Aug 5: visible Falcon 9 upper stage impact on the Moon

[Dale Ghent]

Abstract:

On 2026 August 5, at approximately 06:35 UT, a spent Falcon 9 upper stage will impact the lunar
surface near Einstein Crater. This event will occur on sunlit terrain near the eastern limb as seen from
Earth. The impact flash and resultant ejecta plume from this event are potentially observable from
ground- and space-based observational facilities. This event provides an opportunity to attempt the
recording of an artificial impact in real-time; although many of the properties of the event (such as visual
magnitude) are imprecisely predicted at present. Moreover, this event provides an opportunity to test a
pipeline for localising impacts on the lunar surface for future seismic experiments, investigating the dust
and plume dynamics from impact events on the Moon, and considering hazards from artificial space
debris impacts. Both professional and amateur astronomers are encouraged to attempt observations
of this event.

Full paper:

https://arxiv.org/pdf/2607.14625v1

Anyone planning to be up for this? The Moon will be about 38 degrees up in the eastern sky when this impact is set to occur around 0235 EDT.

-Dale

[James Willinghan]

If the Moon is clear of the house behind mine I was planning to give it a try with my 12" scope. From what I read, it was not believed to be able to see the actual impact, but the dust plume might be possible against the blackness of space as the impact is near the edge and may last up to 10 minutes. Right now NOAA forecast says cloud coverage at 50%

James

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[Jason Goldstein]

Do we know how big of a telescope you will need to this see this?  Both visually and EA.   Will a S50 be able to catch it, what about an 8se?

[Dietmar Tietz]

This is what Google AI recommends for observing this event:

A small amateur telescope with an aperture as small as 10 centimeters (about 4 inches) is the minimum size required to potentially see the impact flash or debris plume. However, because the Falcon 9 upper stage is hitting a sunlit portion of the lunar surface near Einstein Crater, the event will be incredibly faint and difficult to distinguish from Earth. [1, 2, 3]

Essential Observing Guidelines

To maximize your chances of capturing the impact at 06:35 UTC on August 5, 2026, follow these requirements: [4, 5]

• The Telescope: While a 10 cm (4-inch) telescope is the bare minimum, astronomers emphasize that larger apertures are vastly better to gather enough light against the bright moon. [2, 3]
• High-Speed Camera: You cannot rely on your naked eye. You must equip your telescope with a camera capable of high-speed imaging at a minimum of 20 frames per second (FPS) so the fleeting flash is not lost between exposures. [2, 3, 4]
• Location: The timing highly favors observers in the eastern half of the United States, Canada, and much of South America, where the moon will be sufficiently high in the dark sky. [5, 6]
• What to Look For: You are looking for a brief pinpoint flash of light or a microscopic dust plume rising high enough to catch the sunlight against the darkness of space just beyond the moon's western limb. [4, 7]

If you are planning to observe this event, let me know your city or time zone and what specific telescope gear you currently own so I can help calculate the exact local time of impact and your visibility conditions!

Google link for follow-up questions: https://share.google/aimode/r4IVAhibMxQcIhbGj

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From: "Jason Goldstein" <jmg...@gmail.com>
To: "HAL Group" <howar...@googlegroups.com>
Sent: Friday, July 31, 2026 12:34:38 PM
Subject: Re: [howardastro] Aug 5: visible Falcon 9 upper stage impact on the Moon

To view this discussion visit https://groups.google.com/d/msgid/howardastro/cbfa8097-b429-4258-867e-459e402acbden%40googlegroups.com.

[David Illig]

I don't do much observing or photography anymore due to impaired vision (AMD). But, weather permitting, we'll find out if 4 in is the "bare minimum." I plan on using a 3.5-inch Questar duplex with a Canon EOS R5 Mark II, shooting video at 120 FPS. My Questar is a 1982 model, completely rebuilt with new optics at the Questar factory just prior to the 2017 solar eclipse. At the same time, my wife will be using a Seestar 50 under control of a 13-inch iPad.

Clear skies to all!