellation Vela in the southern sky. Astrophoto by Rex Parker with Star Shadows Remote Observatory at Cerro Tololo in Chile.

Posted in April 2020, Sidereal Times | Tagged , | Leave a comment

From the Program Chair

by Ira Polans, Program Chair

All monthly club meetings have been cancelled due to Princeton University closing its campus and the need to social distance. I have reached out to the speakers affected by the cancellation (March, April, and May) and all have agreed in principle to give their talks once things return to normal.

While we’re going through this difficult time please stay safe and healthy.

Posted in April 2020, Sidereal Times | Tagged , | Leave a comment

Observatory Public Nights Postponed. Our Skies Remain Open

by Dave Skitt, Observatory Chairperson

The State of New Jersey closed our public state park buildings. This is part of the COVID 19 virus response. AAAP delayed the opening of our observatory for Friday Night Public Observing for your safety. This delay will remain in effect until NJ lifts the group congregation restriction.

All is not lost; the skies will remain open. How you might ask? Through the marvel of telescope technology and the internet.

AAAP recently assembled “the outreach scope” from a pre-owned Orion ED 80 refractor and iOptron AZM Pro mount. We equipped it with a flip mirror and the clubs’ Starlight Xpress Ultrastar C camera.

Appearing in this months edition of Sidereal Times is, Novice EAA Imager Captures Rare, Unseen Astronomical Phenomenon. There I describe the pleasure to dabble with the scope and learn how to use it. Inspired by my church switching to online video services, I have now learned how to broadcast live streaming video from the Ultrastar camera to the internet.

I invite you to check out our club’s Twitter page (@Princetonastro). Our social media is your temporary observatory gateway. Using Twitter, we will observe together over the next several Friday nights. I will be live broadcasting night sky views from my home observatory, weather permitting.

Together we wait for the AAAP observatory to re-open. There, we can share the stellar photons at the eyepiece. For the meanwhile, I hope you will join me in this technological substitute.

Posted in April 2020, Sidereal Times | Tagged , | Leave a comment

Nominations for AAAP Officers for 2020-21

by John Church, Nominations Chair

Dear Members,

Director Rex Parker has kindly asked me to serve as Nominations Chair for our upcoming May election. I am therefore very pleased to report that all of our present officers have agreed to be nominated for another term. In my estimation they have all performed admirably in their respective posts, often above and beyond the call of duty.

The slate is as follows:

For Director: Rex Parker
For Assistant Director: Larry Kane
For Secretary: John Miller
For Treasurer: Michael Mitrano
For Program Chair: Ira Polans
For Observatory Chair: Dave Skitt
For Outreach Chair: Gene Allen

As always, additional nominations can be made by any member in good standing. However, because we will not be able to meet in Peyton Hall to actually conduct the election in May, arrangements are being made to accept any additional nominations and conduct the election electronically. Please stay tuned to Sidereal Times for further details.

In this difficult time we need to keep the club up and running to the best of our ability. It is unfortunate that we cannot presently meet in person, hear all those wonderful programs that Ira has been arranging, and share anecdotes and personal greetings, but this too shall pass. In the meantime, we are still able to stay in touch electronically. Thank goodness the Coronavirus has not infected our computers!

John Church
Nominations Chair

Posted in April 2020, Sidereal Times | Tagged , , , | Leave a comment

Freeman J. Dyson: A Personal Remembrance

by John Church

The Amateur Astronomers Association of Princeton joins the world in mourning the passing of renowned mathematical physicist and noted author Freeman J. Dyson on February 28 of this year at the age of 96.

Freeman, an Emeritus Professor at the Institute for Advanced Study in Princeton, was a great supporter of the role of amateurs in astronomy. A member of the AAAP for nearly 50 years, he helped us build our observatory in Washington Crossing State Park as well as giving the club many lectures in the Peyton Hall auditorium, which was always filled to capacity for such treats.

I first met Freeman in the early 1970’s after having summarized an article of his entitled “Energy in the Universe.” I remember telephoning him (with some trepidation) and asking if he would consider joining the AAAP. He responded that he would indeed be interested. This led to a friendship that lasted nearly half a century, of which more anon.

Here are some abridged selections from back issues of our newsletter Sidereal Times that mention Freeman’s long involvement with the club:

The Nov. 10, 1973 transit of Mercury was observed and timed from John Church’s driveway, using the club’s 6-inch refractor. Present were Freeman Dyson and Tullio Regge of the Institute for Advanced Study. A report was sent to Sky and Telescope, and the timings were published. With Freeman’s help, plans were proceeding to place a club observatory in a modified aluminum garage at the Institute that would be put on roll-off tracks. Member and civil engineer Karl Koehler prepared detailed drawings for the project. This proposal was not adopted due to finding that the Institute would have required construction to be performed by outside labor, which the AAAP could not have afforded.

AAAP member and Institute for Advanced Study Prof. Freeman Dyson was the speaker for the September 1986 meeting.

Prof. Freeman Dyson, long-time AAAP member who participated in the observatory construction in the late ‘70’s, presented a talk entitled “Hunting Comets and Planets” at the November 1990 meeting.

Prof. and AAAP member Freeman Dyson spoke to the AAAP on the subject of “Revolutions in Astronomy” at the December 1993 meeting.

AAAP held its 40th Anniversary Dinner at the Frist Center on the Princeton campus in November 2002. Freeman Dyson, one of the Washington Crossing observatory’s builders, spoke on “A New Way To Look For Life In Cold Places Far From The Sun.”

Our 50th Anniversary Dinner was held on the campus of the Institute in November 2012, at which Freeman also spoke.

On a personal note, my wife and I were invited to the Institute’s Sept. 2013 “Dreams of Earth and Sky” celebration of Freeman’s career. At the banquet on the final evening I gave a few remarks on Freeman’s contributions to our club, including the part he took in the building of our observatory in Washington Crossing State Park in 1977 and 1978. He was there at the site on many Saturdays. Here is a photo of him helping to dig the trench for the foundation:

Freeman J. Dyson digging foundation

photo by Richard Peery ©2020

On one fine Saturday afternoon, Freeman and I laid the fourth tier of cinder blocks in the east wall of the observatory. He helped with the project in many other ways as well.

I had the privilege of meeting privately with Freeman in his Institute office on many occasions when we discussed various topics in physics, astronomy, and cosmology. (Unfortunately, I haven’t kept written notes of our discussions.) On these occasions he would kindly host me for lunch in the Institute’s cafeteria. He very generously gave of his time to critique my draft of a personal memoir entitled From Eve and Morning that I issued privately in 2003. I have several of his books that he signed for me.

Freeman’s talents as a superbly clear and concise writer in multitudes of areas not necessarily related to physics are so well known that it would be superfluous for me to comment further here. As but one example, he served for many years as an invited contributor to the New York Review of Books. These wonderfully-written pieces engendered many replies, not always in agreement with his own views on subjects such as climate change and the role of enormous projects. He was a fan of small projects done inexpensively by individuals and small teams.

To conclude, here is a quotation from one of Freeman’s articles in the New York Review of Books on the subject of “Final Theories in Physics.” This is, I think, a good summary of his philosophy.

I find the idea of a Final Theory repugnant because it diminishes both the richness of nature and the richness of human destiny. I prefer to live in a universe full of inexhaustible mysteries, and to belong to a species destined for inexhaustible intellectual growth.

We in the Amateur Astronomers Association of Princeton will fondly remember Freeman and his many contributions to the welfare of our club as well as in so many other areas.

– John Church

Posted in April 2020, Sidereal Times | Tagged , | Leave a comment

Gene’s Tele Vue Baseball Cap

by Dave Skitt
Observatory Chairperson

Gene’s Tele Vue Baseball Cap

To keep the memory of Gene Ramsey alive, I wrote a short piece about Gene and his Tele Vue baseball cap. It was posted in Tele Vue’s February 2020 Blog.

Posted in April 2020, Sidereal Times | Tagged , , | Leave a comment

Novice EAA Imager Captures Rare, Unseen Astronomical Phenomenon

by Dave Skitt, Observatory Chairperson

If you’ve been reading my emails lately, you know that Dr. Rex Parker, PhD, and I conducted a Keyholder training session on Sunday, March 8, 2020.  We focused on the clubs’ expanding Electronically Assisted Astronomy (EAA) capabilities.  

As a novice EAA imager, I thought the session went very well.  All in attendance exclaimed how rapidly the new EAA technology was evolving and broadening the reach of what can be seen with relatively short exposures.  Despite the nearly full moon, the images of M42 with the ZWO camera on the C14 and the Ultrastar camera on the cOrion ADA, 80mm outreach scope were nearly identical.  The only difference were the exposure times:  5 seconds with the C14 versus 24 with the outreach scope.

After the session, I stayed behind to practice some more with the outreach scope/camera and iOptron AZM Pro mount. I decided to really test the limits and image some objects in the constellation between Virgo and Canes Virenatici.  

Home of globular cluster, M53, the Black Eye galaxy (M64), the Coma Pinwheel galaxy (M99) and the Needle galaxy (NGC 4565), the constellation Coma Viranices (“Viranices Hair”) presents some fine challenges for EAA.  I wanted to narrow down what camera settings would work best on this spread of objects.

I started my adventure on M53.  But not before I synced the mount on Denebola in Leo and tweaked my focus on nearby Cor Caroli with a N95 focus mask.  The AZMP mount got M53 dead on!  The Ultrastars’ stacked 20 second exposures revealed it to be a “rather vivid and round nebula of sars”, just as Johann Bode had described it when he discovered it in 1775.  Awesome!

Next up, M64.  Not nearly dead on but toggling the flip mirror helped me center the fuzzy oval in the eyepiece.  Flip back to the camera.   Wow!  Here, 30 second stacked exposures revealed M64s’ irregular shape, uneven brightness and cool texture.  The dark “Black Eye” dust feature was stunning.

Since it was getting late, I decided to skip “the Pins” (M99) and go straight to “the Needle”, NGC 4565.   This would be a good challenge to end the night.  

Now the AZMP’s slews are quiet.  Really quiet.  So much so that I wasn’t sure that it had moved far enough to hit the Needle.  Rushing in the cold, I typed in 14 days seconds in the exposure box and hit enter.  What appeared on the screen took my breath away.  I shivered.

Close up, the image looked like a comet. But when viewed six feet from the screen, it looked like a planetary nebula.  Had I not cleared the image cache before slewing?  Could it be both?  I took a screenshot and texted it to Tom Swords, a passionate comet hunter.  “That’s not a comet”, Tom replied.

I then texted the image to Dr. Parker along with the RA/DEC coordinates (16h 55m 33.86s/-41o 50’ 51.6”).  His extensive background in astro-imaging lead him to believe I had stumbled upon some novel astronomical phenomena.  He immediately called Dr. David Nyell at Central Management for Official Sightings and sent him the image and data.  

Twenty-four hours later, Dr. D. Nyell replied.  “We at CMOS can only state that the object observed at those coordinates is a presumptive positive sighting.  The data will be forwarded to the Copernicus Celestial Discovery Center via their Hotline.  Please refrain from additional observations until April 5th.  At such time we will reassess our position”.  

Early Tuesday morning, I received a frantic phone call from someone who identified herself as Vira Di’ Seaz.  She exclaimed “the C-CD-C has confirmed that you have caught the CO-VID-EAA-19 virus, aka, the CoronEAA virus.  Please self-quarantine yourself at the observatory for 14 days for further observation.”  

“Fourteen Days?  What do I do after 14 days?”, I blurted out.

After a short pause, Vira replied, “Well…, Corona Borealis will be higher in the sky by then.  You could poke around there with your telescope until this whole thing blows over…”!

April Fools.

P.S.:  The coordinates given above are for NGC 6231 located in Scorpius.  It is labeled in Stellarium planetarium software as the “False Comet Nebula”.

artists conception of surreal galaxy

COVID-19 (but not EAA) Free in 2020!


AAAP’s Outreach Telescope: Orion ED80 refractor complete with “N95 Focus Mask” and Starlight Xpress Ultrastar Color Camera on iOptron AZM Pro mount. Additional side-view photo of AAAP’s Outreach Telescope on the right.

Posted in April 2020, Sidereal Times | Tagged , | Leave a comment

At Home in A Dome

by William Murray

Since I’m stuck at home for the foreseeable future (as is everyone else in the world) I decided that astronomy is the best occupation for my time. Here are the results of some imaging I’ve been doing. The monochrome images are with an ATIK Infinity video camera on my Astro-Physics 130 mm Starfire GT refractor:

M1, The Crab Nebula

M1, The Crab Nebula

IC443, The Jellyfish Nebula

IC443, The Jellyfish Nebula

The open cluster M46 with the foreground planetary nebula NGC2438

The open cluster M46 with the foreground planetary nebula NGC2438

NGC2158, a distant open cluster near M35 (part of which is seen in the upper left corner)

NGC2158, a distant open cluster near M35 (part of which is seen in the upper left corner)

NGC2903, a bright non-Messier galaxy in Leo

NGC2903, a bright non-Messier galaxy in Leo

M95, a barred spiral galaxy in Leo

M95, a barred spiral galaxy in Leo

 

The last shot is a test shot with my Mallincam Universe video Imager. Still working on optimizing this camera but when I do it should give some great wide-field images.

M42

M42

Now if only the weather would cooperate …

-Bill Murray

 

 

Posted in April 2020, Sidereal Times | Tagged , , , , , , , , , , , , , , , , , | Leave a comment

AutoFiLX200

by Theodore R Frimet

shrimp gumbo

Tasty little morsel, if you’re not going Vegan. I have been off the reservation for quite a few months. I’d got a hankering for shrimp gumbo for my telescope. You know, the Meade LX200 GPS that I’ve invested time and money into? Yes, yes, I know. Don’t get you started. We ALL have time and money invested in our telescopes. Yet, this is one tasty little morsel.

I was watching one of our AAAP members, awhile ago. He tipped and paused his tablet, while his mount ushered to a new venue. I was so impressed. After a few years of pushing a dob, and an SCT about, I decided that my final destination would be wireless. Yummy.

Enter our Ukraine European ally, and provider of all good things for the Meade LX 200 GPS, astro-gadget.net. This wireless support offer was clearly everything that the chef could summon to the menu. It works flawlessly with my iPhone 6S running iOS 13.3.1, and Sky Safari Plus. Hurray!

The price was not hefty, and despite anticipating the shipment, our business partner, Alexander, was with me, every step of the way. Thank you for mailing the order!

Замовлення отримано сьогодні і працює у справному стані.
Сподіваюсь на чисте небо та приємні спостереження 🙂
Дякую за вашу працю, вашу інтелект та вашу доставку!

Saturday night, and everything is all right. A waning crescent moon took a nose dive at 4:41 EST. I set up during daylight, and readied for a few hours of viewing. There were going to be clouds in the forecast. So I ruled out a car trip to Jenny Jump, and settled into my backyard.

Mu Cep – Garnet Star, Beta Monocerotis, Messier 34 and Messier 93 all found with ease. 

The Garnet Star was one of my first, “push-to” experiences, while on an AAAP Star Party. I hopped, from star to star, using charts, and brut eye measurements. Tonight, the pedestrian in me parted ways. I jumped with joy, not having to wander the night sky. My efforts to make observations of the Garnet Star were easy peasee.

Beta Monocerotis was truly a wonder. At first blush this brightest star in Monceres appeared as a doublet. Pushing the magnification, with an Explore Scientific 11mm 82 degree series eyepiece, resolved this Beta as 3 stars, just as 8:40 PM started to set in.

My evening was capped off with a visit to M34, sporting an open cluster. To be sure, I managed a one off on M93, an open star cluster in Puppis.

My Autostar II paddle display appeared to be too bright. I attempted an adjustment. I am one-off from the latest firmware, so the inevitable problem ensued. Communication was lost to my scope. It drifted peacefully about the night sky.

Rest assured, I powered down, and was ready to Automatic-Align. Then clouds from the East crept in. Having had two hours of fine observation, I mused, “to shroud, or not to shroud – that is the question”. I decided on the former, and brought our Meade LX200 GPS home to roost in its JMI case.

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