Amazing facts about Jupiter

Jupiter is the largest planet in the solar system, a gas giant of Hydrogen and Helium with some Ammonia in the upper beautiful clouds layer (and small amounts of other things). Juno spacecraft will arrive to Jupiter on the symbolic day of the 240th independence day of the USA and enter into an orbit around it. Here are some interesting facts about Jupiter.

Jupiter - Hubble telescope - NASA

Jupiter is massive

Jupiter is not only big, it is massive as well. You can say that the entire mass of the solar system is divided in the following way. 99% of the mass is the Sun, 2/3% of the mass belongs to Jupiter and all the rest is just 1/3% (This division is not scientifically accurate but is suitable enough for our needs). Jupiter mass is two times the mass of everything else in the solar system except the sun, and this mass influences the sun and cause it to wobble a little in its orbit. The barycenter of the sun-Jupiter system is well OUTSIDE the sun. 

Jupiter can't become a star

Although Jupiter is huge it is still far too little to become a star and it requires to add at least twenty times its own mass or even more to become so. Adding just little more mass, two-three times as its current mass, will not make Jupiter bigger but will make it denser, but not dense enough to start nuclear fission. 

You can see Jupiter in daylight

Jupiter is seen clearly from Earth. It is the brightest object in the sky after the sun, moon and Venus. Under best conditions, Jupiter can be seen during the day. It requires some practice but possible.

Jupiter has lots of visitors

The first spacecrafts to visit Jupiter were the Pioneer missions in the early seventies followed by both Voyagers missions in 1979. It took some time for the next visitor, Ulysses in 1992 which was on her way to explore the sun poles and got to Jupiter in order to use its gravity to change orbit. Galileo in 1995 was the first spacecraft to orbit Jupiter for a long period and ended in a brave crash into its atmosphere. Cassini just said a quick hello in 2000 on her way to Saturn and New-Horizons also "stopped by" for a cup of coffee on her way to Pluto. Juno mission will be an interesting long mission around Jupiter.

Jupiter protects us

The great mass of Jupiter helps to keep the solar system clean and remove hazards such as asteroids and comets from the inner solar system. Sometimes Jupiter fell asleep during his watch and the dinosaurs are still angry about him, but without Jupiter, things will be worse. Jupiter also gets the bullet for us from time to time. In 1994 Shoemaker-Levy comet crashed into Jupiter and left some scars on it for about a year. Not long ago an amateur astronomer got another small crash on video:

Jupiter is not alone

Jupiter has lots of company. 67 moons so far and probably plenty of smaller ones. Its four largest moons were discovered in 1609 by Galileo. The largest moons - Io, Europa, Ganymede, and Callisto - are bright enough to be seen by the naked eye, but Jupiter is too close to them and prevents that. Even a small binoculars will show the moons.

It is best to keep some distance from Jupiter

Ask Io. A small moon and one that its planet has enormous influenza on its structure. Io is smaller than our moon and the distance from Jupiter's center to Io is around 400,000 km. To be so close to Jupiter is not a good idea. Strong gravitational forces cause earthquakes and volcanic activity and made Io look like... Like what actually?

Io - Nasa JPL

Jupiter helped to measure the speed of light

The Danish astronomer Ole Romer noticed a difference between the predicted time and actual time of Io's (The cheese ball from above) eclipses behind Jupiter. His idea was that these difference derived from the changes in Earth-Jupiter distance and that the light has a speed. He gave a value of 220,000km/sec which is around 76% of the actual value, a really good approximation!

Jupiter can suddenly Vanish from our view

Well, not that suddenly but the moon can occult Jupiter (just like any other planet). It is a rare event and here is a short video I took several years ago.

Moon and Jupiter conjunction

A conjunction between the moon and any planet is a monthly event. Not rare but always a pleasure. This post will be updated with photos and reports about Jupiter and moon conjunctions:

2016-03-22: The moon  is further away from Jupiter but rose just below it giving a chance for interesting compositions:

 The moon and Jupiter 22/3/16

The moon and Jupiter 22/3/16

The moon and Jupiter 22/3/16

The moon and Jupiter 22/3/16
Can you see my shadow?

2016-Mar-21
There was a not-so-close conjunction.

I first saw (and photoed) Jupiter about 10 minutes before sunset (17:45 15:45 UT), the distance to the moon was about 5 degrees:

The moon 17:45

The moon and faint Jupiter (Bottom left)

And two other photos from 21:00 am (1900 UT) the distance is shorter, just 4 degree. The moon is the same but the background is completely black adding more contrast

The moon 21:00

 This photo is a single exposure. Jupiter is big enouch and bright enough to seen as a small disc with a yellow/orange color (You might need to enlarge the photo). As you can see I manage to capture both of them at the maximum zoom possible.

The moon and faint Jupiter (Bottom left)

The pair will get closer during the night.

2016-01-27
Less than 2 degrees

2016-01-27 - Moon and Jupiter

Jupiter and Venus Conjunction

One of the most interesting events coming in 2015's summer will be the conjunction of Venus and Jupiter. These two bright planets can already be seen clearly in the west just after sunset. Venus is brighter and lower than Jupiter, and they get closer every day!
These planets are the brightest objects in the sky except for the sun and the moon. A conjunction between them is not rare, but such a close encounter does not happen very often. Here are links to photos from the 2012 conjunction 2012 and from the 2008 conjunction.

New photos!
New photos from the event itself 30/06/2015
I started in daylight and here are the two. Jupiter is a small orange ball and Venus shape is visible. The camera was Canon HS SX50.

Daylight Venus and Jupiter 30/06/2015

The next two photos showing Venus and Jupiter through a telescope. It was amazing to see them both in the same field of view. Jupiter with its strips and moons and the thin crescent of Venus. In the photograph however, I had to choose the exposure. A long exposure to get Jupiter's moons and a short exposure to get the shape of the crescent. So I took two

Venus and Jupiter through a telescope 30/06/2015

Venus and Jupiter through a telescope 30/06/2015

 OK, Saturn is always beautiful so why not take a photo of him as well?

Saturn

I invited friends to see the wonders of the sky. Many arrived to see the conjunction, Saturn, and the almost full moon. What a splendid evening!!!

These photos are from June 29 2015! Enjoy and scroll down to see the difference of just one day!

Venus and Jupiter 29/6/2015

You can clearly see Jupiter's moons in this photo!

Venus and Jupiter 29/6/2015

Venus and Jupiter 29/6/2015

Venus and Jupiter 29/6/2015

Venus and Jupiter 29/6/2015

Venus and Jupiter 29/6/2015

And notice the difference in just one day

Jupiter and Venus 28/6/2015

Jupiter and Venus 28/6/2015

Jupiter and Venus are the brightest planets, and way back in the past, on June 17th, 2 BC, their conjunction made them so close together, just 40 arc-seconds apart, that they seemed as a single, very bright star, which might be the origin of the "Star of Bethlehem" (although there are other astronomical theories for this star, such as a Supernova, a comet or other conjunctions). Look at the Illustration below. An observer looking through his telescope at a 100x magnification, would have seen this incredible sight. Venus is closer to Jupiter than Jupiter's moons and is just a little bit smaller than Jupiter. Jupiter's angular size is 32" and Venus's is only 25". This is indeed a sight not often seen! An even more spectacular conjunction will be on 22-Nov-2065, when Venus will actually go in front of Jupiter, obscuring a little part of it. Unfortunately, Jupiter and Venus will be only 7 degrees from the Sun so the chances to see it are near to zero. The next occultation will be in 2123, a bit too far in the future for most of us.

Venus and Jupiter conjunction 2 BC illustration

The current conjunction will not be as close as that of 2BC and the planets will be seen as two, but very close to each other. The first event to notice is on 13/6 when Venus will pass near the Beehive cluster (M44). Even a small binoculars will suffice to see it. The next interesting event will be on 20/6/2015 when the new moon will join the pair to create a triple conjunction.

The moon, Venus and Jupiter 20-Jun-2015

The moon, Venus and Jupiter 20-Jun-2015

And a short (17sec) time lapse of 18 minutes

Here is my own photo of Venus and M44 taken from a really light polluted area and yet, the cluster is visible

Venus and M44

Look at the illustration below. The little cloud below Venus is M44 and it also demonstrates how fast Venus moves.

Venus,Jupiter, the moon and M44 20/6/2015 Illustration

The nearest conjunction will be 10 days later on 30/6 with a distance of a third of a degree (22 arc-minutes). This is less than the diameter of the moon. If you have a telescope, you can use a magnification in which you can still see the entire moon and include both planets in the same field of view. If you don't have a telescope don't worry! Many people will photograph the pair and beautiful pictures are expected.
One day later (July 1st, 2015) the distance will be greater, but still less than half a degree. The distance will increase with every passing day as the pair will continue to move, each in its own celestial orbit.

Updated photos 18-Jun-2015!

New moon Venus and Jupiter 18/6/2015

New moon Venus and Jupiter 18/6/2015

Venus Jupiter and Leo constellation

Venus Jupiter and Leo constellation

Here are two photos taken three weeks apart which show how the distance is getting smaller.

Jupiter Venus and the moon 21/5/2015

Jupiter Venus and the moon 9/6/2015

The following song was a big hit in Israel and you will enjoy it even without understanding the words. Its name is "Milky way Ballad " and here is my freestyle translation for it.

Milky way Ballad
Venus send a smile to Jupiter

Hey Jupiter, lets go out

A cappuccino cup in the Milky way

And drop by Cassiopeia

Grab the dipper, little or big

This night is terrific

It's quite a bit, Jupiter and Venus alone

Going out hand in hand 

hand in hand in the heavens...

Lets jump for an hour to the north star

With a light breeze blowing

Just don't be like Plato

Those I do not like

Without a notice, on the tail of a comet,

we will sit for a moment

It's quite a bit...

Jupiter and Venus going higher

The stars wink to them

And Orion said without doubts

What a couple

And only Mars become jealousy red

She will leave him soon in the future...

Jupiter Venus and Mercury

An interesting stellar conjunction is about to happen, starting from 20th of may until the 27th of May 2013. Jupiter, Venus and Mercury will be close to each other in the west, immediately after sunset.
Conjunction between two planets are very common and even between three planets are not rare. Conjunction are always a nice sight to watch and no equipment is needed. Look here for photos of a previous conjunction between Jupiter and Venus and try to think of a great photographs opportunists near your house.


This is what you will see on May 21st. Mercury is only 5 degrees above the horizon and Jupiter is 13. Jupiter is going down and down and Venus and Mercury up. Watch for several nights to see how the planets move.

Jupiter Venus and Mercury May 21st 2013

And here is a real photo from 22-May-2013. Jupiter is in the top, Venus and Mercury in the bottom.

Jupiter Venus and Mercury 22-May-2013

This is the planets position on May 26yh. Mercury is now the highest of the planets.

Jupiter Venus and Mercury May 21st 2013

And a real photo taken by my dear wife Rosalind Eidelheit. As you can see, Rosalind was very lucky to find some seconds with all three planets visible with these many clouds!

Jupiter Venus and Mercury May 26th 2013

And just one day after. Much less clouds!

Jupiter Venus and Mercury May 27th 2013

And another one from the 28th. I like the power lines which look like a musical score - a celestial symphony

Jupiter Venus and Mercury May 28th 2013

Jupiter will continue to go down until it will disappear from the evening sky and become a morning start, while Venus is about to dominate them for the coming months.

Seeing Jupiter in daylight

Until recently  I thought that the only planet visible in daylight is Venus. Although I was able to track Jupiter some minutes after sunrise, I didn't think it is possible to see it an hour or even more before sunset/after sunrise. However, reading this article in EarthSky proved me wrong and I immediately tried to carry out the suggested observation. Some notes and tips:

1. You really need to use the moon as a guide to locate Jupiter. Jupiter is very dim and locating it with nothing to mark its whereabouts in the sky is extremely hard. Also it is easy to focus on the moon and then search for Jupiter.
2. It is best to view Jupiter when it is 3 months behind/before the sun so when the sun is low, Jupiter is high in the sky (the angle between the sun and Jupiter is about 90 degrees).
3. Although the article mentions that the best conditions occur once in 12 years, you should try and observe Jupiter in daylight even in not the greatest of conditions and at least once a year.

In my case It was easy to spot the moon and I was surprised to find Jupiter quite easily. Here are some quick snaps.

The moon in daylight

 You will need to enlarge the next photo. Jupiter is in the bottom right corner.

The moon and Jupiter in daylight

Jupiter occultation summary

Jupiter occultation stood up to my expectations. I didn't set up anything in advance due to the weather, I just got all the equipment ready and outside the house. I set up the alarm clock for 3am and tried to get in a few ours of sleep. When the alarm went off, I went out to see the moon which just rose in the north-east. Even with the naked eye the view was fascinating, and Jupiter was very near to the edge of the moon. I set up everything and then Venus rose as well. Venus showed a lovely crescent phase! Then all there was to do was to take pictures and wait. The weather was clear but humidity was very high. I used two telescopes: one for viewing (a small refractor with x100 magnification) and another one for photos and video (Bresser N130 with Philips SPC 900 Webcam).

The following pictures show the first part the disappearance. It happened so quickly that you can easily miss it. I just pressed the button to take the video and moved to the other telescope for visual observation. It took around 80 seconds and it seemed just like the moon swallowed Jupiter.

Jupiter occultation

And the video (I was some seconds too late to start it, sorry)

But don't worry, it came back after an hour, you might even see the famous earth shine

Jupiter occultation

And as dawn arrived I took a photo of the general view of the sky with the moon, Jupiter and Venus just before sunrise. I followed Jupiter to see how long after sunrise I could see it with the naked eye. Since it was so close to the moon it was relatively easy to see it even 25 minutes AFTER sunrise.

The moon Jupiter and Venus (bottom) after the occultation

And another bonus was that at 5:40am I saw the live launch of Soyuz for the ISS over the internet.

Jupiter Occultation

An occultation is an event in which a celestial body covers another, farther away object.  Usually, the term is used to describe an event when the moon covers a star or a planet or when a planet or an asteroid covers a far away star. On July 15th there will be a marvelous Jupiter occultation. The moon will cover Jupiter for about an hour (the exact time and durtaion of the occultation is  dependent on the observer's location).

Occultations can also contribute to science. During the 80s Uranos occulated a distant star. Photos of the events showed that just before and after the occultation the star blinked several times. The theory was that Uranus has a set of rings (like Saturn). When Voyager 2 reached Uranus it detected and photographed the predicted rings.

Seeing Jupiter's occultation is possible with the naked eye, but the look through a telescope, even using a small magnification, is marvelous. At first, two of Jupiter's large moons (Io and Europa) will disappear behind the moon, then Jupiter will disappear and then the other two moons (Ganymede and Callisto). It is best to check your local almanch for the exact times. The times given here are appropriate for Israel. Unfortunately the event will not be seen in the United States at all, but US observers will have a Venus occultation in August!

Here are some tips for occultation observations:

1. Start early - Even the view of Jupiter so close to the moon is great so start watching it as soon as possible (Which will be when the moon and Jupiter rise in the morning)
2. Check the weather - If weather is bad its worthwhile to drive off to somewhere else. Check with other astronomers in different cities nearby
3. The occultation itself is very very short - a few seconds only, so make sure you know exactly when it happens.
4. If you have two telescope use both. If you want to try and photograph as well you might need help. It is difficult to handle both at the same time and you might need to choose between visual observation or astrophotography
5. Check out when the end of the occultation occurs. You will need to be very accurate for this, and you can divide your attention between visual and photography to the start and end of the occultation
6. Do not forget the moons! Watch carefully until all moons are occulted.

Jupiter occultation times for Israel (GMT+3)
Date: July 15th (The night between Saturday and Sunday)
Occultation start: 4:03
Occultation end: 5:06

Jupiter Occultation - Illustration

Venus and Jupiter Conjuction part 2

As I wrote in Venus and Jupiter Conjunction, today, Mar 13th is the date that Venus and Jupiter are in the same height in the sky. Their actual conjunction will be between the 14th and the 15th of March, but the alignment was a great opportunity to take some great photos.

I've started with a photo from my roof. It is OK, but there is no proper background unless you call the solar water heating system a nice background.

Venus and Jupiter conjunction still in daylight

So when my wife came home, I could go and wonder on the streets finding proper angles which will add to the atmosphere. First of all I will thank my dear wife for letting me go out in the busy early evening hours. Here are the results:

The first photo is from the parking and shows the next building. This is already getting better

Venus and Jupiter conjunction

After that I've found some trees for the background, this one looks a but like a monster's face.

Venus and Jupiter conjunction looking like a face

And this one above a high palm tree

Venus and Jupiter conjunction and the tall palm tree

After that I went to the old water tower. water tower is a new word in English I learned today!

Venus and Jupiter conjunction and the old water tower

 And above it from further away.

Venus and Jupiter conjunction and the old water tower

 Are you familiar with the Jewish holiday of Hanukkah? If not, here is the explanation briefly. During Hanukkah it is a tradition to light candles in the Menorah. Many public building has an electric Menorah which operate only through the eight days of Hanukkah (The middle light, the Shamash is additional candle). Any day, one more candle is lit. Anyway This is the first Astro Menorah with Venus and Jupiter being the candles.

Venus and Jupiter conjunction Astro Menorah

 Venus is located properly but Jupiter is off a bit. Couldn't get to the proper angles as I have no wings.

Venus and Jupiter conjunction Astro Menorah

 And the last photo is an overall look. Notice the orange tint. The air is full with dust and Jupiter was hardly seen even high in the sky. Time to go home.

Venus and Jupiter conjunction