ISS Solar Transit on May 1st, 2019

The ISS transits the Sun and a prominenceon 2015 August 21st.
Image Credit: Thierry Legault …

Save the date solar observers! On Wednesday morning, May 1st 2019, the International Space Station is predicted to make a three-star transit of the Sun around 09:40:00 am – the time will vary somewhat based on your location.

The transit should be visible for a narrow 6.2 km slice over the lower mainland ranging from Bowen Island and proceeding south-east over Maple Ridge. The Trottier Observatory at Simon Fraser University is located within 0.16 km of the center-line of that slice.

Warning: Protect your eyes when solar observing!

Never look directly at the Sun. Always use a proper solar filter specifically designed and approved for solar observation, available at astronomy stores; that meet the requirements for ISO Standard 12312-2:2015.

The web site is a fantastic resource to get predictions of ISS solar and lunar transits. Just select your location on a map it it will provide you with ISS transit predictions over the next 10 days.

The transit on May 1st only lasts 1.26 seconds so don’t blink. Also, the ISS is fairly small at 0.41 arc-minutes – about the same angular size as Jupiter – so you will likely need a telescope, with a proper solar filter, to spot it.

More details for observing from near the Trottier Observatory at SFU from the site:

★★★ Wednesday 2019-05-01 09:41:05.64 • Solar transit

ISS angular size: 41.22″; distance: 670.38 km
Angular separation: 0.6′; azimuth: 110.3°; altitude: 35.9°
Center line distance: 0.15 km; visibility path width: 6.19 km
Transit duration: 1.29 s; transit chord length: 31.7′

R.A.: 02h 34m; Dec: +15° 08′; parallactic angle: 36.3°
ISS velocity: 24.7 ′/s (angular); 4.81 km/s (transverse)
ISS velocity: 5.60 km/s (radial); 7.38 km/s (total);
Direction of motion relative to zenith: 176.0°
Sun angular size: 31.7′46.2 times larger than the ISS