Mercury is best seen from 3.40 am to 4.30 am in the North East in the constellation Orion, later in Gemini. Venus is best seen from 9.30 pm to 11 pm in the West in the constellation Leo. Mars is too close to the Sun, only 7°. Jupiter is best seen from 9.50 pm to 11.10 pm in the West in the constellation Leo. Saturn is best seen from 10.35 pm to 2.15 am in the South in the constellation Libra.
Venus and Jupiter still form a nice pair in the evening skies. Both planets are slowly getting further away from each other. Venus is getting close to the bright star Regulus in Leo. Look towards the West in the early evenings.
The Moon is in Last Quarter on Wednesday 8 July, and is in New Moon on Thursday 16 July. The Sun rises at 4.50 am and sets at 9.32 pm. The days are again getting shorter. Make the most out of it!
Wednesday 08 July
At 9.24 pm it is Last Quarter Moon. This is the 2nd biggest last Quarter Moon of the year. The former larger last Quarter Moon was on 9 June 2015. The next larger Last Quarter Moon is at 26 July 2016.
During dusk, an Iridium flare appears in North North West at an altitude of 15° in the constellation of Auriga at 10.13 pm. Another flare at 10.56 pm in the West North West at an altitude of 17° in the constellation of Leo Minor. Not enough of flares? One more at 11.54 pm in the West South West at an altitude of 45° in the constellation of Bootes. And … after midnight at 3.06 am in the South East at altitude 50° in the constellation Pegasus.
Mercury rises at 3.41 am in the North East in the constellation of Gemini.
Thursday 09 July
Today in 1979 Voyager 2 passed Jupiter. This American interplanetary probe was launched in 1977.
ISS is crossing the Sun at 10.13 am. You will need a good and safe Solar Telescope or Telescope with good and safe Solar filter. You will see the big artificial satellite crossing the Sun’s disc from Tissington. Contact me if you need last minute calculations or information for your location. Do NOT look at the Sun without any special Solar filter! See picture I took earlier this year on 27 February.
At 10.07 pm, not so long after Sun set, an Iridium flare appears in the North North West at an altitude of 17° in the constellation Auriga. And one more at 10.59 pm in the West North West at altitude 15° in the constellation Leo Minor. And again at 11.08 pm in the West North West at altitude 13° in the constellation Leo Minor. After midnight at 1.24 am one more in the South South West at an altitude of 57° in the constellation of Sagitta.
Mercury rises at 3.44 am. Look North East in the constellation of Gemini before Sunrise.
Friday 10 July
Today in the year 28 a two and a half minute Solar Eclipse crossed South Western Ireland and Cornwall before the Sun set in France shortly afterwards. Also today in 1958 the first parking meters were installed in England.
Look at 11.12 pm towards West North West at an altitude of only 11° for an Iridium flare in the constellation Leo. Mercury rises in the North East in Gemini at 3.47 am. The Moon with earthshine is visible before Sun rise from 4 am onwards.
Saturday 11 July
At 1.33 pm the planet Mars is at its most far distance. The distance to Earth is 2.587 AU (Astronomical Units – 1 AU is the distance Sun – Earth). This is of course not noticeable as Mars is too close to the Sun to observe.
After midnight, on Sunday morning between 3.20 am and 3.30 am, the Moon is close to a few brighter stars in Taurus, called the Hyades cluster. All stars are to about 7 to 10 lunar diameter away. Try to look with a small telescope or best with a binocular. Aldebaran, the brighter star in Taurus is close to the Moon. Mercury rises in the North East at 3.50 am. Look for the Earthshine on the Moon at about 4.10 am.
Sunday 12 July
At 11.20 pm, the planet Venus is at its brilliancy and has a brightness of -4.69 magnitude. A kind of double flare is visible in the West South West at an altitude of 41° in the constellation of Bootes. The first one at 11.38 pm and the second flare at 11.39 pm. Worth to watch!
From about 1 am to 1.40 am it is best to see the Milky Way or the dimmer objects in the night sky. Mercury rises in the North East at 3.54 am, about an hour prior Sun rise.
Monday 13 July
Today in the year 158, it was the first total solar eclipse to have passed over London since 1 AD. It provided for them 1 minute of glory. Today in 2018 it will be the next solar eclipse on a Friday the 13 th. The last solar eclipse on a Friday 13 th was in December 1974. Both are partial solar eclipses. There are 24 solar eclipses on a Friday the 13 th between the years 0 and 3000. Of which 13 partial, 9 annular and 2 total solar eclipses. The most odd is the one of 13.03.313 which was an annular eclipse.
The nights are getting longer. To see dimmer objects such as the Milky Way, best time is after midnight between 0.40 am and 1.35 am. A flare appears at 2.45 am in the South East at an altitude of 54° in the constellation of Pegasus. At 3.59 am Mercury rises.
At about 4.40 am the Moon is visible as a Lunar Crescent only 45 hours before New Moon. The Moon is only 23° from the Sun and is 4% illuminated. The Moon rises at 3.48 am and 69 minutes before the Sun. A few minutes after, the Moon in maximum Libration East. Mare Crisium limb on the Moon is tipped into the Earth’s view.
Tuesday 14 July
Pluto flyby by New Horizons – see special about Pluto. NASA's New Horizons will pass Pluto and Charon today. We will then see eclipses of the Sun by first Pluto and then Charon, looking for signs of atmospheres way out there. See http://pluto.jhuapl.edu/overview/ScienceShorts.php?page=ScienceShorts_11_26_2014
Today in 2013 the world's last telegram was sent in India. It was the last major country to shut down telegram service. India's 163-year-old telegram service was no longer needed, as e-mail and texting had replaced bicycle telegram messengers. In Great Britain the telegram delivery ceased in 2008, while the US was terminated 27 January 2006. The first formal telegram was sent by Samuel Morse in Washington to his business partner Alfred Vail in Baltimore on 24 May 1844.
On Wednesday morning, a flare appears at 1.02 am in the South South West at altitude 55° in the constellation Hercules. Mercury rises in the North East at 4.04 am.
Wednesday 15 July
After Sun rise, at 5 am the Moon is close to Mercury. Not visible as it is daylight. The limb separation is 6° or 12 lunar diameters.
A bright flare visible at 11.29 pm West at altitude 36° in the constellation Bootes. New Moon after midnight at 2.24 am. The International Space Station (ISS) is back and appears at twilight at 3.53 am in the South at 4°, culmination or highest point is at 3.56 am in the South East at only 10°. ISS disappears at 4.00 am. Mercury rises at 4.09 am.
Get in touch with me via www.patrickpoitevin.weebly.com if you need more information.
Not Pluto from Disney, but the planet … dwarf planet Pluto will be visited
New Horizons is passing Pluto and Charon Tuesday 14 July.
Pluto, named after the Greek god of the underworld, was discovered on 18 February 1930 by Clyde W. Tombough at Lowell Observatory. Pluto is the second closest dwarf planet to the Sun and was at one point classified as the ninth planet in our Solar system. Pluto is also the second most massive dwarf planet with Eris being the most massive. Its mass is 0.00218 times that of the Earth or 13 050 000 000 000 billion kg. The diameter is 1480 miles or 2368 km and the orbit distance is 367 125 000 miles or 5 874 000 000 km, which is 39.26 AU. One Astronomical Unit is the distance Sun – Earth. The orbit period is 246.04 Earth years; the surface temperature -229°C and so far we know Pluto has 5 Moons: Charon, Nix, Hydra, Kerberos and Styx.
No spacecraft have visited Pluto before. Though now, on 14 July 2015 the spacecraft New Horizons, which was launched in 2006, is scheduled to fly by Pluto on its way to the Kuiper Belt in our Solar System. As the New Horizons spacecraft gathers information about Pluto before and after its July 2015 close encounter, practically every day we are learning more about this dwarf planet. We will be able to understand much more about its atmosphere, its Moons and how it fits into the story of the Solar System’s history.
Some other facts?
Pluto was reclassified from a planet to a dwarf planet in 2006. The IAU (International Astronomical Union) formalized the definition of a planet as “A planet is a celestial body that
a. Is in orbit around the Sun
b. Has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape
c. Has cleared the neighborhood around its orbit”
It took 76 years between Pluto being discovered and the time it was reclassified as a dwarf planet, which made Pluto completing a third of its orbit around the Sun.
Pluto’s Moons are Charon (discovered in 1978), Hydra and Nix (both discovered in 2005), Kerberos originally P4 (discovered in 2011) and Styx originally P5 (discovered in 2012) official designations S/2011 (134340) 1 and S/2012 (134340) 1.
Pluto may be the largest dwarf planet. Or it could be Eris? Currently the most accurate measurements give Eris an average diameter of 1454 miles or 2326 km with a margin of error of 7.5 miles or 12 km, while Pluto’s diameter is 1480 miles or 2368 km with a 12.5 miles or 20 km margin of error, however due to Pluto’s atmosphere it is difficult to say for certain.
Pluto is one third water. This is in the form of water ice which is more than 3 times as much water as in all the Earth’s oceans. The remaining two thirds are rock.
Pluto is smaller than a number of Moons in our Solar System. The lager Moons are Ganymede, Titan, Callisto, Io, Europa, Triton, and our own Earth’s Moon. Pluto has 66% of the diameter of the Earth’s Moon and 18% of its mass.
Pluto has an eccentric and inclined orbit. This takes it between 2.75 and 4.63 billion miles or between 4.4 and 7.4 billion km from the Sun meaning Pluto is periodically closer to the Sun than Neptune.
Pluto’s location was predicted by Percival Lowell in 1915. The prediction came from deviations he initially observed in 1905 in the orbits of Uranus and Neptune.
Pluto has an atmosphere (sometimes?). During Pluto’s elliptical, when Pluto is closer to the Sun, its surface ice thaws and forms a thin atmosphere primarily of nitrogen with a little methane and carbon monoxide. When Pluto travels away from the Sun the atmosphere then freezes back to its solid state.
Pluto consists of rock with a very thick coating of ice. The atmosphere of Pluto consists of nitrogen with some carbon monoxide and methane.
Eris is the most massive dwarf planet and is also the furthest from the Sun. The mass is 16 700 000 000 000 billion kg. Eris has one notable Moon called Dysnomia.
What could we learn from the New Horizons flyby?
The principal investigator for New Horizons, Alan Stern, does not agree with the definition of “dwarf planet”. Will Pluto remain with this status or will it be upgraded to a “Planet” again? Even if so, the IAU will revisit only in 2018 – until then we have to wait if Pluto will be classified as a planet again.
We knew for decades about Pluto’s Moon Charon. The two are so close in size that some people considered the system a double planet. How does this fit with the dwarf planet designation? And what about the other 4 Moons?
Strange but true that Charon could have an ocean given it is so far away from the Sun. The tidal force imparted by Pluto’s gravity early in Charon’s history could have stretched the Moon’s insides and warmed them up enough to create liquid.
As with our own Moon, some believe Charon was created after a large object smashed into Pluto billions of years ago. This would have created a chain of debris circling the dwarf planet.
Pluto is a tiny world, but like the Moon and Mercury it does have a very tenuous atmosphere that is called an “exosphere”. Astronomers first spotted signs of it in 1985.
Astronomers think Pluto looks a lot like Neptune’s Moon Triton. Triton and Pluto have very different histories. Triton was likely captured by Neptune long ago. But Pluto and Triton likely do have some similarities. Like the frozen volatiles (elements with low boiling points), the faint nitrogen atmospheres, and their similar composition of ice and rock.
Pluto could have a ring system. A research team suggests that debris floating around Pluto could coalesce into a faint ring system.
One day it will be all revealed …