The comet Honda-Mrkos-Pajdusakova is expected to brighten rapidly in August as it passes to the south of the Earth. It will be observable from the southern hemisphere for about 2 weeks before getting too close to the Sun.

At its closest the comet will be 0.060 AU from the Earth, that is about 9 million kilometers away. While this is close for a comet, it is still about 24 times the distance of the moon. When it is first at magnitude 10, on the evening of August 9/10 it will be visible from New Zealand throughout the night, setting only briefly during daylight hours. For the next few nights until August 16 it will be circumpolar although low in the sky in the evening. On the 17th it will set briefly in the evening to rise again about midnight.

Over the next few days, as the comet moves north it will rise after midnight so becoming a morning object. Its elongation from the Sun will decrease as the comet moves away from the Earth towards the Sun and it will rise later in the morning to become lost in the morning twilight by about August 23.

By mid September Honda-Mrkos-Pajdusakova will be an 8th magnitude object rising about 90 minutes before the Sun into the dawn sky. The comet will then be slow moving in Leo, a few degrees from Regulus. By mid October it will have faded to magnitude 10. (RASNZ)

The chart presents a view looking to the south in the evening at about 8 pm. The position of the comet is marked for each evening at this time. Stars to magnitude 7.50 are shown, with magnitudes labelled for stars brighter than magnitude 5.0.
The circle on the chart represents a field of view 5° in diameter, a fairly typical field of view for binoculars.

JPL Small-Body Database Browser

45P/Honda–Mrkos–Pajdušáková is a short-period comet discovered by Minoru Honda December 3, 1948. The comet is named after Minoru Honda, Antonín Mrkos, and Ľudmila Pajdušáková. The comet is on a elliptical orbit with a period of 5.26 years.  The comet nucleus is estimated to be 0.5-1.6 kilometers in diameter. During the 2011 perihelion passage the comet was recovered on 05 June 2011 at apparent magnitude 21. On 8 July 2011 the comet had a magnitude of approximately 18,  and as of 22 July 2011 the comet’s nuclear condensation has a magnitude of approximately 16.  The comet is expected to reach a peak magnitude of around 7.3 in late September when it is near perihelion.

The comet will make a close approach of only 0.0600 AU (8,980,000 km; 5,580,000 mi) from the Earth on August 15, 2011, and will be studied by the Goldstone Deep Space Network on August 19th and 20th. It will also pass close to Earth on February 11, 2017. 

During the 1995 perihelion passage the comet was visible to Solar and Heliospheric Observatory (SOHO) on January 16, 1996 when the comet was around apparent magnitude 7 and 4.3° from the Sun. (Wikipedia)

This comet made 11 close approaches to Earth and 2 close approaches to Jupiter during the 20th century. It makes 1 close approach to Venus, 5 close approaches to Earth, and 1 close approach to Jupiter during the first half of the 21st century. (Cometography)

  • 0.62 AU from Earth on 1900 July 31
  • 0.64 AU from Earth on 1906 March 20
  • 0.26 AU from Earth on 1917 January 16
  • 0.35 AU from Earth on 1927 November 24
  • 0.08 AU from Jupiter on 1935 August 15
    • decreased perihelion distance from 0.64 AU to 0.58 AU
    • decreased orbital period from 5.53 to 5.27 years
  • 0.83 AU from Earth on 1943 July 12
  • 0.43 AU from Earth on 1948 November 16 (contributed to comet’s discovery)
  • 0.59 AU from Earth on 1954 March 15
  • 0.30 AU from Earth on 1969 August 11
  • 0.23 AU from Earth on 1975 February 5
  • 0.11 AU from Jupiter on 1983 March 26
    • decreased perihelion distance from 0.58 AU to 0.54 AU
    • increased orbital period from 5.28 to 5.30 years
  • 0.29 AU from Earth on 1990 August 1
  • 0.17 AU from Earth on 1996 February 4
  • 0.09 AU from Venus on 2006 June 4
  • 0.06 AU from Earth on 2011 August 15
  • 0.09 AU from Earth on 2017 February 11
  • 0.57 AU from Earth on 2027 July 20
  • 0.17 AU from Jupiter on 2030 August 3
    • increased perihelion distance from 0.56 AU to 0.63 AU
    • increased orbital period from 5.34 to 5.52 years
  • 0.37 AU from Earth on 2032 November 6
  • 0.39 AU from Earth on 2043 November 21

If you value what we do here, create your ad-free account and support our journalism.


Producing content you read on this website takes a lot of time, effort, and hard work. If you value what we do here, select the level of your support and register your account.

Your support makes this project fully self-sustainable and keeps us independent and focused on the content we love to create and share.

All our supporters can browse the website without ads, allowing much faster speeds and a clean interface. Your comments will be instantly approved and you’ll have a direct line of communication with us from within your account dashboard. You can suggest new features and apps and you’ll be able to use them before they go live.

You can choose the level of your support.

Stay kind, vigilant and ready!

$5 /month

  • Ad-free account
  • Instant comments
  • Direct communication
  • New features and apps suggestions
  • Early access to new apps and features

$50 /year

$10 /month

  • Ad-free account
  • Instant comments
  • Direct communication
  • New features and apps suggestions
  • Early access to new apps and features

$100 /year

$25 /month

  • Ad-free account
  • Instant comments
  • Direct communication
  • New features and apps suggestions
  • Early access to new apps and features

$200 /year

You can also support us by sending us a one-off payment using PayPal:

Leave a reply