Venus within a degree of Aldebaran

Event Date: July 9th
Time: 5:00 AM


Brief

   Venus has its best pairing of the year with star Aldebaran this morning.  Before showing the pair in telescopic view, I will remind that Venus is still binocular-friendly with Jupiter for the next week.  Currently, the two are about 5 1/2º apart, and best seen in a field of about 7º; to see Jupiter's Moons clearly, this size will work.  Venus' thin crescent shape will not be noticed at such a low magnification, although it has become brighter fast over the last two weeks.  As the planet reaches greatest brilliancy later this month and best apparent magnitude about the same time of the summer, I will bring both to attention.
   Getting back to Aldebaran, it is labeled along with Venus 0.9º apart.  The first image shows both bright planets and Aldebaran zoomed out-while the second shows Aldebaran and Venus alone in a field of 1.4º.  For that one, the software shows Venus dimmer, yet zoomed in enough to someone see the crescent shape.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   Showing above in the second image, closer to Venus than Aldebaran, are 6th and 7th magnitude stars, at 14 and 26 arc-minutes apart from Venus respectively.  Although those separations are impressive when using a higher magnification, which also lets us see Venus' crescent larger, the stars are quite dull in comparison to brighter, orange-red Aldebaran.
   After this close encounter with Aldebaran, Venus parts ways from the giant star for about 10 more months.  As a result of its change of motion against the stars, Venus has spent a few weeks in the Hyades, having close encounters with other stars visible with the unaided eye.  If you have used optical aid to view it during this time, you may have noticed Venus come very close to some dimmer stars as well.  The next time that Venus visits Aldebaran and the Hyades in May of 2013, it will happen when all are in the glare of the Sun, and not visible.  We will have to wait until late June of 2014, and Venus will only pass the Hyades rather than "cut through" it.

galactic center transit before midnight

Event Date: July 8th

Time: 11:44(.43) PM


Brief

Back on July 4th, as witnessed from our longitude of 122º 10' 54", the galactic center transited the [azimuth] meridian just after midnight by seconds; the closest that it does to the "0-hour" for the calendar year.  Interestingly enough, as people shoot off the last of 4th of July fireworks before the holiday is over (legally or illegally!), this transit occurs.  As seen in the image below, we see the triple-intersection of the three lines.  I showed this meeting of the three, a couple of months ago when it happened in the early morning hours.  Just as the stars rise almost four minutes earlier each day, as will this transit.  In about two more months, it will happen during evening twilight, happening about four hours earlier than this evening.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   As the image also shows, the ecliptic (green) passes about six degrees north of where the galactic equator crosses the galactic meridian (g.m.); this line is that perpendicular to the Milky Way, with its billions of stars slightly brighter to emphasize.  As a result of the Sun always passing precisely at that spot on the g.m., it means that the Sun will never meet the point of intersection of the two purple lines, marking the galactic center.  There, is also a black hole.  As I mentioned back in mid-May, any adversity or disaster that happens December 21st 2012 will not be astronomically related as a result of the black hole.
   Sagittarius and Scorpious are the two featured constellations here in stick-figure form.  As seen from mid-northern latitudes, they are seen low in the sky at transit time.  The Sun passes the brighter stars of Scorpious during the end of November and much of December, while passing Sagittarius' between the December solstice through mid January.

Venus leaving Jupiter, nearing Aldebaran

Event Date: July 7th
Time: 5:00 AM

Brief

   Venus continues to slowly pull away from Jupiter, although the latter's pro-grade motion is still fast enough to almost keep up with Venus and show them at precisely the same separation.  Every morning however, while now past conjunction with the Sun, Jupiter is gradually slowing down in pro-grade motion and Venus is quickly increasing in that direction against the stars.  Here they are featured below, with Venus still in the Hyades star cluster and the Pleiades star cluster northwest of them.  Just southeast of Venus is a bright star which it passed once already in retrograde, and about to pass by closer this time in prograde: Aldebaran.  The bright star Capella which I featured yesterday within its parent-constellation Auriga, is shown further north to the left.

Detailed

    The separation between the two planets was a little less than 5º about a week ago, and now a little over 5º.  They will remain binocular-friendly as a pair for about one more week, and a few days longer if your binoculars give a wide field up to 10º.
   Now that the Sun is rising slightly later each morning, with that rate of change increasing more quickly as this month progresses, the problem of long twilight will eventually go away as well.  As it is, the planets, stars and clusters mentioned so far here, are more visible low to the horizon than they were a couple of weeks ago.  As we zoom in to Venus and Aldebaran within the Hyades cluster (which Aldebaran is not a part of, remember), we can see how the planet is coming closer to the star in separation angle.  This morning seen in nautical twilight, the two are seen 1.2º apart.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

We will come back to the pair in two days, and look at them at their closest.  For either day, they are a good binocular pair, while a telescope can include them too this morning when a wide field is used.  Use a field of 2º for this evening, which may require an eyepiece with a large apparent field of view, and/or a low f-ratio of between 5-7.

Auriga and its stars, including Capella

Event Date: July 6th
Time: 5:00 AM


Brief

   I talked about Capella for much of the spring, before it disappeared into the glare of the Sun.  Even a week or two before that happened, it was already visible in the morning.  Capella is a favorite star among pro and amateur viewers, because of its brightness: it flashes orange-ish red and green when high enough above the horizon yet still affected by atmospheric pollution.  When seen at its lowest in the sky from latitudes north of about 49º (the western US/Canadian border), it is seen a solid, light red.  Although the software doesn't let me show these fancy changes of color as a result of light refraction, I can still show Capella at an altitude that also lets us see the other stars making up its parent constellation: Auriga. 
Here is Capella and Auriga labeled below, with Venus, Jupiter and the Taurus star clusters seen to the right (south-southeast) of it.

Detailed

   At a declination halfway between the north celestial pole and equator, it is one of a few bright, recognizable stars which can be seen for a small number of weeks during both the morning and evening of a day; Vega and Deneb are two others, although the latter is dimmer than both Vega and Capella.  Many other stars in constellations such as Perseus and Hercules have stars that also can be seen after Sunset and before Sunrise.  These constellations and their stars are not circumpolar as seen from our latitude, yet far enough north for this to happen. 
   As mentioned earlier in the year, there is a star, El Nath, that makes up the stick figure of Auriga, yet not part of the constellation any longer.  Refer to what I said about that here.  As a result, I didn't label El Nath, belonging to Taurus only.  As for the Charioteer, which Auriga represents as a man holding a goat, they are not alone in this section of the sky: looking carefully when zoomed in for the following image, where there are three dim stars (labeled) next to diamond-shaped Auriga.  They form an acute angle.  This asterism is called the Kids (i.e. young goats, not young children!)  With a goat as part of the Auriga constellation, this is very fitting, as the stars are dimmer in comparison to the four that make up the Charioteer's stick figure.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Venus and Jupiter: altitude/azimuth comparisons

Event Date: July 5th
Time: 5:30 AM/11:51 AM


Brief

   Let's stick with Jupiter and Venus for one more day.  We will continue with what I talked about yesterday with same azimuths.  Whereas yesterday I showed the alt/az grid, today I will show the celestial grid to show the different declinations of Venus, Jupiter and the Pleiades.  Venus and Jupiter have moved slightly east from where they were yesterday, and also slightly further separated from yesterday; that separation rate will grow during upcoming weeks, as Venus starts to pick up speed in pro-grade motion.  For today, as the time above shows, I display the planets and Pleiades higher.  Eventually in the sky after Sunrise, Venus and Jupiter are no where close to the same azimuth in comparison to the showing of yesterday.  However, as I show them in image two during the daylight hours, they eventually reach the same altitude.
   Image one shows them during civil twilight, while image two shows them during daylight.  With a telescope or even binoculars, both are findable in the daytime if you known exactly where to look on a very clear day. 

Detailed

Notice also in image one, that Aldebaran and Venus are once again close together.  During the end of its retrograde, Venus pulled away from the star after passing it.  Now, with the "curve" that we see Venus make since those last days and past stationary, the two will have a closer encounter as Venus passes it in pro-grade.
   For image two, the planets are shown high in the sky.  Although neither is as high as a summer solstice Sun, Jupiter is almost as high as the Sun, currently being just past the June solstice.  Venus is losing ecliptic latitude quickly and declination while separating more from the Sun.  It is not quite as high as Jupiter, yet still appears about the same at transit later in the day.

planets and clusters rise in darker sky

Event Date: July 4th
Time: 4:19(.56) AM

Brief

   Venus and Jupiter are now easily visible in the morning sky during nautical twilight, although they are already both high enough during the middle of astronomical twilight.  If you are either a night-owl or a very early bird, look towards the east-northeast at the time above.  If obstruction is minimal, brighter Venus is seen below Jupiter with a separation of 4.9º  As Venus begins its prograde motion with Jupiter still moving slowly in that direction, they stay at the same separation for a few days, and within binocular view of each other for several days.  As I showed last week, Venus has been visiting the Hyades star cluster since late last month. and for the first week or so of this one.  Above Jupiter is the Pleiades star cluster, which unarguably gets more attention than any other open cluster with its "Little Dipper" appearance; I talked about last month while it was starting to rise in the morning.  Here are both planets and clusters shown together, in image one.  They are unlabeled to see more clearly, low to the horizon.

Detailed

For the above image and the one to follow below, we see Jupiter and Venus at exactly the same azimuth, which is why I selected the above time: 72.2º  The Pleiades is just slightly to the right of these two, at azimuth 72.5º.  There is some coincidence to this alignment, given the different declinations of each planet: the Pleiades is a little further north of Jupiter which is north of Venus.  I will show the altitude/azimuth grid, with the celestial figures zoomed in.  By zooming, we see that Jupiter and Venus are the same separation from the line closest to it, and the Pleiades is almost the same separation.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.
Time: 4:19(.56) click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

   For a fun viewing project, watch Venus, Jupiter and the Pleiades as soon as Venus is visible above the horizon.   Do you notice the change in azimuth between then, as shown for this entry, and several minutes later?  What about altitude?  Tomorrow, I will show them an hour later and show that difference.

Saturn and Mars' celestial paths

Event Date: July 3rd
Time: 9:00 PM


Brief

   Saturn has been in binocular view of Spica for nearly a year; back and forth in prograde and retrograde has let us see them between from 8º to under 5º apart.  This range of separation suits most types of binoculars, giving us two very different types of planets to observe: one is covered with rust and about 1/18th the diameter of the gaseous other with spectacular rings.  Of course, Saturn's rings are barely visible with even the most powerful of binoculars.  Using a small telescope with a magnification of 80x lets us see them well, while a more powerful telescope lets us see them much more clearly.
This evening, we come back to the pair of planets, with Mars catching up with Saturn.  When we last "checked in" with them, Mars was over 30º apart.  Now with both in the constellation of Virgo, Mars faster motion in pro-grade has it within 23º apart.  Watch Mars close in further over the next five weeks, with celestial paths seen here.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   Above in the image via their paths, we see Saturn just beginning to increase in pro-grade motion after reaching stationary a little over a week ago.  We also see how it has become closer and further from Spica during the retrograde, although the difference in separation has hardly been noticeable through binoculars.  Mars' path displays the last days of retrograde and then several days of prograde.  The 10-day increment markers spread out as Mars picks up pro-grade rate.
   After the August closest encounter between the two, as a reminder, Mars separates from Saturn much faster, eventually moving only slightly slower than the Sun west to east against the stars by the time of its conjunction with our star late next winter.  It will not revisit Saturn again until almost exactly two years after this upcoming August conjunction with the ringed, gas giant.  By that time, the two meet in the next constellation that Saturn visits after Virgo: Libra, which Saturn enters September 1st of next year, at precisely 12:15 local time (19:15 GMT).

how to find the Summer Triangle's center

Event Date: July 2nd
Time: 2:07(.59) AM


Brief

   Yesterday, I glazed over the transit of the Summer Triangle; listing the time and showing it.  However, it is not obvious why the Triangle's transit time is what it is, given that none of the stars are at transit at the same time.  Altair is close, yet not exactly the same as the "center" of the triangle.
To find the center, we have to think geometrically; remember that in high school or college?? ;-)  Oddly enough, after using the tools on the software to find out where to find the center of the Triangle, it helped me remember a little from those days.  Before getting into the detail, here is one more showing of it at transit with both the alt/az grid and meridian included.  I marked zenith also to show the relative positioning of each star.

Detailed

   First of all to quickly clarify, the time above shows the transit time of the Triangle's center.  Now, what do we do to identify that?
*If a perfectly straight line is drawn from each of the Triangle's stars, regardless of whether it or any other triangle is equilateral, isosceles or any other shape, that same line when bisecting the side opposite leads to all three lines meeting at a common point.* 
When setting the Triangle at a transit time one evening, I tried this, and it was true, meaning that the software engineers did well!  That is really all there is too it.  With other asterisms not so simply geometric (the Big Dipper for example) it may be much more complicated than that to identify its center.  We will look more into other asterisms' centers some other time.  Using the Summer Triangle is to simply point out that all constellations, asterisms, deep-sky objects, etc. all have transit times.  For most of them, it is when they reach their maximum altitude, as the case of the Summer Triangle's center.  As for the stars of the Triangle during the center's transit, Vega does so about 1 hour, 5 minutes earlier; Deneb almost exactly 1 hour later (a little over 59 minutes); Altair just a little less than 9 minutes later.  Use the grid in the image as reference for each, with the altitude ones circling outward from zenith.
   There is another way to roughly identify the center, now that we know the transit times of each star before and after the center's, seen from mid-northern latitudes: using Altair and seeing it about as high as it will go, we have a good idea of when the center transits even if we were not to know the geometry procedure mentioned earlier.  At different latitudes of course, the transit time differences of each will be different, and the Triangle will not even be seen the same when looking directly south or north, as far as which star is considered the apex; that is alright though.  Spend the next several weeks enjoying the star high up, and for the rest of this month, seeing it high enough above the horizon all night along. Albeit it a short night being summer for our hemisphere, it is still a decent number of hours! 
As a final note, the altitude of the center of the Triangle at transit is 83.9º as seen from out exact latitude.  Therefore, using the image above, look at where the 85º altitude marker is, between the r for summer and T for triangle.  At the tip of the r's "stick-out" and slightly below the hard-to-see 84º marker, is the 83.9º mark the center, almost exactly.  Neat?
  
   This second image is a zoom-in to show it a little more clearly, and the Triangle filling up the whole field.  Try this with your telescope sometime, if you have an alt-az one carefully marked and calibrated (be level to the ground too) and tell your astronomy buddies that you are looking at the center of the Triangle!  Of course, once you find it, chart the star field so it is a little easier to identify in the future.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Summer Triangle: rising, transit, setting

Event Date: July 1st
Time: 9:30 PM/2:11(.55), 5:00 AM (see NOTE*)


Brief

  I have taken a long break from the Summer Triangle with all the recent planet talk.  Now, as we begin the second half of the 2012 calendar and deep enough into the summer season, the Summer triangle gets alot of evening attention.  All three stars rise before Sunset, with Vega rising the earliest about 4:30 PM (local).  Deneb rises a little over an hour earlier with Altair doing so shortly before Sunset.  With all three stars north of the celestial equator and our Sun below the horizon for only about 10 hours, we see these stars still well above the horizon just before morning twilight washes them out at about 5:30 the next morning.
  *NOTE: The three images that I will show below are *out of order time-wise, yet still in sequence: early evening when the Triangle is visible on the rise, late night hours when it transits, and the aforementioned 5:30 AM time for when we still see the stars fading in the west.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   As I have shown repeatedly for morning journals of the Triangle, Vega and Deneb transit very high, with Vega (nearly) at zenith when it does, seen from mid-northern latitudes.  Deneb is a little further from zenith at transit for our latitude here at almost 38º N, yet hardly noticeably given its excellent declination.  Altair arcs high in the south, being 30º south of Vega and about 38º south of Deneb.  Therefore, as image 3 shows, Altair is lowest to the horizon and first to set after the Sun comes up. This will be more noticable in August and September, when I show the Triangle lower towards the west and northwest horizon.
Look as a reminder, how the celestial grid reminds us of the declination differences, particularly of Altair.

Mercury and Gemini stars setting

Event Date: June 30th
Time: 9:00 PM


Brief

   Mercury at greatest elongation this evening, has had its best days to be viewed with the eye alone now behind us-- earlier this month that is.  We will end the month with it difficult to see with the eye alone, at magnitude +0.5.  By the time that the Sun is low enough that its glare is not so intense, Mercury is already starting to be deep in atmospheric pollution.  Try binoculars on it, which definitely helps.  If using a telescope, it is already past dichotomy at 40% illuminated.  Aphelion is about two weeks ahead of us, leading to the lower magnitude for greatest elongation.  That is, if compared to the -0.3 that we saw it for such in March; between  +0.1 and -0.1 being an average range.  In March, it was closer to perihelion and reflecting a little more light to our eyes.
Here is the planet seen in orbit, with the celestial guidelines as well.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   Despite the only-fair showing of the planet for this elongation, the approaching of aphelion means that it is 7º further separated from the Sun than it was in March.  One other small advantage of it moving away from the Sun as it approaches inferior conjunction, is that it is slightly closer to us, and appears slightly larger in a telescope with high magnification.  That angular diameter change is hardly noticeable, and especially when not high in altitude when finally visible.  A powerful telescope using high magnification can distinguish the difference in diameter.
   Try finding Mercury as soon as the Sun's glare allows over the next few days when using a telescope, during evenings when the further failing of the western sky's geometry will not be affecting the finding of it.  If waiting until a week from now and days to follow, not only does Mercury continue to dramatically dim; retrograde motion begins and it starts to fall faster towards the Sun's glare.  This evening, it sets 92 minutes after the Sun, and easily visible to the eye for only about 20-30 of those minutes (skies permitting) before sinking too low.
   Finally, as we watch Mercury sink, so do the same for dimmer stars Castor and Pollux to its right (north, labeled above).  These two require optical aid to see well after the Sun goes down, and will not be easily visible again until late July/early August in the morning sky.

Venus' visit with Hyades' stars

Event Date: June 29th
Time: 5:00 AM

Brief

   Yesterday, I showed Venus "visiting" stars in the Hyades star cluster, which is nothing new: it does this occasionally when it reaches this part of the sky, since the cluster is just a little south of the ecliptic.  This year is a little unusual, however as a result of Venus finishing retrograde while within the Hyades.  Because of this, it means that we get to see it within the cluster for several days, and close to several stars visible to the unaided eye.
  The first image shows Venus' orbit, which "swung" it as many as 7º north of the ecliptic in the late winter, to about 4º south of it this week.  Jupiter is labeled also, with the planets only a day from their peak of conjunction July 1st: 4.8º for that day.

Detailed

   Unfortunately, after Venus leaves the cluster during pro-grade, we don't see it in this part of the sky again for about another two years.  It does get close to the Hyades in about 10 months, yet at that time, the Sun will be in the way and Venus only past superior conjunction by a few weeks.  The next time to easily see Venus near the cluster, for when it will not be as close, yet still a good pairing, will be almost exactly two years from now: June 27-30, 2014.
   Bringing ourselves back to 2012, here is one more look at Venus within the cluster.  The second image shows the planet and cluster's stars, using a binocular field of view, at 9ª.  At 16' arc-minutes from Venus this morning, 4.8 magnitude star Delta2 Tauri, is the star closest to Venus.  It will likely require binoculars to easily see both together, considering with the eye alone, Venus' glare will make it very hard to see Delta2, even with a very dark sky.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Venus, Jupiter and star clusters

Event Date: June 28th
Time: 5:00 AM

Brief

   Let's take a look to see how that Venus/Jupiter pairing is doing: the separation between the two has come to a peak of 4.9º, which is 1.9º more than the 3.0º they had on March 13th.  Despite that, and being seen lower towards the horizon, they are still an excellent sight.  At 17% illuminated, Venus is closing in on its best magnitude again (currently -4.4).  It was only less than two months ago when we last saw it at this crescent phase setting after the Sun.  Now that it is rising before the Sun, we are seeing Venus go through the phases in the opposite direction.  Jupiter (-2.0) also slowly brightens a little more each day as we catch up with it in orbit, yet not noticeably.  We will see a more obvious increase for Jupiter this fall when it nears and reaches opposition,

The first image is a zoom-out of the two during the middle of nautical twilight.  The Sun doesn't rise for about another 50 minutes following the time shown.  Even when it does, try to spot the planets for a brief time while the sky is still of a low limiting magnitude; this changes as the Sun gets higher, making it more difficult to see both about 30 minutes later.  Brighter Venus is at the bottom.

Detailed

   The next image is a zoom-in of the same planets, about 5x magnified.  This is like looking at them in small binoculars, which are more ideal for the other two neat targets close to each.  Venus actually, is seen among one of them: the Hyades Star Cluster, forming a "V" shape turned sideways when seen rising from our latitude, has its stars surrounding Venus.  It is a very open, wide-field cluster, including several stars visible to the eye in darker skies.  One of them labeled here however, Aldebaran, is not part of the cluster, as its brighter magnitude indicates.  Also, see the Pleiades cluster above Jupiter, now easier to see further separated from the Sun.  Venus is seen very close to a star in the Hyades: Delta1 Tauri (Hyadum II) is the star, seen at magnitude +3.4.  Venus is close enough to the star to see both in a wide-field telescope.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Uranus in...Cetus(!?)

Event Date: May 11th, June 27th*
Time: 7:51(.23) PM (image 1)/4:00 AM (image 2)*


Brief

  Back on May 11th at the precise local time above, Uranus did something rare for its orbit around the Sun: it moved temporarily into a non-zodiacal constellation, being Cetus, the Sea Monster.  South of Pisces and made up of mostly dim stars, Cetus gets high enough in the sky to see during hours sandwiching transit time, yet requires a dark sky to see most of them.  For now, that doesn't matter; what does, is (1) where Uranus is, (2) why exactly this happens, and (3) how long will it be there.  Before I get into that in the detailed section, *let's back the calendar up to May 11th to see exactly when Uranus crossed the Pisces/Cetus border. 
NOTE: As a result of a very busy month, I completely missed this until yesterday, when I talked about it and Uranus' position in the sky briefly. 
  The image is a zoom-in of 5x.  This way, we see the boundary near the ecliptic and Uranus' orbit a little more clearly than if zoomed out all the way.  We still see part of both constellations' stick figures even.  The sky is darkened and the horizon hidden to show the detail with no light or obstruction.

Detailed

   If we look at where Uranus' orbit is above, only a small portion of it is within Cetus' boundaries, which carve out a decently large portion of sky to fit the creature.  The ecliptic just barely misses it, which is why we never read about the Sun crossing into Cetus.  Theoretically, it does for a very small amount of time, since the ecliptic gets as close as 5 arc-minutes from the boundary and the Sun is 30 arc-minutes in diameter.  Therefore, as much as one-third of the Sun's diameter and a small chunk of its area from our perspective, is in Cetus.  This happens early in the spring, yet goes unnoticed by many new astronomers who are taught of the Sun crossing the brighter stars of twelve zodiacal signs;  okay, actually 13 if you want to count Ophiuchus' foot, yet we'll get into that later this year when it happens...a little too complicated to elaborate on for now!
As for Cetus, now look below for an image for today's date, and see where Uranus is; soon to leave Cetus and back to Pisces just days from now.  It will move into Cetus, for which I will mention the day when it happens, with retrograde briefly later this year.  Then, comes prograde one more time in early 2013.  It will not return to Cetus again until it gets to this part of the sky again for its next revolution, about 84 years from now.  Therefore, if you want to say that you saw Uranus in Cetus and in your 20's or younger, this year and next may be your next years-worth of months to do so! 
This second image is zoomed-in as well at 5x. I changed the clock back to yesterday's time, when showing Uranus and Neptune.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Uranus & Neptune: higher and zoomed

Event Date: June 26th
Time: 4:00 AM


Brief

   It has been over a month since I last showed Uranus and Neptune in the morning sky.  Now that the Sun is starting to rise slightly later each morning and at a faster rate, that means that it will be easier to see the distant planets.  They are rising about four minutes earlier each evening, and well placed in dark enough skies to see them easily with a telescope.  With Uranus, binoculars will do fine for locating it, although using a 'scope helps identify the slowly changing star patterns near it when using a small field (1º or less).
   Before elaborating on the fields for each planet, here they are zoomed out.  At the time listed above, the Sun is just starting astronomical twilight, so the sky is still dark enough to see both.

Detailed

  Now, for the fields: first for Neptune in western Aquarius, followed by Uranus in Cetus near the Pisces border.  *Yes, I know that Cetus is not a zodiacal constellation, yet Uranus' orbit "briefly" puts it there!  More on that tomorrow. 
The fields for both will be 1º, which doesn't help show color of each easily, yet shows enough stars to help recognize some patterns.  With their slow movement against the stars, Uranus spends and average of 12 weeks near each [circle] degree of stars, while slower Neptune spends about 6 weeks for each.  How did I find these numbers out??  Easy.  Uranus takes 84 years to go around the Sun.  If converting that to weeks 52.1 weeks per year while adding 21 leap years (84 divide by 4=21, then divide by 7=3), we  get about 4,380 weeks.  This, divided by 360º in ecliptic longitude, equals a little over 12.  Since Neptune take slightly less than twice as long to go around the Sun, that is how I got the 6.  Neat???
Anyway, enough of the math.  Here are the star fields.  Remember the patterns to easily find each.  With 1º of field, that is a magnification range of 50-55x with most eye pieces.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

early summer moon positioning

Event Date: June 25th
Time: 8:30 PM


Brief

As we view the Moon nearing first quarter this evening, with the Sun setting at almost its latest of the year, our satellite is seen several degrees further south.  At 2º south of the celestial equator and the Sun at 23º north, it means that the Moon's time above the horizon is only for another three hours, 42 minutes elapsed from the time above.  By comparison, when we looked at the same phase of Moon in late January and February (40%), it was setting closer to 5 hours after the Sun.  It was at that time north of the Sun by several degrees, closer to where the Sun is now.  During the summer and fall seasons, the Moon and planets seen just east of the Sun and setting after it, will be seen south as the ecliptic indicates in the image.  Notice the smaller angle that it forms with the horizon, while the Moon's orbit also has it almost midway between the nodes (not shown).  We know this from seeing the trough-like appearance of the orbit.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

  
Detailed

   As the Moon reaches first quarter and continues to wax, it will start to come back to the next node and go north of the ecliptic shortly before becoming full.  By then, as mentioned a few days ago, it will be much further south on the celestial dome, where the Sun is in the late fall and early winter. 
   The cycle of the Moon in the sky may seem confusing, yet the easiest way to remember where to find it, is being aware of its elongation from the Sun and recalling what season we are in: during summer, the Sun is at or near its furthest north, near its furthest south during winter, and about midway at the time of the equinoxes.  With that in mind, can you always remember where the Moon is for each phase?

Jupiter, Venus and Aldebaran "get together"

Event Date: June 24th
Time: 5:30 AM

Brief

   Now that Venus and Jupiter are becoming more visible in the east-northeast sky before Sunrise, we will soon see other stars near them.  One of those, I mentioned about a week ago near Venus, has spent a binocular separation with the planet over the last week: Aldebaran, as the brightest star in Taurus the Bull.  Here they are zoomed-out, with Jupiter also shown.  As the giant planet is 5.5º from Venus and Aldebaran is 3.0º from Venus, the three fit in a 9º field.  While both Venus and Aldebaran start coming closer to each other, and Jupiter starts moving closer to both, the field will shrink to fit them all.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

    With Venus first passing Aldebaran in retrograde and soon to do so closer in pro-grade next month, the pair will be an impressive viewing with the eyes alone, and with optical aid,  Venus' motion in retrograde and pro-grade near Aldebaran makes the separation pattern between the two a little more confusing than it may appear.  That is, since it will reach stationary further from Aldebaran than it is now and then come much closer quickly as Aldebaran rises four minutes earlier each day, it gives us a chance to follow Venus' celestial path on a morning-by-morning basis.  I will not show the path yet; see if you can visualize it for every clear sky you see with Venus.  Hopefully there will be little or no overcast; even if so, Venus is bright enough too see through high, thin clouds.  Try to find it with binoculars if too cloudy to see easily with the eyes alone.  Keeping Aldebaran in mind with its altitude and the same time each morning, try drawing Venus' celestial path in mid-July, after it has another close encounter with the star.  Good luck and enjoy the challenge!

Mars approaching Saturn and nearby stars

Event Date: June 23rd
Time: 9:30 PM

Brief

   After a bit of a layoff from Mars and Saturn, let's take a look at the "red" approaching the "ringed", regarding separation.  When I last talked about them, Mars was near the Leo-Virgo border, and has finally left the Lion's celestial territory (strange wording!) for the Maiden three dates ago.  As it continues to pick up in pro-grade rate, Saturn reaches stationary in a couple of days.  The result will be that of a faster and faster catchup during the summer.  Here are the three this evening, with Saturn at almost its closest to Spica (4.8º).  It will appear about this close for the next two months.

Detailed

   By August, although it will not be a very close encounter for Saturn and Spica, the star will form a near equilateral triangle with the planets in a binocular field.  As Mars continues to catch up with Saturn, try predicting when in August the two will have their closest meeting, and when the triangle will be closest to equilateral.
   Why a triangle?  There will be arc-like configurations as well that fit in binoculars.  However, with Spica being a first magnitude star and similar in magnitude to both planets, a triangle will be--perhaps arguably--be the most interesting configuration.  Since the star is near the ecliptic, planets "visit" it often, normally one after another.  When two planets come this close to the same star, especially with magnitudes similar, that is much more rare.  After this year, with Saturn taking 28+ years to return to Spica and Mars taking 650+ days to come back to it, these two will not revisit Spica as a triangle again until August 2042.  Since that is so far away, I will leave it at that for now! 
   Sticking with this evening, on a similar topic involving other close separations with Mars, take a look at this second image and the star near the planet: Zavijava (Beta Virginis) magnitude 3.6.  Looking at the celestial plot I put in that 5º binocular view, look at how Mars is about to get very close to this star-- 4 evenings from now, and worth putting a telescope on!  Despite that, Mars spends this evening even closer by a few arc-minutes, with another dimmer Virgo star (6.9 in magnitude).  The two are only 8 arc-minutes apart.  The separation between Mars and Zavijava will be 13 arc-minutes at best the evening of the 27th, and I will show them then.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Mercury, Moon and "twin" stars

Event Date: June 22nd
Time: 9:00 PM


Brief

   Mercury is close to greatest elongation (g.e.), setting 69 minutes after the Sun.  This means that is does not set below the horizon until 10:13, which is about 15 minutes short of of the end of astronomical twilight.  As we look towards the west-northwest during the first 30+ minutes after Sunset, there will be too much glare to see +0.1 magnitude-Mercury.  By the middle of nautical twilight, Mercury is finally easily visible.  At dimmer magnitudes to its right and a little further north, is the star Pollux, and its twin Castor, marking the two Gemini heads.  The namesake constellation is hard to see during this second half of June, with all other stars Sun-washed out or not bright enough to see with the eye.  Below, are the twin stars with Mercury and the waxing crescent Moon to Mercury's left and up a bit.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   Notice that at its current phase, that the Moon is low to the horizon.  With the Sun just slightly less than its best declination of the year, being two evenings past the June solstice, the Moon is not as far north.  It's orbit (not included this time to avoid interference with Mercury's) puts it at its most southern ecliptic latitude at this position.  Although it will gradually gain ecliptic latitude in a few days, it will move through the part of the sky that the Sun does at the time of the September equinox.  Since at that time, it moves south quickly, as will the Moon.  By the time the Moon reaches gibbous phase and then almost full, it will be seen in the same part of the sky as the last couple of full Moons.
   For one other note on Mercury, look for it forming a slight arc with Castor and Pollux.  If you read this entry early and look outside at the trio 2evenings earlier, the arc seems less obtuse.

Sun's local path since March equinox

Event Date: June 21st
Time: 7:00 PM


Brief

   With the summer solstice having passed yesterday, I having been talking alot about the Sun's position relative to the stars, constellations and celestial latitude.  For today, I will show a reminder of the Sun's position each evening at the same time.  I showed this last season by means of the analemma, for which the local path traces out a figure-8 shape, with one loop appearing larger than the other.  Last month, I showed part of that and this time, I will show one-quarter of it; since the March equinox about three months ago.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   The path doesn't seem very long relative to the stretch of azimuth: just south of west to west-northwest.  However, this is also because it slows down in moving north each day between the March equinox and June solstice.  If I was to show a stretch from mid-February to mid-April, that is only two months as opposed to three, yet the path would be about as long.  With the Sun increasing faster in declination during these weeks sandwiching the equinox, we can make sense of that.  For this path, notice the plots become closer together as we approached the solstice, which supports what I am referring to with the slowing of declination increase.

June solstice

Event Date: June 20th
Time: 4:09 PM

Brief

   It is officially summer at the time above for the northern hemisphere.  In relation to the Sun's path, our star crosses 90º in ecliptic latitude just 2 seconds earlier, from our point of view.  Since the southern hemisphere starts its winter season, it is most appropriate to call this the June solstice.  I defined all the terms for celestial and ecliptic guidelines back on the March equinox.  Saving at least an hour of repeating all of that, you can refer back to that at the link above.  Below are two images of the Sun alone a yellow line; green on top of red, using light-color combination.  For both, I enhanced the boldness of the gridlines so that they could be seen more easily against the daytime sky.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

Just as a reminder, which I mentioned the the March equinox journal, the solstice does not happen at 6 (h)ours of right ascension, although the timing is close to that for when the Sun reaches 90º in ecliptic longitude.  It reaches the 6h mark this year about 7 minutes earlier, just after 4:02 sharp.  As a result of precession of the Earth's axis, there are very rare times for which a solstice may occur for both within a minute or even seconds of each other.  If I find that to happen sometime over the years if I continue this blog long enough, I will for sure mention it!
As a final note for the second image above, it is a little easier to see how the 90º line goes directly through the Sun's disc, seemingly splitting it in half.  I set the clock back two seconds to 4:08(.58) which as mentioned in the brief, is when this happens.

Venus, Jupiter and Taurus' stars

Event Date: June 19th
Time: 5:30 AM

Brief

   One of the best things about Venus and Jupiter's bright magnitudes, currently at -4.2 and -2.0 respectively, is that the glare of the Sun only affects them if they are too close to our star.  As they separate themselves by even a small amount such as 20-25º, with only a fair geometry of the east-northeast sky for the morning, they become a little more visible.  As mentioned a few days ago, Venus slowly waxes (6% this morning) while Jupiter will continue to slowly brighten noticeably every couple of months; it approaches opposition this fall.  Along with the planets in this part of the sky, the 1st magnitude star Aldebaran is a little over 3º from Venus, with the soon-to-go-prograde bright planet to come closer to it by late June and early July.  This shows in image one further down.

Detailed

   On June 17th for the zoom-in image, I introduced  the 3rd magnitude star Epsilon Tauri (EpTau), which Venus makes its closest angular approach with this morning.  See the *second image for that, following the aforementioned zoom-out of the planet/star quartet.  EpTau and Venus are close enough in that one that with Venus' brightness, the star will be figuratively overshadowed, with a separation of 0.2º.

Venus spends a short amount of time in days near EpTau, and will come back to it the same way that it will come back to Aldebaran.  Whereas it will come closer this time to Aldebaran however than the first time, it will not come as close to EpTau as this time.  As Venus reaches each star, I will get further into angular separations.  The stars and Venus will be further separated from the Sun by then.  Although the sky will not be completely dark anymore by the time they escape atmospheric pollution, it will be dark enough in twilight to still see Aldebaran and EpTau in a telescope and binoculars.  Try fitting all four in binoculars early enough before Sunrise this morning as well, as all fit in a field of 10º.  An 11º field is recommended for slightly better centering.  Wide field binoculars can provide these fields, although that means low magnifications of perhaps under 10x.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

  *Venus is unlabeled in the second image so to not distract from the planet's young, waxing crescent phase.  Start observing it again before Sunrise, and watch it wax daily!

Venus, Jupiter and Moon's "tight fit"

Event Date: June 17th
Time: 5:34(.30) AM

Brief

   Tonight is part three of the Venus-Jupiter-Moon configuration series; the three brightest objects in the morning or evening sky when the Sun is below the horizon.  Yesterday, Jupiter was precisely between the other two by a little under 9º for a short time.  Since then, the Moon has moved further east against the stars, passed very close to Jupiter as seen from locations in eastern South America, as well as western Africa and Europe.  As seen at some locations on the globe, the Moon occulted Jupiter, grazed the planet, or became very close to either.  This evening, we see the three grouped together in a field slightly smaller than 9º.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed



Venus continues to close in on Jupiter, with the conjunction worth looking forward to in early July.  Can you predict the exact date, after watching Venus speed towards it in retrograde?  Hint: Venus is slowing down in retrograde yet very gradually, while much slower moving Jupiter is still moving somewhat quickly in pro-grade.
   In the next image, I will show a star that may be barely visible near Venus as it starts to escape atmospheric pollution: Aldebaran, which we saw often in the evening sky during the evening.  At the time, I was featuring of the Winter Circle, is starting to escape the glare of the Sun.  Venus is moving away from the star gradually with its retrograde movement now, yet will revisit Aldebaran again starting the second week of July.  When it does, we will see the two closer together and better placed with a larger separation from the Sun.  Until that time, enjoy Venus close with Jupiter, which is much brighter than Aldebaran.
   The field of view of Venus and Aldebaran is 5º with the two currently about 3.1º apart this morning.
Also seen in the field, dimmer Epsilon Tauri (magnitude 3.5) is only about 0.9º apart from Venus.  In two evenings, they have their closest encounter, and I will reveal the minimum separation then.

Mercury setting late, gradually

Event Date: June 18th

Time: 8:33(.35) PM

Brief

   It has been a few days since our previous look at Mercury.  It is getting close to greatest elongation, and also close to the end of its best evenings of apparition for this cycle.  With the geometry of the western sky not as good as that during February and March, it also means that Mercury is about the same declination as the Sun; it was about 8-9º further north during the early March greatest elongation week.  Here is Mercury in orbit relative to the ecliptic, looking west-northwest at Sunset (time above). 

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   Mercury sets 97 minutes after the Sun, meaning that if you want to wait for the Sun to get a little lower and less glare in the sky, there is some time for that before Mercury gets too low into atmospheric pollution.  It is 16º in altitude at the time of Sunset, meaning that even in a location with a little obstruction, it is still possible to pick it up with optical aid, being magnitude (-0.1).  Since it is further from perihelion now, that means that it is seen further separated from the Sun and therefore, a greatest elongation at month's end which will be more than the March one (about 26º vs 18º respectively). As it moves closer to aphelion, along with the almost solstice-Sun setting as late as it does, it means that Mercury will not reflect quite as much light to our eyes.  As it continues to wane in phase from its 62% illumination this evening, the dimming rate will increase quickly.  It may still be an object to pick up a week from now in optical aid, although viewing with the eye will be of a small window of time.  Catch it now, while still brighter than magnitude 0, and a decent enough apparition.

Jupiter between Venus and Moon

Event Date: June 16th
Time: 5:34(.30) AM

Brief

   At precisely the time above, we see the Moon close in enough to Jupiter, that the giant planet is exactly between it and Venus.  The separation from both is about 8.9º, although seeing it a few minutes before or after will appear the same.  I am showing Jupiter exactly centered only to show how interesting it is!  Below, here is how they appear, with Venus still emerging a little more each day from the Sun.

Detailed

  Since the Moon moves about one diameter per hour (about 1/2º) west to east against the stars, it spends the rest of the day catching up with Jupiter further.  In some locations towards the opposite side of the world, the Moon is seen occulting Jupiter.  As the second image below shows, with the ecliptic and the Moon's orbit visible, Jupiter is seen very close to the the path of the Moon.  I doubled the view from full zoom to 50% to show the [arrow-shaped] node more clearly.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

*Some parts of the world may see the crescent phase of our satellite either graze Jupiter, or pass anywhere from one to several arc-minutes away.  Since the Moon passes Jupiter while both are below the horizon for our location, we miss the close encounter.  However, when we feature the two with Venus tomorrow, we still get a very good presentation of the three!

Venus, Jupiter and the Moon "in line"

Event Date: June 15th
Time: 5:30 AM

Brief

   Almost as quickly as we saw Venus disappear into the Sun's glare during the second half of May, we are seeing it emerge now and waxing.  It is only 3% illuminated yet still large enough in angular size to be visible through atmospheric pollution.  It will slowly brighten a little each morning also, which is the reverse of what we witnessed after greatest magnitude and brilliancy dates last month.  Venus is 14º separated from the Sun.  Below is the image of the two together.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

  The separation between Venus and the Sun will continue to grow as Venus continues in retrograde.  Besides that, remember that Jupiter is rising about 3 1/2 minutes earlier than the Sun each day this week and Venus closes in on it more each day.  The two are 9 1/2º apart now, which is a little more than double their separation at closest, shortly after the beginning of Summer.  Venus will wax more by then and once again be a fine telescope target.  If using binoculars over the next few weeks, the crescent shape may be just barely visible, considering the low magnification of binoculars compared to most amateur telescopes.  Once they become close enough towards the end of the month, I will show them in a smaller binocular field.  They will never be close enough to view together in most telescopes; the lowest f-ratio of telescopes with long focal-length eye-pieces may beable to by then, depending on the exact size of the field.
   Finally, look to the upper right of Venus and Jupiter where a crescent shape much larger than Venus is seen waning and currently 14% illuminated.  There, we see the Moon, which visits the planets in a tighter grouping two days from now.  Tomorrow, I will show it lined up with Venus and Jupiter as seen from Earth, which I will elaborate on then.

Mercury's evening apparition

Event Date: June 14th
Time: 9:00 PM

Brief

   Mercury continues to emerge from the Sun in the west-northwest.  Look for it still high enough above atmospheric pollution during the end of civil twilight, and still an impressive magnitude of -0.4.  Since the planet sets an hour and a half after the Sun, thanks to a declination slightly higher than the Sun's and becoming more separated, we have about 30 minutes to see it easily with the eye, and another 20-30 minutes sandwiching that span with optical aid.  Here is Mercury during the last minutes of civil twilight.

Detailed

   As I often remind, viewers high enough up to not have obstruction in the way are able to see it for longer durations than those with obstruction.  As a waning gibbous, we are seeing a decent amount of Sunlight still reflecting off of its disc.  As the evening geometry becomes worse in this part of the sky over the next several weeks, along with Mercury's dimming, this is the last week to see it with the eye alone after Sunset; it will sink deep into atmospheric pollution.  It passed perihelion at about the time of superior conjunction, meaning that as it continues to approach aphelion over the next few weeks, it will start dimming very rapidly.  After greatest elongation, it will be nearly lost from naked eye view for the rest of the time east of the Sun this month and early July.  We will get it back in better view starting in late July when it is west of the Sun again in the morning.
   This second image shows the gibbous phase of Mercury 70%.  This waning will be gradual between now and inferior conjunction. I left the planet unlabeled below, to avoid distraction from viewing the small size compared to other planets.  The angular size is 6.1 arc-seconds, with an 8 arc-minute field.

click on images to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

the June morning sky during civil twilight

Event Date: June 13th
Time: 5:14(.51) AM

Brief

   Ending a three-morning series showing each phase of twilight beginning, the time for the image shows that for civil twilight's start; when the Sun is 6º below the horizon and a short while before rising.  As I mentioned at the end of yesterday's entry, I will include the celestial grid this time to show why I talk about an average duration of each twilight phase.  Looking at the grid, with the horizon showing, I also hid the landscape panorama.  This way, we can see that the further north the grid circles get, the less of a "slope-up" the Sun makes while rising.  Only the Andromeda Galaxy remains labeled, as the other deep sky that I labeled over the last two mornings are either too small in angular size to easily see, or become washed out by the Sun.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   Here's a review from two entries ago: the further north of east the Sun rises, as  the case of this time of year, the less of a slope during astronomical twilight.  The angle that the Sun rises relative the rises starts small and stays that way a little longer than at the equniox.  At this time of year for most mid-northern latitudes, the duration of astronomical is about 43 - 44 minutes, while nautical is 39 - 40 minutes.  Civil ends up being the shortest, at only 31 - 32 minutes.  The slight variance for each, hence my using two number values, depends on the exact date and/or latitude.  During the winter once again, these durations are shorter and different in comparison to each other
   Now that we have reached our earliest Sunset, our star will start rising later, although very gradually by seconds, during the rest of this month.  Rather than me posting the Sunrise time each day or mentioning it, try doing so yourself when looking east-northeast.  Even if there is hill, house or tree obstruction, we will notice a difference between now and the end of the month.

more on northeast deepsky sights

Event Date: June 12th
Time: 4:35(.47) AM

Brief

   As mentioned at the end of yesterday's detailed section, I previewed for today's entry a bit, as a continuation.  Now as seen below, we see the sky more blue than black in the image; sounds like an injury update, I know!  Getting back to astronomy, the time shows the start of nautical twilight.  Since the Sun rises only two seconds earlier and moves less than 4 arc-minutes further north, the beginning of nautical twilight is about the same as it would be yesterday if I did two journals on the same day.  I kept the same deep sky objects labeled as yesterday, while some others are just beginning--or about--to clear the horizon.  We will see lots of these much more clearly as they become further separated from the Sun during the summer, while they rise in the evening during the fall.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   The start of nautical twilight happens 44 minutes later than astronomical.  This makes sense...if you remember my numerous showings of the celestial graph of course, pointing near the north axis.  As the Sun rises further north of east each day, that means that time time below the horizon has it approaching the horizon more and more gradually.  As it gets closer to the horizon between nautical and civil twilight starts (12 and 6º respectively) and then civil to Sunrise, the times become shorter.  That is why yesterday if you recall, I mentioned an average time of the twilight phase durations, rather than each individually at this time of year.  I will remind with the celestial grid tomorrow, and put it in the image as we conclude this 3-part series of starting twilight in the northeast.  With the Sun rising close to its most north-of-east azimuth mark and the earliest Sunrise happening at our latitude tomorrow, it will be a fitting time to show that.

Deep-sky viewing before twilight: northeast

Event Date: June 11th
Time: 3:51(.45) AM

Brief

  Let's back the clock earlier to a darker hour-- for this time of year anyway!  With the Sun rising only a few seconds later than its earliest of the year for our latitude (which happens on the 13th), that means that shortly before 4 AM, the sky is already starting to slowly lighten in the northeast.  Looking south and southwest, it still seems dark enough.  However, if you are deep sky viewing in the north and eastern skies, your targets will become harder to see with the unaided eye.  A telescope can pick them up longer, depending on their magnitudes.  Looking towards that part of the sky, I labeled a few to keep in mind, including one of the most popular: the Andromeda Galaxy, which became high enough to view last month low in the northeast.  The brighter in magnitude, the more bold the label (e.g. Andromeda vs close by M32).  If you want to learn more about these objects and what they look like magnified, there are various websites to do so, and a good one can be found here:

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   The time above shows the official time that the sky is at its darkest, although a split second before astronomical twilight begins; when the Sun is at the 18º mark below the horizon.  It tangents and crosses the horizon for official Sunrise time at 5:46(.12) AM, almost 2 hours later.  Therefore, each phase of twilight, with nautical and civil to follow astronomical, all about 38-39 minutes long on average.  Near the first day of winter in December when the Sun is just as far south as it is north this week, twilight is only about 30 minutes per phase.
   Tomorrow, I will show this same part of the sky at the start of nautical twilight.  At that time, with the Sun 6º closer to the horizon, these deep-sky'ers will be more challenging to see even with powerful, portable-sized telescopes.  Give it a try however!

Venus emerging from Sun, nearing Jupiter

Event Date: June 10th
Time: 5:40 AM


Brief

  Venus is a very "young" crescent right now, as it begins the reversal of what we saw it do for most of the last 9 months: waning during that time span, and then disappear into the glare of the Sun until it transited our star.  At the time of transit, if you had a chance to view it with safe equipment, you would have seen the side of Venus that was not illuminated by Sunlight.  Of course, the side that was, faced the Sun.  Now, as the planet is just barely visible before Sunrise in optical aid this week rising in the east-northeast, it will start to wax gradually and brighten a little more each day.  Unfortunately with the Sun's glare, it will not be easily visible to the eye for about two more weeks, and even if before that, deep in atmospheric pollution.  Take a look here, as while being a little more south of the Sun, it rises only twenty two minutes earlier.

click on image to enlarge: courtesy of Starry Night Pro Plus, version 6.4.3, by Simulation Curriculum Corp.

Detailed

   As Venus is still moving quickly in retrograde motion, that means two good things for us as viewers: (1) the planet emerges from the glare of the Sun and by month's end, much easier to see.  (2) despite Venus moving a little further south of the Sun each day, we are at a point along the ecliptic shown above, that the Sun is almost finished moving north.  Therefore, Venus doesn't have that far south to move either.
   Also in the eastern sky during the next several days, we can observe Jupiter to Venus and the Sun's upper right (west), as it rises about four minutes earlier each morning.  While it is now starting to become a better dawn target, Venus' retrograde means that it will get closer with much slower moving Jupiter, which is moving the other direction in prograde at a good rate.  As a result, the two will have another impressive conjunction as they did March 13th.  They will not be as high as then, and a little further apart, yet still worth noting given their apparent magnitudes.  Even more attractive, will be these two in trio with the only other celestial body brighter than them before Sunrise: the Moon!  Look forward to next week, as the Moon wanes to a crescent and comes almost directly in between the two planets.  I know...tease tease!