The Sky This Month, July

Back-to Back Eclipses, Meteor Showers and More!

Nakshatra NITT
Nakshatra, NIT Trichy
7 min readJul 1, 2018

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Man has always found answers to his question of existence while looking up to the overwhelming universe. Every aspect of the society has been influenced by the cosmos. Let’s start with a small story:

Sherlock Holmes and Dr Watson decide to go on a camping trip. After dinner and a bottle of wine, they lay down for the night, and slept. Some hours later, Holmes awoke and nudged his faithful friend.

“Watson, look up at the sky and tell me what you see.” Watson replied, “I see millions of stars.”

“What does that tell you?”

Watson pondered for a minute.

“Astronomically, it tells me that there are millions of galaxies and potentially billions of planets.”

“Astrologically, I observe that Saturn is in Leo.”

“Horologically, I deduce that the time is approximately a quarter past three.”

“Theologically, I can see that God is all-powerful and that we are small and insignificant.”

“Meteorologically, I suspect that we will have a beautiful day tomorrow.”

“What does it tell you, Holmes?”

Holmes was silent for a minute. Then spoke: “Watson, you idiot. Someone has stolen our tent!”

We are all either Holmes or Watson. We all have our own reasons to lose ourselves in the vastness of our universe. Whether it’s a child marveling at the twinkling of stars or a scientist observing the path of comets, the universe has something for all of us. It’s easy to get lost with so much happening every night in the heavens.

So here we are to give you a little guide to this month’s celestial explorations. As Carl Sagan said, “Somewhere, something incredible is waiting to be known.”

Starting with the 6th of July, on this day, the Earth will be at the farthest position from the Sun in its elliptical orbit, in other words, at its ‘aphelion’.

Ever wondered how we have summers when we are farthest from the Sun? That’s because of the tilt of Earth’s axis which is at 23.5 degrees, which plays a greater role in determining seasons than the distance between Earth and Sun. For the record, the distance between the two this year at aphelion is going to be a whopping 152,095,566 km (you can try calculating the torque involved, it’s huge!).

Fan of eclipses?

The wonderful sight of a solar eclipse awaits us on the 13th of July. But since it happens almost entirely over water in the Southern Hemisphere, a partial eclipse will be observable only on the southern coasts of Australia and New Zealand. Alas!

(Picture Courtesy: pixabay.com)

Take a break for a day now, as the stunning sight of the crescent moon with the dazzling evening star Venus awaits us on the 15th. Both of them can easily be spotted in the southwestern sky after local sunset within a separation of 1.6 degrees. Another thing to watch out on this day is the earthshine- the pale glow in the unlit part of the crescent moon.

Now how does this happen? When there is a full moon, the light from the Moon illuminates the Earth’s surface, right? Now, imagine the opposite. You are standing on the Moon’s surface and you will see a full Earth from there, whenever there is crescent moon visible from Earth. So now, the full Earth will illuminate the Moon’s landscape and thus this light is reflected and comes back to us earthlings. So, it is twice reflected light- once from Earth’s surface to the Moon and then back to Earth.

(Image Courtesy: openphoto.net)

Mid-July phenomena are mostly shy to our naked eyes or home telescopes, but the end of the month holds quite a few spectacular tricks to display. First up is the Red Planet which reaches its opposition on the 27th of July, hence appearing the brightest since 2003. Now to break down terms, the opposition is nothing but the position when Earth, Mars and the Sun all three of them are in a straight line. Since such a linear arrangement is a rare occasion (Because both the planets are in their respective elliptical orbits around the Sun), this is a special event you should clearly not miss. So, enjoy the breathtaking view of the Martian polar caps and the dark volcanic plains with your telescopes as Mars winds up with its closest approach at 7:50 am on July 31st with a distance of a meagre 35.8 million miles. So you may as well gear up to watch the sky that is going to be illuminated by a super bright orange celestial body in the last week of July!

The night sky of 27th July will be dark, only to be illuminated by the faint rusty glow of the Blood Moon. For those of you who missed the Blood Moon of January 31, here’s your chance to witness the Moon go dark on the evening of July 27, when a total lunar eclipse will be visible from South America, Europe, Australia, Africa, and Asia.

Engulfing the sky in darkness for a whopping 1 hour 43 minutes, the total eclipse will be followed before and after by a partial eclipse lasting for 3 hours and 55 minutes, making it the longest lunar eclipse of the 21st century. On the same day, we will witness the smallest and furthest full moon of the year as the Moon reaches its apogee, that is, it’s the farthest distance from Earth.

Curious about the term ‘Blood Moon’?

Here’s an insight into the origin of the term. The term ‘Blood Moon’ has both religious and scientific origins. Scientifically, the word ‘blood’ signifies the deep red or reddish brown colour of moon during eclipses. Such a phenomenon is observed due to sunlight travelling through Earth’s atmosphere which then bends around the edge of our planet and falls onto the Moon’s surface. Another major reason here is the scattering of short wavelengths by the Earth’s atmosphere leaving behind the red end of the spectrum.

When is the best time to view this spectacular reddish glow?

The time of greatest eclipse will be 8:21 pm (GMT) on July 27. The total eclipse will last from 8:30 p.m. to 9:13 p.m. (GMT).

Just as any stargazer wishes, imagine yourself lying on a soft patch of grass and admiring the heavens above. Suddenly, you spot a bright streak that comes and goes literally in a flash. You’ve just seen a ‘shooting star’, and it’s time to make a wish — maybe for another one that’s even brighter!

Awestruck by this majestic phenomenon, you feel that maybe there’s a chance that your wish will come true, because what’s more pacifying than gazing at the fireballs up from a dark location, far from city lights. The bright yet brief streaks from meteors can catch your eye just at the limit of visibility or can be dramatically bright fireballs that appear brighter than Venus and light up the nightscape around you.

This July, get ready to feast your eyes on the brilliance of the night sky illuminated by these natural fireworks. July 28–29 is all set to witness the beautiful Delta Aquarid meteor shower.

But wait, what are meteor showers and where do they originate from?

It so happens that when Earth crosses the orbital path of a comet, which on coming near the Sun, warms up and sheds bits and pieces. This comet debris spreads out and slams into the Earth’s upper atmosphere at about 90,000 miles per hour, vaporizing — burning up — as meteors or shooting stars.

(Picture Courtesy: flickr.com)

The July meteor shower or Delta Aquarids is said to have originated from the breakup of what are now the Marsden and Kracht sungrazing comets. An interesting fact about the origin of the shower’s name is that Delta ‘Aquarid’ gets its name from the constellation Aquarius as the meteors radiate from it in the sky.

However, here’s the catch you must know about before getting ready to witness this event: The full moon on July 27 might obscure the brightness of the shower. But fret not, you might be able to catch a glimpse of the dazzling lights in the sky around 2–3 a.m. on July 29.

That’s all for this month’s updates on the cosmos. Get your calendars marked for all the events, ’cause everything in this universe is worth watching. Have fun with the stars!

This article was written by Nakshatra members Himanshi Gupta and Ishani Srivastava. Poster by Pavan Bhushan.

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Nakshatra NITT
Nakshatra, NIT Trichy

A student-run university-wide organization for sparking awareness and fascination in astronomy. Interested contributors can contact us by email.