Thursday, July 23, 2015

Simple Astro-photography's small adventure

Although astrophotography is a very professional disciplinary, it is also possible to create great pictures with simple equipment and proper techniques. It is mostly a matter to know your subject and what is suitable to our equipment. I already suggested a few simple astrophotography methods and it is time for more examples.

The timing was around the new moon even tough I didn't get too far from the urban area and the light pollution was high anyway. All the photos are without any post-processing (with the exception of crop). The main idea is to show what is possible before using nay software such as Photoshop or Lightroom in which the possibilities are endless. Personally I don't like post-processing. It can do wonders, it can do whatever you want if you know how, but sometime if a picture is too perfect it seems a bit fake. If I use software at all it is mostly to simple bright/contrast and level adjustments.

The first set is from Thursday 16/July/2015. The first shooting place was where a new bridge for the train gives some nice compositions. It was not planned but the big dipper just posed for a very nice image which may be a tribute to Red Hot Chili Peppers "Under the Bridge"


The big dipper
The big dipper

This is not related to astronomy but just gives a hint on the surrounding.
The bridges
The bridges



The next location was somewhat further away and inside a forest to eliminate some of the light pollution but the sky were still very polluted. In these photos I've used an Ioptron tracker to eliminate star trails. The tracker is quite new for me and  I still need to practice using it. I can't day that using a tracker is simple. most people will ot spend 300$ on such item which has a very limit purpose, but still it is an affordable and easy to setup. You can do without it for short exposures or for wide focal length. Most people use the 500 rule. divide 500 in your actual focal length (If your camera is a DSLR with cropping factor, don;t forget to calculate it as well), and this will give you the maximum exposure in seconds. usually you will need to use high ISO rate. So even for short exposure a tracker is suitable to use lower ISO value and maybe a closer aperture.

This is a close up of the open clusters M6 and M7. These photos requires a zoom lens so a tracker is almost a must (unless using really high > 3200 ISO). When taking such shots take first with a high ISO and without noise reduction just to be sure on your composition. Then use lower ISO and able noise reduction to get the best shot possible. 

open clusters M6 and M7
open clusters M6 and M7

This is part of Sagittarius with M22 and M8 visible in a wide-field photo. The area is rich with globular clusters but to get them a long focal length is required. I noted to myself to take several frames and stitch them together next time, using the longest zoom I have.

 part of Sagittarius
 part of Sagittarius 

And this is the entire Scorpion constellation. 

Scorpio
Scorpio


The next two photos are from July-18th. They were taken quickly from my roof just before the moon entered the clouds. It is a nice triangle of the moon Venus and Jupiter, and in the second photo Regulus of Leo is visible as well. These are quite simple photos with nothing but tripod. I didn't have the time to find nice compositions with terrestrial objects.


 The moon Venus and Jupiter and Regulus
 The moon Venus and Jupiter and Regulus

The moon Venus and Jupiter
The moon Venus and Jupiter


The last set is from Sunday July-19th from Tel-Hadid. In the first photo you can see me shooting the second sunset photo.


A photo of me taking the sunset photo below
A photo of me taking the sunset photo below

Sunset with Thorns
Sunset with Thorns
And two sunsets

Sunset
Sunset

Sunset
Sunset

The main object of the evening was to shoot a time-lapse of the new moon Venus and Jupiter. Here it is, 2700 photos taken over 90 minutes from 20:15 to 21:45 in just 45 seconds (120x faster). Enjoy!






Thursday, July 16, 2015

The best images from Cassini for 2015

With all the attention to New Horizons and Pluto lets not forget the veteran spaceship Cassini which makes wonders around Saturn and sometimes it seems as there is an artist photographer sitting there to get these great compositions.
Cassini is now on its 219's Rev around Saturn. The orbit is very elliptical and spans from about 200,000km to over 2,000,000km. Such an orbit is required to measure Saturn's gravitational field and also give chance to flybys around the moons. Each Rev is well planned in advance and is fully using the time to observe Saturn and the moons.
Here are some of the best photos of 2015
You can see many more at Cassini's website and I've added a link for each photo for more explanations and details in that website.
All photos are courtesy of NASA 

Lets start with an old photo which is not very familiar. This is a very known object from a completly different angel.

Southern pole of Jupiter:
Southern pole of Jupiter: Cassini. NASA
This is an old photo of Jupiter when Cassini passed near him in the previous decade. The angle is unique. Never before we saw Jupiter from down under! The great red spot and the entire clouds' bands are visible in this magnificent image.


What do you see in the following unreal picture? Obviously you see the ring but what is behind the ring? It is the ring shadow in Saturn surface! Cubist art in its best.
Modern art in Saturn's rings
Modern art in Saturn's rings
 This is moon Rhea. do I see that it also has a heart shape on it or is is my imagination?
Rhea
Rhea
 A flying sponge? That's what most people think of Hyperion
Hyperion
Hyperion
And Tethys looks just like the death star from star-wars (Me and the children are eagerly waiting for episode VII!)
Tethys
Tethys
Dione is beautifully aligned on Saturn ring which is extremely narrow in this photo. The dark silhouette of Saturn is a great background.
Dione
Dione
 Three moons in one shot and all of them thin crescent. hoe can that happen?
Titan Mimas and Rhea
Titan Mimas and Rhea
Who's who? The large object is Saturn! look carefully for the thin ring in the right middle. The small object is Titan which is a very large moon but small in front of giant Saturn.
Saturn and Titan
Saturn and Titan
 Janus and a tiny fraction of the rings below
Janus
Janus

Previous articles about Cassini and Saturn:


Monday, July 13, 2015

Pluto and New Horizons

New horizons is finally arriving distant Pluto. After almost ten years the flyby is just hours away early on July 14th 2015. The spaceship will neither land on Pluto nor orbit it, but will pass in a mere distance of 11,000KM from its surface giving us unprecedented details and information about it.
I am updating this post frequently both with new photos and images but also with historic information. Don't miss the chance to find Pluto yourself looking at two original images from the Lowell observatory

14/7/2015 - Today is the day
Want to be super updated?
Check NASA-TV and @NASANewHorizons on twitter
As expected NASA released a very good photo just before the PR. While new data will arrive only in about 12 hours after the flyby you can have a small taste with thie fine photo

Pluto from 76000Km. NASA
Pluto from 76000Km. NASA



Latest briefing from NASA (short 15-20 min Video, updated daily).


Recent update
13/7/2015 - Find Pluto yourself!!
This is Clyde Tombaugh who discovered Pluto in 1930 when he was 24 years old.
Clyde Tombaugh.
Clyde Tombaugh. Source: Lowell observatory
Finding Pluto was not easy and required to scan thousands of photographic plates to notice small differences. Although there were no airplanes or satellite it was a hard task. Today computers are doing it in seconds. Here are the two original photos. Clyde Tombaugh had a special instrument on which he could flipped two photos. and if he looked carefully enough he would see a difference. Most photos has no difference and even if they had, most of them were specks of dust. But eventually one was a new planet. You can try for yourself using the following two photos. Where is Pluto? (Click on the photo to see it bigger and easily change to the second photo. Try go back and forth between the two). Answers at the end of the article but do try to find yourself!
Where is Pluto 1 (Lowell Observatory)
Where is Pluto 1 (Lowell Observatory)

Where is Pluto 1 (Lowell Observatory)
Where is Pluto 2 (Lowell Observatory)
12/7/2015 - Why Pluto is not a planet anymore
The decision to move Pluto out of the planet's list is because several reasons:
1) Its orbits is very elongated  and inclined to the ecliptic
2) There are many small bodies like it in the Kuiper Belt
3) He is not big enough and is more to be considered as a binary system together with Charon
However the IAU (International Astronomical Union) had some hard time to define the exact rules in its 2006 conference. For further reading you can look at my review of Mike Brown's "How I killed Pluto" book.



13/7/2015 - Chasms on Charon
The newest photo of Charon is very interesting. A possible impact craters and a huge chasm relatively larger and deeper than the grand canyon.
כארון 11/7/2015
כארון 11/7/2015 - 4 מיליון קילומטטר. נאסא
What happens during the flyby?
The following info-graphic says it all. Many measurements with all the instruments on board. Just before the flyby a short transmission of the latest photos to Earth, probably for the PR section, and then 4 to 6 intensive hours of work, and only at the end a transmission of just a fraction of the data is planned. Want to see more? Check the eyes on NASA site
.



11/7/2015 
This 6Million KM photo of Pluto shows interesting feature. What is the Polygon?.
Pluto from 6 Million KM. NASA
Pluto from 6 Million KM. NASA
Here is more or less the same photo but from 4 Million km.
Pluto from 4 Million KM. NASA
Pluto from 4 Million KM. NASA

Pluto and Charon. NASA
Pluto and Charon. NASA

Here is an example of how demanding is the communicating task. The entire NASA's Goldstone station is communicating with New-Horizons. check yourself in DSN now. It changes during the day, but that is a good example.


כל תחנת גולדסטון מכוונת ל לחללית אופקים חדשים (NHPC)
All antennas at Goldstone are pointing toward New-Horizons


9/7/2015 - The heart of Pluto
We love these photos. We can imagine things, and this shape is called the heart of Pluto. does it look like a heart? Not really, but our mind tends to look or familiar features so even this approximation is enough. The "Heart" length is about 2000km and is probably new layers of frost gases such as Methane. The dark feature left to the heart is called "The whale". 

Pluto's heart. NASA
Pluto's heart. NASA

Would you think that it is a hear if you saw this photo first? I am not sure
Pluto's heart. NASA
Pluto's heart. NASA

The superb space blog - Universe Today gave a list of all not required things in the spaceship. usually objects to give some emotional aspect to the mission. Here is the summary from UT site (with permission)
  1. Some of the ashes of Clyde Tombaugh making him the human that reached the further away from earth,
  2. A CD with 430,00 names of people who registered at NASA site. I am not one of them, but this has become a routine so check out and list your name in future missions.
  3. Another CD with images of the entire mission's members.
  4. A quarter from Florida. If ET will need to call home.
  5. A flag of Maryland
  6. Two flags of the USA
  7. A small piece of Spaceship 1
  8. A stamp from 1991 with the caption: Pluto - not researched yet

The spaceship itself looks like a big piano. Here are two photos from two different angles


New Horizons. NASA
New Horizons. NASA

New Horizons. NASA
New Horizons. NASA

So where is Pluto? You will find it much easier in these photos
Pluto - the moving dot. Lowell observatory
Pluto - the moving dot. Lowell observatory

Pluto - the moving dot. Lowell observatory
Pluto - the moving dot. Lowell observatory
 

Thursday, July 9, 2015

Sundials stamps in Israel

During 2014 I had a unique experience - taking part in the design of a new series of stamps. I received a phone call from the Israeli postal service who contacted me after reading my article about sundials in Israel. Although I am not an academic expert on the matter, I gladly agreed to help.
As it turned out, issuing stamps is a serious matter. In Israel, the process requires a government decision, and after the decision is approved a long process begins. The first phase is to decide on a concept for the series, how may stamps there will be and what will be the connection between them. There are many sundials types and my original idea was to choose a sundial which was significant to the religion and used in a synagogue, a sundial to symbolize the value of hard work ("The day is short and the work is great") and a modern sundial which is more an element of design in an urban surrounding.
There were other suggestions and there were some political issues as well and the final decision was to show the development of the sundials over different periods and do this in only three stamps.
After that it was a hard task to decide which specific sundials to present. There are wonderful sundials which are not suitable for the format of a small stamp since it is impossible to see the small details and engravings, and this is also a factor. Following this, I worked with the stamps' designer, David Ben Hador. The designer wanted to include the sun in the stamp but when looking at a sundial the sun is usually behind the watcher, so there was no attempt to have the hour in the sundial match the sun position, but still our goal was to allow some freedom to the designer and maintain the best realistic sundial as possible.
After the design of the stamps there is a need to design the envelope, the leaflet, the first day postal stamp, choose a verse, write the text in the pamphlet and so on. This is the final and in my humble opinion, great, result (the values are from the last draft and are not the actual values of the stamps)



Sundials in Israel -Ancient Jewish Quarter Jerusalem
Sundials in Israel -Ancient Jewish Quarter Jerusalem

Sundials in Israel - Zoharei Chamma Synagogue Jerusalem
Sundials in Israel - Zoharei Chamma Synagogue Jerusalem

Sundials in Israel - Jezzar Mosque Acre
Sundials in Israel - Jezzar Mosque Acre

Sundials in Israel - day of issue envelope
Sundials in Israel - day of issue envelope