April Astronomy Highlights – it's a Busy Month in the Skies

Monday 7 April 2014, 3:37PM

By Stardome Observatory


April is a month packed with notable astronomy events – so mark these dates in your diary!

Anniversary of First Human in Space
On April 12, 1961 Russian cosmonaut Yuri Gagarin was the first human to make the daring journey into outer space. On this day he bravely completed an orbit of the earth in the Vostok 3KA spacecraft achieving the celebrated status as the first human to enter outer space and the first orbital flight of a manned vehicle. Stardome is celebrating this important day in space flight (NASA launched Space Shuttle Columbia on the same date in 1981), named International Day of Human Space Flight and Yuri’s Night by screening a special planetarium show about the Google Lunar XPRIZE, Back To The Moon For Good and a presentation on Gagarin. Learn more about the man and the adventure!

David Britten, Astronomy Educator at Stardome says “It is interesting that the first man in outer space was selected based on his ancestry, and stature - there was no room in the space craft for someone of large build. Gagarin orbited earth once, which took just 108 minutes but his legacy of adventure and bravery is still celebrated today.”

Mars Up Close
Just a couple of days later on April 14, Mars – our nearest, potentially habitable planet – will be at closest approach, giving Earth dwellers an opportunity to view the red planet in extra detail.

In 2014 Mars reaches opposition on 8 April as Earth overtakes it in its orbit, although it is actually closest to Earth six days later on 14 April, putting Mars just 93 million kilometres away. While it will be even closer in 2018, this is the closest to Earth it has been since 2003. The term ‘at opposition’ means that the object (in this case, Mars) Earth and the Sun are 180 degrees apart on the sky, so the object rises as the Sun sets.

The best time for viewing Mars through a telescope is in April, after which it will get significantly smaller as Earth leaves it behind. To the naked eye, Mars will be very bright and noticeably reddish in colour. Through a good telescope, you may see distinctive dark markings. While these markings have been noted for centuries, it is only in the last 40 years, since the Mariner 4 expedition, that the markings have been understood as sporadic global dust storms and seasonal changes in polar ice coverage.

David Britten, Astronomy Educator at Stardome, says “Although tiny Mars is at its closest, a clear view even with a good sized telescope can be rather difficult. A steady tripod is essential, and you need to be patient and wait for the local cloud and atmospheric conditions to settle. The surface is clear at present, but there could be a massive Martian dust storm that clouds the atmosphere and blocks the view of the entire surface for months. Keep your fingers crossed for favourable Mars and Earth weather conditions!”

Lunar Eclipse
April 15 brings the first of two lunar eclipses for 2014. This eclipse will be special because it starts soon after the sun sets and from a high vantage point looking east you will be able to see the Moon rise from 6.00pm and move within the Earth’s shadow to be completely eclipsed by 7.08pm. This marks the start of totality and at this time the Moon will be 15 degrees above a flat horizon – less if there are hills. Maximum eclipse is at 7.46pm and totality ends at 8.23pm at which point the Moon will be 30 degrees above the eastern horizon. The Moon will be completely out of the umbra by 9.32pm. It will look a bit dim because it will still be within the penumbral shadow until 10.36pm, when the eclipse finally ends.

This eclipse occurs close to the horizon so a high, clear vantage point will be necessary to view. It’s an exciting prequel to the midnight eclipse later in the year.

David Britten, Astronomy Educator at Stardome, says “Watching the Full Moon rising darker and darker – rather than the usual large bright disc – will feel quite strange. To see the Moon disappear during the eclipse all you need is a good view of the eastern horizon.”