Wednesday, 2 January 2019

Earth approaches perihelion.

On Thursday 3 January 2019 at 5.21 am, GMT, the Earth will reach its perihelion; the closest point on its orbit to the Sun, when it will be 147 099 760 km from the Sun. This is because the Earth's orbit is not a perfect circle, but varies by 3.3% over the course of a year. The Earth will reach its furthest point from the Sun, at a distance of 152 095 566 km, at 5.46 pm GMT on 6 July 2016. This perihelion distance varies each year; in 2018 the Earth reached 147 097 233 from the Sun and in 2020 it will reach 147 084 627. 

The Earth's Aphelion and Perihelion. My Dark Sky.

This means that the Earth is at its closest to the Sun in the middle of the Northern Hemisphere's winter, counter-intuitive to most of the planet's population. This is, however, purely coincidental; the Earth's season's are not caused by its distance from the Sun, which only varies by 3.3%, but rather by the tilt of the planet. The Earth is currently tilted at an angle of 25.5° to its plane of orbit (this varies on a timescale of tens of thousands of years, but remains fixed from the point of view of any human observer), causing the Sun to appear to rise higher and lower in the skies of each hemisphere as the year goes by. In the northern winter the Southern Hemisphere is tilted towards the Sun, so that the days are longer there (and in around the Southern Solstice in December, permanently above the horizon at the South Pole). In addition the Sun being directly overhead means that the energy from the Sun has to pass through less of the atmosphere before it reaches the surface of the Earth, so that less energy is lost to the atmosphere, causing the surface to warm.

 How the tilt of the Earth relative to its plane of orbit causes the seasons. ESA.

See also...

https://sciencythoughts.blogspot.com/2018/12/the-december-solstice.htmlhttps://sciencythoughts.blogspot.com/2018/09/the-september-equinox.html
https://sciencythoughts.blogspot.com/2018/08/partial-solar-eclipse-to-be-visible.htmlhttps://sciencythoughts.blogspot.com/2018/07/total-lunar-eclipse-to-be-visible-from.html
https://sciencythoughts.blogspot.com/2018/07/partial-solar-elipse-to-be-visible-from.htmlhttps://sciencythoughts.blogspot.com/2018/06/northern-solstice-2018.html
Follow Sciency Thoughts on Facebook.

2 comments:

  1. Hi Joe,
    Happy new year!
    You wrote:
    The Earth is currently tilted at an angle of 25.5° to its plane of orbit
    from Wikipedia:Earth's obliquity oscillates between 22.1 and 24.5 degrees[2] on a 41,000-year cycle; Earth's mean obliquity is currently 23°26′12.6″ (or 23.43682°) and decreasing.

    ReplyDelete
    Replies
    1. KARNA RASA HATI YANG GEMBIRA BERKAT BANTUAN AKI SOLEH
      MAKANYA SENGAJA NAMA BELIAU SAYA CANTUNKAN DI INTERNET…!!!!

      assalamualaikum wr, wb, saya IBU SUSANTI TKI JEDAH saya Mengucapkan banyak2
      Terima kasih kepada: AKI SOLEH
      atas nomor togelnya yang kemarin AKI berikan "4D"
      alhamdulillah ternyata itu benar2 tembus AKI
      dan berkat bantuan AKI SOLEH saya bisa melunasi semua hutan2…
      orang tua saya yang ada di BANK BRI dan bukan hanya itu AKI alhamdulillah,
      sekarang saya sudah bisa bermodal sedikit untuk mencukupi kebutuhan keluarga saya sehari2.
      Itu semua berkat bantuan AKI SOLEH sekali lagi makasih banyak ya, AKI
      yang ingin merubah nasib
      seperti saya...?
      SILAHKAN GABUNG SAMA AKI SOLEH No; { 082-313-336-747 }

      Sebelum Gabung Sama AKI Baca Duluh Kata2 Yang Dibawah Ini
      Apakah anda termasuk dalam kategori di bawah ini...!!
      1: Di kejar2 tagihan hutang..
      2: Selaluh kalah dalam bermain togel
      3: Barang berharga sudah
      terjual buat judi togel..
      4: Sudah kemana2 tapi tidak
      menghasilkan, solusi yang tepat..!
      5: Sudah banyak dukun ditempati minta angka ritual blom dapat juga,
      6: Pelet pemikat hati untuk pria
      7: Pesugihan tanpah tumbal
      8: Dukun santet paling ampuh
      satu jalan menyelesaikan masalah anda..
      Dijamin anda akan berhasil
      silahkan buktikan sendiri
      Atau Chat/Tlpn di WhatsApp (WA)
      No WA Aki : 082313336747

      TERIMA KASIH YANG PUNYA
      ROOM ATAS TUMPANGANYA SELAM KOMPAK SELALU

      (1) "http://angkaramalantogel.blogspot.co.id/"

      (2) "Pelet Khusus Untuk Memikat Hati Pria"

      (3) "Ilmu Santet Ganas"

      (4) "Asli Pusat Pesugihan Putih Tampa Tumbal"

      Delete