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Issue 158 April 2019

A NEWSLETTER OF THE ROCKEFELLER UNIVERSITY COMMUNITY Natural Selections Interviews Rockefeller’s Viviana Risca, Principal Investiga- tor of the Laboratory of Genome Architecture and Dynamics A l ic e G a dau

At the age of fourteen, Viviana Risca spent her summer break unlike most teenag- ers. Every morning, she took the train from Long Island to work in Dr. Daniel Eich- inger’s parasitology laboratory at New York University. Despite the cabinet full of dead worms in formaldehyde she had to pass ev- ery morning, this first exposure to biological research was highly influential in propelling her into a lifetime of research. Since then she has been excited about using molecular techniques to understand the processes that occur in cells. NATURAL SELECTIONS NATURAL

Viviana has now joined the Rockefell- | er community as one of the two new tenure- track assistant professors hired in 2018. Af- ter completing her Ph.D. in Biophysics at the University of California, Berkeley, she con-

tinued her scientific career as a postdoctoral ALICE GADAU scholar at Stanford University with Profes- sor William J. Greenleaf. Viviana is interest- Viviana Risca ed in the biophysical rules that contribute to the dynamics and stability of the genome. In they express different sets of genes that give therapies and diagnostics. addition, she wants to understand how the rise to their unique identities. As a postdoc at Stanford, I worked three-dimensional genome architecture can My lab seeks to understand how on exploring how the landscape of enzyme- regulate DNA-based processes. three-dimensional chromatin structure con- accessible chromatin can give us insights trols the ways in which various proteins, into the regulatory networks that control Alice Gadau: What is the central ques- including those involved in transcription, gene expression in several cell types, includ- tion you are trying to address in your lab, access their binding sites on DNA in order ing a cancer model, using a popular method and how is this an expansion from your past to perform their biological functions. One called ATAC-seq. I also did a lot of technol- work? of the driving hypotheses of our work is that ogy development, which resulted in RICC- Viviana Risca: The three-dimensional chromatin structure acts as an integrator of seq, a method for mapping chromatin fiber structure of the genome is controlled by its many molecular inputs to modulate access structure at high resolution, and ChAR-seq, association with a variety of proteins, to- to DNA. I am particularly interested in how a method for mapping contacts between gether making up a DNA-protein complex chromatin modifications, inter-molecular RNA and DNA genome-wide. In my own we call chromatin. Through the efforts of interactions, and polymer effects give rise lab, we will continue to use and develop large-scale sequencing projects, we now to specialized parts of the cell’s nucleus that these technologies, applying them toward know much of the linear sequence of bases stably repress transcription and help main- the goal of understanding the basic biophys- that make up the human genome, but we tain cell identity and normal cell function. ical and molecular mechanisms responsible are still far from fully understanding the Both chromatin structure and the processes for stable transcriptional repression and mechanisms that control how and when the that shape it are often perturbed in cancer, overall control of access to genomic DNA. information encoded in DNA sequence is as well as during aging, and I hope that our read out by transcription. A skin cell and a work on these fundamental processes will muscle cell contain the same genome, but provide useful leads toward better cancer CONTINUED TO P. 2 - 1 CONTINUED FROM P. 1 - tentially phase-separated domains like the nucleolus. How this long-range organization AG: How does three-dimensional ge- relates to short-range chromatin folding is Editorial Board nome architecture contribute to DNA regula- also an area that my lab plans to explore. tory processes? Sarah Baker Editor-in-Chief, VR: Since the 1920s when Emil Heitz AG: What is RICC-seq and how can it Managing Editor, Webmaster coined the terms euchromatin and hetero- accurately examine short range DNA con- chromatin, we have known that the cell nu- tacts? Jim Keller cleus is divided between regions of high and VR: RICC-seq stands for ionizing Ra- Editor-at-Large low chromatin density. Since then, we have diation-Induced Correlated Cleavage. In the Megan Elizabeth Kelley learned that organization of chromatin is far 1990s, it was shown that the pattern of DNA Associate Editor, Communication from random—it is in fact organized at mul- damage induced by X-rays or gamma-rays tiple length scales. on a cell’s genome is shaped by the way the Emma Garst Editorial Assistant At short length scales, every 150- DNA is folded into chromatin. RICC-seq 200 bp of eukaryotic genomes is wrapped takes advantage of this convenient property Nicole Infarinato around roughly 10 nm-wide histone com- of chromatin. We irradiate cells with X-rays Copy Editor, Distribution plexes called nucleosomes. Regions of DNA or gamma rays, carefully extract the short Melissa Jarmel that are depleted of nucleosomes tend to be pieces of resulting single-stranded DNA, Copy Editor, Website Traffic hyper-accessible to exogenous enzymes we and then sequence those pieces. Their ends use to probe them, and we interpret these tell us about the pattern of DNA damage Donna Tallent regions to be also accessible to endogenous and consequently, about the way the DNA Copy Editor proteins like transcription factors, chroma- was folded in the original cell. This method Nan Pang tin remodelers and polymerases. Indeed, works well for mapping high-resolution Guadalupe Astorga many of these proteins seem to localize to DNA-DNA contacts on the order of less Designers nucleosome-depleted DNA. We also know than 10 nm and less than a thousand base that some histone modifications, like lysine pairs, making it complementary to other selections.rockefeller.edu acetylation, is associated with low-density, three-dimensional structure mapping meth- [email protected] euchromatic regions of the genome that ods like Hi-C, which work better for con- tend to be more accessible to protein bind- tacts spanning thousands of kilobases. ing. The high-density, heterochromatic parts with chromatin engineers to develop pertur- of the genome are less well understood, AG: What makes RICC-seq novel from bations that will help us dissect causal and from a structural standpoint, and many other sequencing techniques? functional relationships between molecular labs, including my own, are currently try- VR: RICC-seq has two unique ad- factors and chromatin structure. ing to decipher the mechanisms that drive vantages. First, it can be performed on liv- the exclusion of transcriptional machinery ing cells that are not fixed or permeabilized. AG: Are there other hobbies you have from these silent genomic regions. Candi- Therefore, we can probe chromatin struc- that incorporate science? date mechanisms that have been proposed ture in its native state. Second, it uses hy- VR: I’ve long loved incorporating skills include occlusion of binding sites by DNA droxyl radicals generated by radiation as its that I pick up in the lab into my other hob- buried in compacted chromatin, chemical probe. The radiation can penetrate all areas bies. When I learned microscopy and optics, exclusion by phase-separated liquid do- of the nucleus, no matter how dense, and the I also took up photography in my spare time, mains, and simple volume exclusion from radicals are smaller than water and can eas- because the basic concepts are the same. I high density regions. ily diffuse. Therefore, we can get data from love art in general and see a lot of parallels We also know that there is functional not only the low-density euchromatin in the between the lives of scientists and artists. We communication between genomic regions at nucleus, but also from highly compacted, are both seeking fundamental truths, and much longer length scales spanning tens of dense heterochromatin. both need to continually find ways to nur- thousands and sometimes hundreds of thou- ture our creativity. I also love to cook. I often sands of kilobases. Enhancer elements in the AG: What other tools are you incorpo- use it to relax because it uses many of the genome, which are acetylated, hyperacces- rating in your lab to understand genome ar- same skills as biochemistry or molecular bi- sible, and bound by transcription factors chitecture? ology, but you can usually determine failure when active, somehow must communicate VR: RICC-seq is not a single-cell or success more rapidly than at the bench, with gene promoter regions because they method and requires quite a bit of input ma- and it is also easier to share your successes regulate these promoters. This is thought terial, so we will be combining it with lower- with your friends. to happen via DNA looping interactions in input methods like single cell or bulk ATAC- Lastly, I love science outreach and three dimensions, but the exact nature and seq and RNA-seq, as well new cutting-edge communications, but I would not call those dynamics of these contacts are an active technologies as they emerge. We will also hobbies. I think all of us as scientists have area of research and not yet understood. be complementing this work with protein a responsibility to share our work with the Lastly, we also know that the cell nucleus is binding measurements like ChIP-seq or public that, after all, supports our work divided up into regions with different func- CUT&RUN, and microscopy that can tell through taxes and donations, to advocate for tional profiles, through associations with us about the long-range organization of the the societal benefits of basic research, and to the nuclear lamina or self-association of po- nucleus. Lastly, we will also be collaborating equitably educate the next generation. n 2 With a Schmear A i l e e n M a r s h a l l

New York City is known for many things—culture, nightlife, and food, to name a few. We already know about the widely recognized style of New York pizza and hot dogs. But did you know that the city is known for having the most authentic ba- gels? You can now get one anywhere, from a mass produced bagel in your local grocery store (generally not recommended) to many bakeries, delis, and restaurants around town, however they weren’t always so widely available. Where did bagels come from? Various ancient cultures had some form of a bagel-like bread. There are Egyp- tian hieroglyphics that depict everyday people with round shaped bread with a hole unemployedeater.com Courtesy of Photo in the middle. The design makes for even Assorted bagels cooking and allows for easy transport, since many can be carried on a stick or a string. The bagel as we know it probably evolved in Eastern Europe, particularly Poland, in the Middle Ages. The earliest mention of a bagel in writing was from 1610 in the “Communi- ty Regulations” of Krakow. There is a legend that they were invented in 1683 in honor of the Polish king Jan Sobieski for saving Aus- tria from Turkish invaders, but the earlier mention casts doubt on the story. Bagels came to this country with East- ern European immigrants in the late nine- teenth century. By 1900, there were seventy bagel bakeries on the Lower East Side. In Photo Courtesy of Stu Spivack Courtesy Stu of Photo 1907 the International Beigel Bakers Union Bagels with lox was founded, which had the effect of limit- ing production mostly to this city. As these They should have absolutely no resemblance texture. Montreal’s bagels have dough con- immigrants assimilated and moved across to white Wonder Bread. Some say that New taining malt and sugar but no salt. Honey the country, so too did the popularity of and York City water gives bagels a better taste. is added to the boiling water for a sweeter demand for bagels. Murray Lender, a Polish According to the Smithsonian, the ratio of taste. In London, bagels are smaller with a immigrant, opened a wholesale bagel bak- calcium to magnesium in our water binds courser texture and more air bubbles. Since ery in New Haven, Connecticut in 1927, one with the gluten in the dough to give the ba- there is no legal regulation, many companies of the few outside New York at the time. A gels the accurate degree of chewiness. produce what they call “bagels” that are very turning point came in 1956, when the Lend- Bagels come in different flavors in- far from the real thing. ers bought a freezer. They soon realized they cluding onion, sesame seed, poppy seed, Here in New York City, there are sev- could ship frozen bagels to distant retailers cinnamon raisin, pumpernickel, rye, whole eral famous bagel places as well as many without them going stale. Today bagels are wheat, and egg. An “everything bagel” has smaller neighborhood establishments. The common in supermarkets, but Lenders’ ba- some combination of these ingredients, hav- most familiar are Zabar’s, Russ and Daugh- gels are the only mass produced bagels that ing evolved from bakeries trying to use up ters, the Second Avenue Deli, and Ess-a-Ba- retain authenticity. all the dough they had left over. Bagels can gel. Another well-known store, H&H Bagels, By tradition, bagels are made by let- be eaten as is or toasted, and usually topped is characteristically New York in that it was ting the shaped wheat-based dough sit for with either butter, cream cheese (a schmear), founded by a Puerto Rican family. The clos- twelve hours at a cool temperature, around jelly, lox, tomatoes, onions, capers, or some est source to our university is Bagelworks, 40˚ to 50˚ F. Then they are boiled for about a combination of these. Around Saint Pat- on First Avenue at 66th Street. So enjoy a minute before they are baked. It is the boil- rick’s Day, you may see some bagels dyed typical city Sunday morning tradition and ing that gives them the sheen on the crust. green. Different cities have their own style of pick up the New York Times and a couple of True bagels have a dense chewy texture with bagels. In Chicago bagels are not boiled but bagels with a cream cheese and spend the a crust that has a slight snap when bitten. baked with steam, giving them a very soft rest of the morning relaxing with them. n 3 Photo Courtesy Michael of JosephPhoto Inner Sleeve of . Culture Corner Celebrating the 50th Anniversary of Beggars Banquet by B e r n i e L a ng s In December of 1968 The Roll- the late . Miller would go the moment called for it. In contrast, ing Stones released Beggars Banquet on to work with The Stones on their fin- the Stones stayed minimalistic on their just months before they would be in- est , including and records and could easily move from troduced as “the greatest rock and roll Exile on Main Street. served studio to stage with their tunes cen- band in the world.” The record, which as the studio engineer on Banquet and tered around two guitars, bass, drums, features tunes by the songwriting team provided piano for the and piano, with small horns thrown in of and at , shining on these tracks with his at times for variety. very peak of their creativity, has a con- individual style. The late Hopkins may Beggars kicks off with the infa- sistent, unified sound. Richards’ guitar have been the greatest keyboardist who mous “” which work on Beggars ranges from nuanced served as a hired hand for any major was viewed in 1968 as reflective of and subtle to in-your-face, airplane en- popular music band. the Stones’ image of danger and dark gine electric power chords, ringing out I was eleven years old when Beg- mystery. Even in my youth, however, I and enveloping Jagger’s vocals in a co- gars Banquet was released in America. was intrigued by the serious nature of coon of creative textures. My siblings and friends all knew that the lyrics and how deeply poetic they on drums and on bass an- this record was something special, ap- were in contrast to a lot of throw-away chor all of the music with exactitude pearing a year after The Beatles re- songs at the time. As Jagger steps into and precision. The band’s fifth member, leased their genius LP, Sgt. Pepper’s the guise of Lucifer, he’s more Oscar , was fading away at the time Lonely Hearts Club Band. Nothing on Wilde’s horrific gentleman Dorian of recording into an introverted state of Beggars was similar to Pepper’s. The Gray than a horror flick notion of the confusion and a paranoid drugged out compositions penned by Jagger and Devil. The character takes the listener haze. Jones only contributed here and Richards remained rooted in the chord on a tour of mankind’s violent history there, his last gasp of what he did best structures of traditional blues and also and sings with intensity as he describes as a musician, putting the cherry atop continued the Stones’ extrapolations on his role both as observer and bloody in- the sweet sundae of the Stones’ tracks. Chuck Berry’s “1-4-5” structure of ear- stigator. The song’s exotic descriptions It would be his final as a Stone, ly rock and roll composition, a pattern include gems such as “I lay traps for as he was asked to leave after the record also derived from the blues. Lennon troubadours who get killed before they was completed so the group could bring and McCartney’s songs on Pepper’s daz- reach Bombay” and “I watched in glee in virtuoso guitarist . Just zle in experimental melodic complexity as you kings and queens fought for ten a month after exiting the band, Jones amid George Martin’s nuanced produc- decades for the gods they made,” which died, drowning in his swimming pool. tion. Martin and The Beatles would se- may be the only reference in pop and Beggars Banquet was the first lectively celebrate their tracks with or- Stones album produced in the studio by chestral strings and woodwinds when CONTINUED TO P. 5 - 4 CONTINUED FROM P. 4 - one’s lost lover, the narrator of “No Door. to The Hundred Years’ War. Expectations” is broken-hearted and The greatest masterpiece song on Lucifer is a “beggar” who demands requests in the opening lines, “Take Beggars is “.” It is a sympathy for what he’s watched us do me the station and put me on a train, slice of English history in living color, and what he has had to endure. Yet I’ve got no expectation to pass through summing up the frustration of being a he also threatens that “if you meet me here again” and ends with a similar plea man with energy and new ideas have some courtesy, have some sympa- to be sent off far away in an airplane. in 1960s London. It speaks of revolu- thy, have some taste; use all your well- The song’s narrator describes the fleet- tion, revelation, rebellion, and resig- learned politeness, or I’ll lay your soul ing nature of the love he’s lost, “like the nation all in one set of lyrics. Even if to waste.” water, splashing on a stone” and notes, youth should run rampant through the Jean-Luc Godard, the French “Our love is like our music—it is here city streets and “kill the King” they will New Wave director, filmed the Stones and then it’s gone.” Brian Jones plays a ultimately be reduced to nothing more recording “Sympathy” and put some wicked slide acoustic guitar, which re- than bit players in a culturally limited of the footage in his movie “Sympathy solves on an “open” E chord that Keith rock and roll band. The sound of “Street for the Devil.” I find that movie ridicu- Richards must have been awed by, even Fighting Man” is the most complex in lous and unwatchable and wish some- through his anger with Jones’ continual terms of instrumentation on Beggars. one would extract the footage of the drugged out confusion. Charlie Watts and Keith Richards re- band, add moments that didn’t make The best acoustic performance corded their initial drums and acous- the final cut, and release it on its own on Beggars is, “Prodigal Son,” written tic guitars on a cassette recorder and (note that director Peter Jackson is cur- by , a reverend who re- Jimmy Miller manipulated that sound rently taking the best parts of footage corded in the 1920s and 1930s. I’m not to abstract perfection. Additional gui- of The Beatles’ mess of a 1970 docu- certain how old I was when I realized tars, percussion, and piano were added mentary “Let It Be” and adding many that the story of the song is Biblical, the later and Brian Jones contributed well- new scenes of them playing that were famous tale of the arrogant youth who placed drones on a . Jaggers’ vocals left on the cutting room floor). Go- leaves home to find the world a harsh, are menacing, multi-tracked, and star- dard captures how the band began with punishing place and later crawling back tlingly direct. I’ve listened to the song Mick Jagger strumming “Sympathy” to his father for forgiveness. Jagger sing- for fifty years and it is fresh on each on a guitar and how after some stan- ing affects a Southern, African-Amer- hearing. dard arrangements, the piece shifts to ican spiritualist tone and Richards’ Beggars closes out with a beauti- the heavy percussive Latin background acoustic chords and lead flourishes are ful song “Salt of the Earth,” an ode to sound, which is heard on the album. passionate and heartfelt. After Jagger’s the working class men and women of The congas and drums conjure the dev- last line, “My son was lost but now he Great Britain. At the same time, in the il like Shakespeare’s witches brewing is found” you can hear Richards give a song’s middle break Jagger admits that evil tidings from a boiling kettle. The guttural cry of “Hey!” as he brings it on while on stage performing, the crowd song builds to a frenzy and fades away home. One may venture that Mick and is nothing but a “swirling mass of grays with the singer’s echoing falsetto cries Keith would be absolutely content each and blacks and whites” that don’t seem as Lucifer spirals downwards to hell— day to sit on a porch in Mississippi in real to him and are actually “strange” in the band plays furiously amid Richard’s the summer sun, playing guitars and his eyes. The song hits a galloping peak sharp lead guitar work knifing through singing songs while swigging moon- and they give pianist Nicky Hopkins the mix. Lyrically, the words have more shine from a jug. the honor of having it fade out to his in common with England’s grand po- The rock songs on Beggars are manic right hand banging out a set of etic tradition than the good vibrations fantastic, especially “Parachute Wom- rapid chords. and flower power anthems spilling out an” and “.” “Stray Cat The album’s release was delayed on the radio at the time. If Bob Dylan Blues” in particular is an example of in 1968 because the record companies can win the Nobel Prize in literature for the Stones’ swaggering sexuality. When in America and Britain balked at the his groundbreaking lyrics, Jagger and I was teaching myself guitar as a teen- LP’s cover art of a dirty public bath- Richards surely qualify as Britain’s Poet ager, I would tune up to Beggars to play room with graffiti about the Stones and Laureates. along with the album, and the rhyth- the songs on Beggars. It was eventu- Beggars has fabulous moments of mic intensity of “” ally released with a white cover and a acoustic guitar-centered songs. After was difficult to master. When I finally mock invitation to the banquet. The in- “Sympathy” fades out, the next tune is got it down, it was almost as if the gui- ner sleeve, however, boasts a black and “,” a Jagger and Rich- tar took over in the song for itself, and white photo with shades of muted col- ards song that mirrors the classic “Love the intensity of the trancing repeating ors of the Stones celebrating like peas- in Vain” by American bluesman Rob- riffs brought me to a plane of surpris- ants who have invaded the King’s table ert Johnson. The Stones would record ing joy and newfound release. I could in the Dark Ages. It may be the great- “Love in Vain” for their next album, never truly master Keith’s leading stabs est match of image and personality in and while Johnson’s tune is in “Stray Cat Blues” but Jimmy Page a band in the history of rock music, a about unrequited love and features im- would give them homage on Led Zep- fitting idea for an incredible piece of ages of trains leaving the station with pelin’s final album, In Through the Out music. n 5 Pets of Tri-I Po oj a Vi s wa n at h a n

In this issue, Natural Selections inter- views Muffin and Velvet, the cats who live with Sarah Mereby (Fuchs Lab, The Rock- efeller University) and Eddie Spencer. I wasn’t able to meet these lovely creatures but Sarah graciously transmitted my questions to them and their answers to me. Please write me at [email protected]. edu if you have pets!

Pooja Viswanathan: How old are you? In hu- man years? Velvet: We are 21 years old and 1.5 years old in human years.

PV: Is there a story behind your names? V: I was named by the people that work at the shelter that I am from. It is very fitting since my coat is very soft and sleek. Muffin (left) and Velvet (right) Muffin: I was named by my hoomans. They told me I am super cute and small like a M: I love to eat canned cat food. I do not muffin. I’m not so small anymore though. have a favorite flavor. I eat so quickly that I can’t even remember what flavor I had or PV: What is your first memory? whether I had a full bowl to begin with. I M: My first memory was waking up to find also love to try to eat Velvet’s portion. Never I had been put in a mailbox in the middle know if Velvet had a better flavor or was of winter. I was so scared! Thankfully I given more food than me. was rescued by the local shelter, which led V: I love Friskies Shreds. My favorite flavor to me meeting my hoomans. Meeting my is salmon. I am very picky and have taught hoomans is my favorite memory. my hoomans to only give my shreds and not V: My first memory was meeting Muffin at pate. Ew. I also like treats: Ahi Tuna flavor! the shelter. The shelter told me that I was the I also like to drink water out of hooman’s only survivor of all my siblings. Muffin has glass. It always tastes best when it’s nice and been my friend and a part of my family ever cold. Sharing with hooman is the best. Al- since. though I don’t know why they get mad at me when I take a small lick of their water. PV: Which humans do you live with? When did you meet them? PV: What is your favorite weekend activity? V: We live with Sarah Mereby and Eddie V: We like to hang out with our hoomans on

Spencer. We met them at the shelter in Janu- the weekends. That’s the best. We normally Courtesy Sarah of Mereby Photos ary 2018. like to watch TV with hoomans and sit in Muffin (top) and Velvet (bottom). Photos our cat tree while looking out the window. by Sarah Mereby and Eddie Spencer. PV: How do they belong in the Tri-I commu- We also like to play with hooman. We love nity? our feather toys. slowly and pawed at it. We were worried we M: Sarah is a Research Specialist at The M: I like to snuggle with Eddie. were being replaced by a new cat. Thank- Rockefeller University. V: I like to follow hoomans everywhere fully it’s just a decoration. It wishes it could around the house to make sure to help them be like us. PV: Where do you live? if they need my assistance. V: We live in Montclair, NJ. We just moved PV: Is there some way we can see more pic- from Lyndhurst, NJ. We love our new house. PV: Besides your human roomie, who is your tures of you on the interwebs? We got to learn how to go up and down favorite human in the Tri-I community? V: You can follow us on the Instagram ac- stairs and there are so many new places for V: I have met Stephanie who works at Me- count @catasticday or use the hashtag #muf- us to hide. Also there are plenty of birds and morial Sloan Kettering. I love making new finandvelvet. squirrels to watch from the window. friends. M: I can’t remember. I am a bit afraid of PV: If you could have any human ability, what PV: If you could live anywhere else in the meeting new people. would it be? world, where would you live? M: Being able to open cans of cat food. That’s V: I would live wherever my hoomans and PV: Do you have a funny story to share with the dream. Muffin would live. us? V: Being able to play the piano. I love when M: I would live in a restaurant since I love to V: One time hoomans brought home a cat hoomans play piano. It’s very relaxing. I’ve eat and would help eat any leftovers. stuffed animal that is about the same size attempted to play the piano myself by jump- as us. We were so convinced it was real. It ing on the piano keys but it doesn’t sound as PV: What are your favorite foods? was very scary. We both approached it very good as when hooman plays. n 6 Life on a Roll Aurora over Snaefellsnes

M e ga n E l i z ab e t h K e l l e y (Tw i t t e r @M e ga n EK e l l e y)

On the Northern coast of the Snaefell- seemed to be a green spotlight blazing across snes peninsula in Iceland, there is a horse farm the sky. The wind and rain continued to blow nestled between the water and the mountains in from the side—I realized that I was still in where I stayed for a few nights. As is typical my pajamas and they were stacking up poorly for winter in Iceland, the wind howled, rain al- against the elements, but the awe-inspiring ternated with snow, and clouds often obscured sight of the aurora kept me outside for hours. I the stars, but for a few hours one night the skies was grateful when the clouds eventually rolled opened up and unveiled the Aurora Borealis. in over the mountains, as I needed sleep and At times, swirling light shimmered overhead could not have otherwise torn myself away like idle tracings, while at other times there from such a sight. n

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