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
  sectionsV2 {
    value {
      __typename
      ... on Section {
        name
        published
      }
      ... on VideoSection {
        name
        published
      }
      ...helpersCheckIfNewsSectionInFirstIndexSection
      ...entityLink
      ... on Node {
        __isNode: __typename
        id
      }
    }
  }
}

fragment articleSeoArticle_3o8td4 on Article {
  ...hooksArticleSeoArticle
  ...helpersGetArticleTypeArticle
  entityId
  publishedDate
  updatedDate
  summary {
    text
  }
  subHeadline {
    text
  }
  body(customContents: $customContents, type: $bodyType) {
    text
  }
  keywords
  sectionsV2 {
    value {
      __typename
      ... on Section {
        name
      }
      ... on Node {
        __isNode: __typename
        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
  }
  sectionsV2 {
    value {
      __typename
      ... on Section {
        relatedNewsletters {
          ...helpersMassageToNewsletterItemNewsletter
          id
        }
      }
      ... on Node {
        __isNode: __typename
        id
      }
    }
  }
  ... on Article {
    relatedNewsletters {
      ...helpersMassageToNewsletterItemNewsletter
      id
    }
  }
}

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

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

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
  ...helpersCheckIsPostMagazineArticle
  ...helpersCheckIsStyleArticle
  ...helpersSectionContent
  ...helpersStyleSectionContent
}

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

fragment helpersCheckIfNewsSectionInFirstIndexSection on SectionUnion {
  __isSectionUnion: __typename
  ... on Section {
    name
  }
  ... on VideoSection {
    name
  }
}

fragment helpersCheckIsAmpEnabledArticle on Article {
  entityId
  types {
    value {
      entityId
      id
    }
  }
  sectionsV2 {
    value {
      __typename
      ... on Section {
        entityId
      }
      ... on Node {
        __isNode: __typename
        id
      }
    }
  }
  disableOffPlatformContent
  sponsorType
  published
  ...helpersCheckIsPlusArticle
}

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 Content {
  __isContent: __typename
  sectionsV2 {
    value {
      __typename
      ... on Section {
        entityId
      }
      ... on Node {
        __isNode: __typename
        id
      }
    }
  }
}

fragment helpersCheckIsStyleArticle on Content {
  __isContent: __typename
  sectionsV2 {
    value {
      __typename
      ... on Section {
        entityId
      }
      ... on VideoSection {
        entityId
      }
      ... on Node {
        __isNode: __typename
        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 {
  ...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_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
  sectionsV2 {
    value {
      __typename
      ... on Section {
        name
      }
      ... on VideoSection {
        name
      }
      ... on Node {
        __isNode: __typename
        id
      }
    }
  }
  ...hooksContentHelperContent
}

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

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

fragment hooksPaywallPromiseContent on Content {
  __isContent: __typename
  entityId
}

fragment hooksTrackPageViewArticle on Content {
  __isContent: __typename
  entityId
  publishedDate
  headline
  sectionsV2 {
    value {
      __typename
      ... on Section {
        name
      }
      ... on Node {
        __isNode: __typename
        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
  }
}


types

sectionsV2

disableOffPlatformContent

sponsorType

published

headline

socialHeadline

authors

images

publishedDate

updatedDate

summary

subHeadline

keywords

topics

readingTime

authorLocations

Ling Xin

Chinese researchers have released the world’s first software for lunar timekeeping, a tool designed to support precise navigation and landings as a new global race to the moon gathers pace.
Clocks tick faster on the moon than on Earth due to weaker gravity – by about 56 millionths of a second per day. The effect, predicted by Albert Einstein’s theory of general relativity, is tiny but accumulates over time, making Earth time increasingly unreliable for lunar operations.
To address this, a team from the Purple Mountain Observatory in Nanjing built a model that accounts for both the moon’s weaker gravity and its motion through space, allowing events on the moon to be accurately synchronised with clocks used on Earth.
The researchers reported that their method remained accurate to within a few tens of nanoseconds even over 1,000 years, according to a paper published in the December issue of Astronomy and Astrophysics.
They also packaged the model into ready-to-use software, enabling users to compare lunar and Earth time in a single step instead of relying on complex calculations. The team said the goal was to make lunar timekeeping practical as missions to the moon become more frequent.
Jonathan McDowell, a Harvard astronomer and space historian, said lunar timekeeping was becoming a real engineering need rather than something that could be handled on a case-by-case basis using Earth time, as in the past.
Differences as small as a microsecond could quickly become significant in navigation systems, affecting calculations over timescales of a minute, he said.
“If you want to use the equivalent of GPS on the moon – which we’ll probably want to do in just a few years from now, especially for precision landing locations – you’ll need to handle this somehow.”


McDowell said while similar work had been under way in the US, he was not aware of another readily available tool. “This emphasises that China is serious about the moon, and is being quite open about sharing its lunar-related research,” he said.
In the past, the fact that clocks tick differently on the moon and on Earth mattered little because lunar missions were rare. Engineers simply used Earth time and applied corrections for each mission when needed.
That approach is becoming harder to sustain. As more spacecraft – and eventually people – are expected to operate on and around the moon at the same time, relying on ad hoc fixes would quickly become unwieldy.
To prepare for that future, the International Astronomical Union adopted a broad framework in 2024 calling for the moon to have its own time reference.
Building on that framework, the Chinese team set out to turn the idea into something engineers could actually use. They began by using precise data on the moon’s motion to track how the time difference between the moon and Earth changes over time.
They then wrapped those calculations into a software package that automates the process, allowing users to compare lunar and Earth time directly instead of performing complex calculations themselves.
The team named the software LTE440, short for Lunar Time Ephemeris. They noted that it was an early step and would need to be extended to support real-time navigation and future lunar clock networks.


China unveils world’s first timekeeping software for the moon, where clocks ticks faster

Chinese scientists have developed a world-first tool to accurately synchronise time on the moon with clocks on Earth, to help with space missions and precision location landing. Photo: Getty Images / iStockphoto

News

China

Science

New tech allows moon events to be accurately synchronised from Earth, paving the way for more spacecraft and people to work on the satellite


New tech allows moon events to be accurately synchronised from Earth, paving the way for more spacecraft and people to work on the satellite.


Harvard Medical School

China unveils world’s first timekeeping software for the moon, where clocks ticks faster

.css-1c6uqr6{color:inherit;font-weight:inherit;font-size:inherit;font-family:inherit;line-height:inherit;overflow-wrap:break-word;}New tech allows moon events to be accurately synchronised from Earth, paving the way for more spacecraft and people to work on the satellite

New tech allows moon events to be accurately synchronised from Earth, paving the way for more spacecraft and people to work on the satellite