bodyType

customContents

entityId

printArticlePageQuery

filter

article

body

urlAlias

articleSectionsContent

articleSeoArticle

articleSourceHeaderArticle

contentSchemaRenderContent

contentSubHeadlineContent

contentHeadlineContent

mainImagePrintArticleArticle

authorBlockPrintArticleArticle

contentSponsorTagContent

articlePianoPaywallContent

scmpYoutubeContent

hooksTrackPageViewArticle

query printArticlePageQuery(
  $entityId: String!
  $customContents: [CustomContentInput]
  $bodyType: BodyFormatTypeEnum
) {
  article(filter: {entityId: $entityId}) {
    entityId
    body(customContents: $customContents, type: $bodyType) {
      json
    }
    urlAlias
    ...articleSectionsContent
    ...articleSeoArticle_3o8td4
    ...articleSourceHeaderArticle
    ...contentSchemaRenderContent
    ...contentSubHeadlineContent
    ...contentHeadlineContent
    ...mainImagePrintArticleArticle
    ...authorBlockPrintArticleArticle
    ...contentSponsorTagContent
    ...articlePianoPaywallContent
    ...scmpYoutubeContent
    ...hooksTrackPageViewArticle
    id
  }
}

fragment articlePianoPaywallContent on Content {
  __isContent: __typename
  ...hooksPaywallPromiseContent
}

fragment articleSectionsContent on Content {
  __isContent: __typename
  sections {
    value {
      ...helpersCheckIfNewsSectionInFirstIndexSection
      ...entityLink
      name
      id
    }
  }
}

fragment articleSeoArticle_3o8td4 on Article {
  ...hooksArticleSeoArticle
  ...helpersCheckIsPostiesArticle
  ...helpersGetArticleTypeArticle
  entityId
  publishedDate
  updatedDate
  summary {
    text
  }
  subHeadline {
    text
  }
  body(customContents: $customContents, type: $bodyType) {
    text
  }
  keywords
  sections {
    value {
      name
      id
    }
  }
  topics {
    name
    entityId
    id
  }
  urlAlias
  authors {
    name
    id
  }
  images {
    style(filter: {style: "768x768"}) {
      url
    }
  }
  readingTime
}

fragment articleSourceHeaderArticle on Article {
  urlAlias
  ...entityLink
}

fragment authorBlockPrintArticleArticle on Article {
  ...defaultArticleDateContent
  ...authorNamesArticle
}

fragment authorNameAuthor on Author {
  ...entityLink
  name
  entityUuid
}

fragment authorNamesArticle on Article {
  authorLocations
  authors {
    entityId
    location
    ...authorNameAuthor
    id
  }
}

fragment blockquoteQuoteContent on Content {
  __isContent: __typename
  ...contentShareWidgetContent
}

fragment checkersCheckContentContainsStarlingImageContent on Content {
  __isContent: __typename
  topics {
    entityId
    id
  }
}

fragment contentHeadlineContent on Content {
  __isContent: __typename
  headline
  socialHeadline
  ...contentHeadlineTagContent
  ...helpersUseContentSponsorContent
}

fragment contentHeadlineTagContent on Content {
  __isContent: __typename
  ...hooksContentHeadlineTagContent
}

fragment contentNewsletterWidgetContent on Content {
  __isContent: __typename
  topics {
    relatedNewsletters {
      ...helpersMassageToNewsletterItemNewsletter
      id
    }
    id
  }
  sections {
    value {
      relatedNewsletters {
        ...helpersMassageToNewsletterItemNewsletter
        id
      }
      id
    }
  }
  ... on Article {
    relatedNewsletters {
      ...helpersMassageToNewsletterItemNewsletter
      id
    }
  }
}

fragment contentSchemaRenderContent on Content {
  __isContent: __typename
  ...blockquoteQuoteContent
  ...imageContent
  ...inlineWidgetContent
  ...photoGalleryWidgetContent
  ...scmpYoutubeContent
}

fragment contentShareWidgetContent on Content {
  __isContent: __typename
  entityId
  urlAlias
  shortUrl
  socialHeadline
  headline
}

fragment contentSponsorTagContent on Content {
  __isContent: __typename
  ...helpersUseContentSponsorContent
}

fragment contentSubHeadlineContent on Content {
  __isContent: __typename
  subHeadline {
    json
  }
  summary {
    json
  }
  ...contentSchemaRenderContent
}

fragment defaultArticleDateContent on Content {
  __isContent: __typename
  ...hooksArticleDateUtilsContent
}

fragment entityLink on BaseWithApplicationAndUrlAlias {
  __isBaseWithApplicationAndUrlAlias: __typename
  __typename
  entityId
  entityUuid
  urlAlias
  urlRedirect {
    toUrl
    id
  }
  application {
    entityId
    id
  }
  ... on Section {
    fullSectionPath {
      entityId
      id
    }
    parentSection
  }
  ...helpersAppBarVariantBase
  ...helpersApplicationBase
  ...helpersCheckIsPlusArticle
  ...helpersStyleSectionContent
}

fragment helpersAppBarVariantBase on BaseWithApplicationAndUrlAlias {
  __isBaseWithApplicationAndUrlAlias: __typename
  ...helpersCheckIsLiveArticle
  ...helpersCheckIsPlusPage
  ...helpersCheckIsPostiesArticle
  ...helpersCheckIsPostiesPage
  ...helpersCheckIsPostMagazineArticle
  ...helpersCheckIsStyleArticle
  ...helpersSectionContent
  ...helpersStyleSectionContent
}

fragment helpersApplicationBase on BaseWithApplicationAndUrlAlias {
  __isBaseWithApplicationAndUrlAlias: __typename
  ...helpersCheckIsPostiesArticle
  ...helpersCheckIsPostiesPage
  ...helpersCheckIsPlusPage
}

fragment helpersCheckIfNewsSectionInFirstIndexSection on Section {
  name
}

fragment helpersCheckIsAmpEnabledArticle on Article {
  entityId
  types {
    value {
      entityId
      id
    }
  }
  sections {
    value {
      entityId
      id
    }
  }
  disableOffPlatformContent
  sponsorType
  published
  ...helpersCheckIsPlusArticle
  ...helpersCheckIsPostiesArticle
}

fragment helpersCheckIsLiveArticle on Article {
  flattenTypeIds
  liveArticle {
    status
    id
  }
}

fragment helpersCheckIsMainTopicContent on Content {
  __isContent: __typename
  topics {
    entityId
    id
  }
}

fragment helpersCheckIsPlusArticle on Content {
  __isContent: __typename
  ... on Article {
    paywallTypes {
      entityUuid
      id
    }
  }
}

fragment helpersCheckIsPlusPage on Page {
  urlAlias
}

fragment helpersCheckIsPostMagazineArticle on Article {
  sections {
    value {
      entityId
      id
    }
  }
}

fragment helpersCheckIsPostiesArticle on Article {
  sections {
    value {
      entityId
      id
    }
  }
}

fragment helpersCheckIsPostiesPage on Page {
  urlAlias
}

fragment helpersCheckIsStyleArticle on Content {
  __isContent: __typename
  sections {
    value {
      entityId
      id
    }
  }
}

fragment helpersGetArticleTypeArticle on Content {
  __isContent: __typename
  ... on Article {
    types {
      value {
        entityId
        id
      }
    }
  }
}

fragment helpersMassageToNewsletterItemNewsletter on Newsletter {
  entityId
  name
  alternativeName
  description {
    text
  }
  summary {
    text
  }
  homepageDescription {
    text
  }
}

fragment helpersSanitizeArticleTypeEntityIdsArticle on Article {
  types {
    value {
      entityId
      id
    }
  }
}

fragment helpersSanitizeAuthorTypesArticle on Article {
  authors {
    types
    id
  }
}

fragment helpersSanitizedAuthorEntityIdsArticle on Article {
  authors {
    entityId
    id
  }
}

fragment helpersSectionContent on Section {
  fullSectionPath {
    entityId
    id
  }
}

fragment helpersStyleSectionContent on Section {
  fullSectionPath {
    entityId
    id
  }
}

fragment helpersUseContentSponsorContent on Content {
  __isContent: __typename
  topics {
    entityId
    sponsor {
      ...sponsorTagSponsor
      name
      type
      id
    }
    id
  }
  ... on Article {
    sponsorType
  }
  ...helpersCheckIsMainTopicContent
}

fragment hooksArticleDateUtilsContent on Content {
  __isContent: __typename
  createdDate
  publishedDate
  updatedDate
}

fragment hooksArticleSeoArticle on Article {
  ...helpersCheckIsPostiesArticle
  ...helpersCheckIsPostMagazineArticle
  ...helpersCheckIsStyleArticle
  ...hooksContentHeadlineTagContent
  ...helpersCheckIsAmpEnabledArticle
  entityId
  headline
  socialHeadline
  types {
    value {
      entityId
      id
    }
  }
  authors {
    entityId
    id
  }
  images {
    generic_og: style(filter: {style: "og_image_scmp_generic"}) {
      url
    }
    styles(filter: {styles: ["og_image_posties_article", "og_postmag", "og_image_style", "og_image_scmp_analysis", "og_image_scmp_explainer", "og_image_scmp_editorial", "og_image_scmp_fact_check", "og_image_scmp_debate", "og_image_scmp_live", "og_image_scmp_obituary", "og_image_scmp_opinion", "og_image_scmp_review", "og_image_scmp_series", "og_image_scmp_generic"]}) {
      url
      style
    }
    type
  }
  urlAlias
}

fragment hooksContentHeadlineTagContent on Content {
  __isContent: __typename
  __typename
  ... on Article {
    types {
      value {
        name
        entityId
        description {
          text
        }
        id
      }
    }
    ...helpersCheckIsStyleArticle
  }
  flag
  sections {
    value {
      name
      id
    }
  }
  ...hooksContentHelperContent
}

fragment hooksContentHelperContent on Content {
  __isContent: __typename
  ...helpersSanitizeArticleTypeEntityIdsArticle
  ...helpersSanitizeAuthorTypesArticle
  ...helpersSanitizedAuthorEntityIdsArticle
  flag
}

fragment hooksPaywallPromiseContent on Content {
  __isContent: __typename
  entityId
  ...helpersCheckIsPostiesArticle
}

fragment hooksTrackPageViewArticle on Article {
  entityId
  publishedDate
  headline
  sections {
    value {
      name
      id
    }
  }
  urlAlias
  authors {
    name
    id
  }
  entityUuid
}

fragment imageContent on Content {
  __isContent: __typename
  headline
  ...checkersCheckContentContainsStarlingImageContent
}

fragment inlineWidgetContent on Content {
  __isContent: __typename
  ...contentNewsletterWidgetContent
}

fragment mainImagePrintArticleArticle on Article {
  images {
    title
    url
    isSlideshow
    size_652x446: style(filter: {style: "652x446"}) {
      url
    }
  }
}

fragment photoGalleryDialogContent on Content {
  __isContent: __typename
  __typename
  ...contentShareWidgetContent
}

fragment photoGalleryWidgetContent on Content {
  __isContent: __typename
  ...photoGalleryDialogContent
}

fragment scmpYoutubeContent on Content {
  __isContent: __typename
  entityId
  urlAlias
  publishedDate
}

fragment sponsorTagSponsor on Sponsor {
  name
  type
  images {
    url
  }
}


sections

types

disableOffPlatformContent

sponsorType

published

headline

socialHeadline

authors

images

publishedDate

updatedDate

summary

subHeadline

keywords

topics

readingTime

authorLocations

entityUuid

Sarah Kaplan

Something strange is sailing towards us. Something small and cold and extraordinarily fast. No one knows where it came from, or where it is going. But it’s not from around here.
This is an interstellar comet – an ancient ball of ice and gas and dust, formed on the frozen outskirts of a distant star, which some lucky quirk of gravity has tossed into our path.
To astronomers, the comet is a care package from the cosmos – a piece of a place they will never be able to visit, a key to all the worlds they cannot directly observe.
It is only the second interstellar interloper scientists have seen in our solar system. And it’s the first one they’ve been able to get a good look at. By tracking the comet’s movement, measuring its composition and monitoring its behaviour, researchers are seeking clues about the place it came from and the space it crossed to get here. They have already found a carbon-based molecule and possibly water – two familiar chemicals in such an alien object.
Wow. I was not expecting to see anything like that
Davide Farnocchia, navigation engineer, Nasa’s Jet Propulsion Laboratory
As the sun sinks behind the mountains in the American state of Tennessee, and stars wink into view, astronomer Doug Durig climbs onto the rooftop of his observatory, powers up his three telescopes and angles them skyward.
Every night, the comet grows bigger and brighter, expelling streams of gas and dust that may offer up clues to its history. On December 8, it was due to make its nearest approach to Earth, offering researchers an up-close glimpse before zooming back into the freezing, featureless void.
Far below in the darkness, Durig was waiting.
Surviving close encounter with the sun, Nasa probe sends home surprise findings
Each star in the night sky represents a possible solar system. Every light in the universe is, more likely than not, some alien planet’s sun.
This is the chief lesson of two decades of studying exoplanets. Scientists have identified thousands of worlds beyond our solar system: gas giants and tiny rocky spheres, worlds lit by dim red suns and ones that orbit the spinning remains of collapsed stars. There are even planets circling medium-size yellow suns like ours – though nothing found so far can match the breathable atmosphere and deep, blue oceans of Earth.
Yet even when viewed through the most powerful telescopes, exoplanets are not discernible as anything more than specks of light. And no human alive has a hope of travelling to another star – merely approaching the nearest one would take 40,000 years.
Scientists’ best hope for closely examining another solar system was to wait for a piece of one to come to us.
It was August 30, in the quiet moments before dawn, when a self-taught astronomer in a Crimean mountain village spotted a faint smudge low on the horizon, barely distinguishable against the glittering background of stars.
Gennady Borisov submitted his observations to the Minor Planet Centre, the astronomers’ clearing house for information about small bodies in the solar system, so other scientists could take a look.
One night later, halfway across the planet, the strange report caught Durig’s eye.
“I was the second person to observe it,” Durig says. “That confirmed the comet was real.”
Within a couple of weeks, scientists had collected enough observations to calculate the comet’s orbit. But they did not find the oval path that comets typically make around the sun. Instead, the orbit was hyperbolic – it did not close in on itself. The object was also travelling at the blistering speed of 149,669km/h (93,000 miles per hour), far faster than any comets, asteroids or planets orbiting our sun.
“Wow,” says Davide Farnocchia, a navigation engineer at Nasa’s Jet Propulsion Laboratory, who was among the first people to determine that the comet came from another star. “I was not expecting to see anything like that.”

There has been only one other interstellar object spotted in our solar system: a cigar-shaped rock named ‘Oumuamua, a Hawaiian word that translates to “messenger from afar”.
But ‘Oumuamua was already on its way out of the system when it was discovered, in October 2017, and it was so faint that scientists were never able to view it as more than a single pixel of light. They were not quite sure what they had seen – was it a metallic, rocky asteroid or an icy, dusty comet? And they were unsure whether the detection was just a lucky fluke, never to be repeated, or a harbinger of things to come.
So researchers were thrilled when, less than two years later, another interstellar traveller arrived.
The new comet, which has been named 2I/Borisov (indicating its discoverer and its status as the second known interstellar object), is expected to be within reach of telescopes until autumn 2020. At its closest approach, it would be twice as far from Earth as Earth is from the sun.
Though it entered the solar system from the direction of the constellation Cassiopeia, scientists do not know yet where 2I/Borisov came from, or how long it has drifted through the desolation of interstellar space. Given its current speed, it has certainly been travelling for millions, if not billions, of years.
It used to seem like planet formation was solved and then all of a sudden there are all these strange systems that don’t fit our picture
Malena Rice, astrophysicist, Yale University
As the object gets closer to the sun’s warmth, ice on its surface turns into gas. This creates the characteristic halo-like “coma”, which scientists can scrutinise to determine what the comet is made of. Already, 2I/Borisov has been observed more than 2,000 times.
“That’s going to be fun, in terms of looking at this object […] as it comes in from the deep freeze for the very first time,” says Michele Bannister, an astronomer at Queen’s University Belfast. “Let’s open it up and see what we have with this particular present from another star.”
Exoplanet discoveries revealed we live in a crowded cosmos. But they also awakened Earthlings to how lonely we are. Most planetary systems discovered in recent decades are wildly unfamiliar, and the most common type of exoplanet – a body larger than Earth but smaller than Neptune – doesn’t exist near our home.
When astronomers had only our own solar system to go by, “it used to seem like planet formation was solved”, says Malena Rice, an astrophysicist at Yale University. “And then all of a sudden there are all these strange systems that don’t fit our picture.”
Interstellar comets are useful for confronting this conun­drum. They are born of the same swirling disk of gas and dust that produces planets around an infant star. But then they get stranded at the icy edges of solar systems, where they can preserve the ingredients of planet formation.
Chinese astronomers discover ‘impossibly massive’ black hole
Comets in our own solar system have been found to contain some of the basic ingredients for life: water, carbon, even complex organic compounds. Now 2I/Borisov could tell us whether life’s essential molecules were among the building blocks of a world beyond our own.
This autumn, Bannister’s colleague Alan Fitzsimmons produced the first-ever detection of a chemical compound emitted by an interstellar comet. Separating light from 2I/Borisov into its component parts, his team found a signa­ture of cyanogen, a molecule made of a carbon atom and a nitrogen atom bonded together. The gas is common in comets around this sun.
“When I saw that, I shouted in my office, something not repeatable in a respectable newspaper,” Fitzsimmons says.
A few weeks later, astronomer Adam McKay detected oxygen streaming off the comet, an indicator that sunlight is striking water on the surface and breaking up the molecule. If confirmed, this would be the first-ever detection of alien water in our solar system. It is also another sign that 2I/Borisov is much like the comets we know.
“Even in these other systems where their architectures are very different, maybe the underlying physics and chemistry is still pretty similar,” says McKay, a research scientist at Nasa’s Goddard Space Flight Centre.

Models of our solar system suggest that about 90 per cent of the leftover material from planet formation is ejected into interstellar space. The space beyond Neptune still harbours millions of icy bodies, which over millennia can be knocked out of orbit and slung away from the sun.
If any of these scattered fragments happen to be pulled into another system and start to glow in the heat of its star, they will appear as interstellar comets to whoever might be watching.
“There’s a universality to that, which is amazing,” Bannister says. “Our planetary system is woven together with another planetary system by these little wanderers roving across the galaxy.”
With just an hour to go until daybreak, 2I/Borisov is due to appear above the horizon and make its way across the eastern sky. Durig’s long night is almost over.
Sewanee: The University of the South, the 1,600-student liberal arts college where Durig works, does not have the massive instruments needed to resolve faint night-sky objects. Instead, he must take hundreds of images of the same spot, then use a computer programme to layer them so dim lights become clear.
The astronomer checks the focus of his 12-inch Schmidt-Cassegrain telescope and sets it to work, snapping pictures of the place where the interstellar comet is expected to be. He rubs a hand across his eyes, itchy from hours spent under the dim red lights he uses to protect his night vision.
Scientists map Saturn’s exotic moon Titan in search of life
It is tiring and often tedious work. Unlike discoverers, follow-up observers do not get to put their names on anything. And unlike researchers working at the world’s largest observatories, someone such as Durig faces real hurdles in achieving the findings that get published in prestigious journals.
Still, extraordinary discoveries must be confirmed and refined, again and again, by ordinary people. News may be made by breakthroughs, but knowledge is cemented in the follow-ups.
Here in Sewanee’s cramped observatory, cluttered with stacks of observation records and piles of broken equip­ment he hopes to one day refashion into something usable, “we’re doing essential science”, Durig says. “We’re filling in all the gaps.”
Once his telescope has captured an hour’s worth of snapshots, Durig compiles them into stacks of 100. In the images that emerge, colours are inverted, so stars appear as black smears on a white background. In the lower left is a dark dot encircled in a halo of fuzz.
Durig clicks forward to the next stack, and the dot moves by a centimetre. Another click, and it moves again.
That’s how he knows he is looking at the comet, something swift and surrounded by dust, something that behaves like nothing else in the sky.
Durig sends his images and a record of the comet’s location to the Minor Planet Centre – another drop of data in the bucket of scientific knowledge.

Consistent observations like this, conducted by the same people using the same instruments every night, will be even more important once the comet becomes visible in the southern hemisphere, where many of the world’s biggest telescopes are positioned.
They need to be pointed with extreme precision, so astronomers must have a firm handle on the comet’s trajectory and things that might subtly alter it, such as outbursts of gas.
An accurate orbit is also key to astronomers’ most ambitious plan for the comet.
“If we can get the best possible trajectory, so we can trace it back with the exact direction it’s coming in […] maybe we can find out what the origin system is,” says Farnocchia, the Jet Propulsion Laboratory engineer.
Identifying the comet’s parent star would be a tremendous feat, the astronomical equivalent of tracing a message in a bottle back to the person who sent it millions of years ago from billions of kilometres away. It may not be possible, most scientists acknowledge.
But maybe that’s OK, they say. Because the comet will have already revealed so much else. It will have told us something about the birth of solar systems. It will have connected our home to the workings of the wider galaxy. And now that we have seen it, it is easier to believe that more are out there to be found.
Here on Earth, together in the darkness, Durig and his fellow astronomers will be waiting.
Text: The Washington Post


Could comet 2I/Borisov, currently coursing through our solar system, hold cosmic secrets?

Astronomer Doug Durig waits in darkness for images of the comet object 2I/Borisov, on October 3, in Sewanee, Tennesse, in the United States. Photo: Washington Post / Sarah Kaplan

Interstellar Interloper 2I/Borisov. MUST CREDIT: NASA, ESA, and D. Jewitt (UCLA) et al

The path of comet 21/Borisov through our Solar System. The panel at left shows the comet's straight path across interstellar space slightly deflected by the sun's gravitational pull. The panel at right shows the comet's position relative to Earth when the NASA/ESA Hubble Space Telescope observed it on Oct. 12, 2019, when it was almost 261 million miles (420 million kilometers) from Earth. MUST CREDIT: NASA, ESA, J. Olmsted, F. Summers (STScI)

This artist's impression shows the first-known interstellar object to visit the solar system, 'Oumuamua, which was discovered on October 19, 2017, by the Pan-STARRS 1 telescope in Hawaii, U.S., with subsequent observations from ESO's Very Large Telescope in Chile and other observatories around the world. European Southern Obervatory/M. Kornmesser/Handout via REUTERS ATTENTION EDITORS - THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY.

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First spotted on August 30, from a Crimean mountain village, the comet has been travelling for millions, if not billions, of years
For astronomers, it is a care package from the cosmos – a key to worlds they cannot directly observe



First spotted on August 30 from Crimea by a self-taught astronomer, comet 2I/Borisov holds a key to worlds astronomers cannot directly observe.


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Could comet 2I/Borisov, currently coursing through our solar system, hold cosmic secrets?

First spotted on August 30, from a Crimean mountain village, the comet has been travelling for millions, if not billions, of years For astronomers, it is a care package from the cosmos – a key to worlds they cannot directly observe

First spotted on August 30, from a Crimean mountain village, the comet has been travelling for millions, if not billions, of years

For astronomers, it is a care package from the cosmos – a key to worlds they cannot directly observe