In this video, we show you how to use the Hubble Legacy Archive (HLA) to gather raw image data of your favorite astronomical object.

Hope you guys enjoy it and if you have any questions feel free to post it in the comments.

Why does one image look better ?

Filters are very important in astronomical observation as they reduce glare and light scattering, increase contrast through
selective filtration, increase definition and resolution, reduce
irradiation and lessen eye fatigue.

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                                         Working of a magenta filter

Depending on which object you are looking, one chooses the appropriate filter. For instance the cover photo is without and withthe moon filter.

And on an amateur telescope they is how they are inserted.

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                                        Eye-piece filter (Source)

Telescopes like the Hubble have plenty of these filters stacked on them. You can find a list of the filters here.

Some popular filters commonly used are as follows:

Red –                           R

Green –                        V

Blue –                           B

Infrared –                      i’

Ultraviolet –                  u’

Hydrogen Alpha –       H-alpha

Oxygen III  –               OIII

LPR (Light Pollution Reduction)

Neutral Density filter  and so on…

Now here’s an image of the pillars of creation captured in various filters:

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Observe that the maximum number of stars are visible in the B, V and r’(infrared) filters. Therefore, combining these three image yields a standard image like the one you find online.

That being said, in our next post, we will run through a quick tutorial on how to access the Hubble archive and retrieve any image with any filter of your choice.

Have a good one!

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The Crab Pulsar (PSR B0531+21) is a relatively young neutron star. The
star is the central star in the Crab Nebula, a remnant of the supernova
SN 1054, which was widely observed on Earth in the year 1054.Discovered
in 1968, the pulsar was the first to be connected with a supernova
remnant.

The optical pulsar is roughly 20 km in diameter and the pulsar
“beams” rotate once every 33 milliseconds, or 30 times each second

The above video allows you to hear the signal from pulsar and the gif below that is the actual pulsar blinking taken with a high speed technique known as  Lucky Imaging .

Supernova Sorcerer: Robert Evans

fuckyeahphysica:

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                            Robert Evans with his reflecting telescope

Robert Evans is the world record holder for the most visual discoveries of Supernovae. Although he is a minister of the uniting church in Australia, he is better known in the Astronomy community as one of the ‘best Amateur Astronomers in the world.’

He is accredited for discovering 42 supernovas visually from his backyard!!

But, how on earth does he do it ?

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Having been looking at the cosmos for years on end, Evans has memorized the entire star field and the positions of the galaxies in the night sky.

And as a result of this, he can detect changes in the galaxy simply by looking at them through the telescope.

Why is this remarkable ?

This is truly remarkable for two pivotal reasons:

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A supernova is the explosion of a star. It is the largest explosion that takes place in space.

But spotting a supernova visually is extremely hard! 

To give a perspective on the intricacies of supernova hunting, here is a picture showing the night sky before and after a supernova in Messier-82.

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                                Supernova hunting in Messier-82

And secondly, he gave automated telescopes a run for their money. There are many telescope in recent times that automatically detect hundreds of supernovas every year.

But Evans managed to give them a tough fight in a battle against man and technology with his telescope sorcery.

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A note for budding astronomers

Why I find Evans to be extremely inspiring is because here is an amateur astronomer doing quality contributions to Astronomy in his backyard and with not so fancy equipment.

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Just shows how far passion and perseverance can take you in science.

Be limitless! Have a great day!

Yesterday’s post: Spectacular time-lapse from birth to death of a Supernova

Often times you look at really pretty images of Supernova remnants (what is left after a supernova explosion)
and are blown away by their magnificence. But the sad truth is that
there are not a lot of these supernovas that we can observe in such
great detail.

On the
bright side, in general there are lots of supernovas to observe in the
universe. And the above is a spectacular time-lapse of the Supernova SN 2015F illustrating how the Luminosity of a Supernova varies with time. 

More:

Star snapped before and after nova explosion-BBC

Supernovas and Supernova remnants – Images

This week on FYP! – Earth’s rotation

ICYMI we have been talking about Earth’s rotation for the past week on FYP!

We started off by asking the simple question: ‘Why did the Earth start spinning in the first place?

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And how has this rotation been affected by the moon over the course of centuries.

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But this did not give us any understanding for why the axis of rotation is inclined  by 23.5 degrees.

This is where we were introduced to the The Giant Impact Hypothesis which suggested that the Moon formed out of the debris left over from a collision between Earth and an astronomical body the size of Mars, approximately 4.5 billion years ago

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Now one of the consequences of living on a rotating object is that it flattens at its poles. The name given to such a flattened object is an oblate spheroid. We understood this using a simple experimental setup:

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Leaving all that aside, it was strongly believed by people for a really long time that it were the heavens that moved and not the earth.

It took a lot of debate among philosophers to come to the conclusion that it was indeed the Earth that was rotating. We looked at one such remarkable argument given by Galileo

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Having made this journey so far, we finally discussed how humans found a way to utilize the fact that we are on a rotating oblate spheroid to quench our thirst for the ecstatic understanding of the unknown.

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Gravitational waves, Light and Merging neutron stars

Unlike black hole mergers (gif-1), when two neutron stars merge (gif-2) they give off a huge blast of light in addition to the gravitational wave.

Today LIGO announced that they were able to detect the gravitational waves from the merger of two neutron stars and the revolutionary thing about this is that with the help of telescopes situated across the globe we were to able to confirm this.

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(Image credits: Left, Hubble/STScI; Right, 1M2H
Team/UC Santa Cruz & Carnegie Observatories/Ryan Foley)

These are indeed truly exciting times and there is no denying. Have a great day!

* Watch this video to know more

**  How LIGO detects gravitational waves

JunoCam : Processing | Mission Juno | Mission Juno

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                     A processed image of Jupiter from JunoCam

JunoCam
is a visible-light camera/telescope placed on the Juno Jupiter Orbiter.
But the cool part about this is that it was primarily put on board the
orbiter primarily for public science and outreach.

If you are
an amateur astronomer and also interested in image processing, you have
full access to all the raw images taken by the orbiter (check link).

Have fun!

JunoCam : Processing | Mission Juno
| Mission Juno

The war of the storms

Place: Jupiter

Years: 1997 – 2000

Summary: Around 1997, there were three great storms named FA, DE and BC on Jupiter. Then DE got jealous that BC was getting all the attention from Earthlings and went on a vortex attack ,destroyed it and ascended the throne as BE.

When FA came to know about what had happened, it summoned all the gases and went on a full out attack on BE to become BA

TL;DR:

DE + BC —> BE ;

BE + FA —> BA ;

( True story ! )