Look up tonight to catch Mars and ‘blood moon’ double bill

SINGAPORE — Look up at the sky in the wee hours of Saturday (July 28) to catch the longest "blood moon" eclipse this century, which coincides with planet Mars' closest approach to the Earth in 15 years.

The astronomical double bill — observable from Singapore — will kick off on Saturday at 1.14am with the partial lunar eclipse. The total eclipse — when the entirety of the moon is in the Earth's shadow — will occur between 3.30am and 5.13 am.

The lunar eclipse — the longest one observable from Singapore in recent memory — is happening alongside a Mars opposition — where the red planet will appear extra bright and large, as it is at its closest to Earth since 2003.

This eclipse will last 1 hour 43 minutes, only 4 minutes shy of the longest possible total lunar eclipse, according to US-based radio series EarthSky. This means, compared to January's eclipse which lasted only 1 hour 2 minutes, observers will have 41 minutes more to catch the natural phenomenon this time.

The last time a total lunar eclipse lasted nearly as long was on July 16, 2000, with a total duration of 1 hour and 46 minutes, according to the United States' National Aeronautics and Space Administration.

Saturday's moon, however, will appear smaller than January's as the eclipse is occurring during a micromoon, meaning the moon is at its furthest distance from the Earth, a Science Centre Singapore spokesperson explained. In contrast, January's eclipse took place during a supermoon, a phase when the moon was closest the Earth.

Just like January's eclipse, though, Saturday's moon will be a "blood moon", meaning it may appear reddish. This is due to the alignment of sun, Earth and moon, which allows the Earth's atmosphere to scatter blue light from the sun, while refracting or bending red light onto to moon, giving it a rosy blush.

The other visual treat for skygazers on Saturday is a bigger and brighter Mars, given its perihelic opposition — meaning the planet is at its closest to the Sun, and thus also the Earth, in its orbit.

Even though Mars opposition — when the red planet, the sun and the Earth are aligned — occurs every two years, perihelic oppositions are rare since Mars' orbit is not symmetrical.

The Science Centre spokesperson said in 2003, Mars came really close to Earth during its opposition, the closest it has been in 60,000 or so years. This weekend's opposition will be almost as close as that in 2003. The next time the record will be broken will be in the year 2287.

SPECIAL VIEWING SPOTS

Several viewing spots have been set up around the island for the astronomical double bill.

The Science Centre — in conjunction with the Lifelong Learning Institute (LLI) — is organising an overnight stargazing session on Friday evening held at the LLI. The event is fully subscribed, with organisers expecting some 120 adults and 80 children, aged seven to 12, to be in attendance.

Singapore Sidewalk Astronomy, a local community that holds stargazing events, will be setting up five telescopes beside McDonald's restaurant at Bishan-Ang Mo Kio Park from 10pm on Friday to 6am on Saturday, offering the public an opportunity to enjoy the rare celestial phenomena. The community spokesperson expects some 200 stargazers to turn up.

The Maritime and Port Authority of Singapore and the SingAstro stargazing community will also hold a public viewing at the Singapore Maritime Gallery (SMG), with about 500 expected to be in attendance. More than 12 telescopes will be available to the public for viewing at the roof garden of Marina South Pier. There will also be fringe activities, such as a tour of the SMG at 7.30pm and 9.30pm on Friday, and experts will share on practical astronomy and celestial navigation.

The next time a lunar eclipse will be visible in Singapore will be on May 26, 2021, according to Nasa.