Today Jupiter passes through superior conjunction, passing behind the Sun as seen from our vantage point here on Earth. The planet is currently lost in the Sun’s glare and unobservable, it will reappear in the dawn sky during the first week of July.
Category: Sky Events
Sky events
Mercury and Venus
Over the next few days Mercury and Venus will pass by each other one last time in a dance that has lasted over a month. Tonight the pair are about 2°04′ apart. Tomorrow that will shrink to 1°55′ and widen the following night to 2°03′.
After the 21st, the pair will separate rapidly as Mercury dives into the sunset to inferior conjunction on July 9th.
Mercury and Venus
With the Moon and Jupiter having departed the sunset stage, Mercury and Venus continue their dance. This evening finds the two about 4° apart with the dimmer Mercury higher in the sky. Mercury has dimmed over the last few weeks and is now only 0.7 magnitude, far dimmer than Venus at -4 magnitude.
Over the coming days the pair will draw closer, passing within 2° on June 19th. As the month wanes the two will then separate ending the dance.
The SuperMoon is Back
I saw it on Facebook first, shared by a family member… The meme that will not die…
The claims are the usual… The Moon will be huge in the sky. The Moon will be closer than is has been in some huge time span.
There is some truth here, the June full Moon will be a bit bigger and brighter than usual. And it will be closer to the Earth than it has been in a long time, if you consider 27.5 days to be a long time.
The SuperMoon meme exaggerates the truth to varying degrees.
It all relates to lunar apogee and perigee. As the Moon’s orbit is elliptical, it does get a little further and closer during each orbit, but the difference is fairly minor, the distance varies from 405,000km (251,000miles) to 360,000km (223,000miles) from the Earth. This difference in distance results in the Moon appearing up to 12% larger at perigee compared to apogee. For a better explanation you can go to another post that explains this more fully, with graphics.
12% difference, noticeable if you look close, but hardly a “SuperMoon”.
The Moon passes through perigee, the closest point every 27.5 days, about once each orbit. Not a very long time. But SuperMoon only occurs if perigee happens to coincide with full Moon. As these two cycles are usually out of sync with each other people do not usually notice. About once a year the two cycles coincide and we get a slightly larger, brighter full Moon… The SuperMoon. Interesting, but not as dramatic as the hype.
Geologists have studied the lunar earthquake/volcano possibility for decades with varying results. Indeed, some older studies seemed to indicate a link. More recent studies have pretty much ruled out any association, better data associated with more instrumentation and improved worldwide coverage has shown that if there is any effect it is quite small.
Besides, if there were a link, the earthquakes should occur every 27.5 days as the Moon passes through perigee, they do not. There is no reason to make anything special of the full Moon/perigee synchronicity.
June 23rd will offer a nice, bright full Moon. A great time to take a moonlit walk, or a night dive. Ignore the scaremongers, and use this as an excuse to enjoy our beautiful universe.
Mercury at Maximum Elongation
Today Mercury reaches maximum elongation, the furthest point it will reach from the Sun in our sky and the highest it will be above the sunset for this evening apparition. The planet is easily visible as a bright, starlike object about 24° above the setting Sun as twilight begins. Over the next couple weeks Mercury will slide back into the sunset, heading for inferior conjunction on July 9th.
The Moon, Mercury and Venus
This evening the Moon will join the ongoing dance of planets in the sunset. A very thin crescent Moon will be 13° above the horizon at sunset and 6° below and south of the brilliant Venus. 5° above Venus will be Mercury notably dimmer at only 0.4 magnitude.
Tomorrow the Moon will be a bit higher and show a little more crescent at 6% illuminated. It will be above Venus and about the same elevation as Mercury, if 7° further to the south.
Jupiter is still present, but probably too low into the sunset to spot at only 6° from the setting Sun. Maybe with perfect conditions?
New Moon
Mars Appears in the Dawn
This week Mars will appear in the dawn sky having passed through superior conjunction on April 17. Look for a 1.5 magnitude object to rise around 04:50, about 10° ahead of the Sun. The red planet will see opposition in April of 2014.
Tomorrow morning a very thin crescent Moon will share the dawn. Rising about 05:05 a 1% illuminated Moon will be 3° below Mars, closer to the rising Sun.
Jupiter Exits the Evening Sky
Jupiter is quickly sliding into the sunset heading for superior conjunction on June 19th. This evening the planet will be 10° above the setting Sun, in the next few days it will disappear into the glare. Look for Jupiter to reappear in the dawn during the first week of July.
Mercury, Venus and Jupiter
This evening will see a line of bright planets in the sunset. Easiest to spot will be the brilliant Venus, shining at -4 magnitude and 15° above the setting Sun. 4°30′ below Venus will be Jupiter, quite low in the sunset, but bright enough to spot at -2 magnitude. 4°16′ above Venus will be Mercury, notably dimmer at -0.2 magnitude. The three will form an almost perfect line of bright objects in the glow of sunset, it should be a nice sight.