Have you seen them? There’s been a quintet of good reasons to awaken early this past week, as the February dawn sky hosts all five classical planets, very nearly in order: Mercury, Venus, Mars, Saturn and Jupiter. For a few days, the waning crescent Moon even joined the show on the weeks leading up to New on February 8th. Fleeting Mercury breaks the streak later this week, exiting the dawn sky as it heads towards superior conjunction on the far side of the Sun on March 23rd. Continue reading “Stunning Images of the February Dawn Planetary Line-up from Around the World”
Watch the Moon Beat a Path Across the Hyades Tonight
“Once more, unto the breech…” Ready to brave the February cold and the ongoing arctic polar express? Tonight, North American skywatchers will witness an encore event, as the waxing gibbous Moon crosses the Hyades star cluster and – for a lucky few — occults the bright star Aldebaran. Continue reading “Watch the Moon Beat a Path Across the Hyades Tonight”
Vesta Rules the February Dusk Skies
Missing out on the morning planetary action?
February sees all five naked eye planets in the dawn sky, though that’s about to change in March. But the good news is, now is the time to hunt for a sometimes planet, sometimes asteroid in the early evening. Continue reading “Vesta Rules the February Dusk Skies”
A Challenge in Visual Athletics: Hunting the Gegenschein
Looking for something truly elusive? Astronomy has no shortage of the fleeting and ephemeral when it comes to challenges. This week’s challenge will require supremely dark skies and persistence.
We’re talking about the gegenschein, the elusive counter glow lying opposite to the Sun across the plane of the ecliptic. Continue reading “A Challenge in Visual Athletics: Hunting the Gegenschein”
And Mercury Makes Five: See All Naked Eye Planets in the Sky at Once
A fine sight greets early risers this week into the month of February, as all five naked eye planets: Mercury, Venus, Mars, Saturn and Jupiter ring the sky from horizon to horizon.
Though not a true planetary alignment as extolled by many websites, this is a great chance to see all five classical planets above the horizon at once… or seven, if you count the waning gibbous Moon and the rising Sun, as the ancients did as part of their geocentric, Earth-entered universe. You can kinda see how they got there, as the very heavens themselves seemed to whorl about the cradle of earthly human affairs. Continue reading “And Mercury Makes Five: See All Naked Eye Planets in the Sky at Once”
Lights Out: A Fine Occultation of Aldebaran Spans the Atlantic
They braved the cold, cursed the clouds, wrestled with frozen telescope focusers and more, as dedicated astros worked to catch the first occultation of the bright star Aldebaran for 2016 by the waxing gibbous Moon.
The event went down last night into the wee hours of the morning, and was visible across North America into western Europe and the United Kingdom. Continue reading “Lights Out: A Fine Occultation of Aldebaran Spans the Atlantic”
Watch the Moon Occult Aldebaran Tuesday Night
“That’s no moon…”
But in this case, it is (sorry Ben), and that Moon is headed to temporarily obliterate (occult) the view of the bright star Aldebaran as seen from the Earth on the evening of January 19th and into the morning of the 20th.
Here are the specifics. Not to be confused with Princess Leia’s homeworld of Alderaan of Star Wars science fiction fame, the occultation of the bright star Aldebaran in the astronomical constellation Taurus occurs on the night of Tuesday, January 19th and finds the waxing gibbous the Moon 82% illuminated and four days from the first Full Moon of the year on January 24th. This is also the first of 13 occultations of Aldebaran for the year 2016, one for even lunation. Evening occultations are particularly favorable, as the star in question always disappears along the leading edge dark limb of the Moon, to reappear along its daytime limb. Once the Moon is waning, the reverse is true, as the bright limb then leads towards New phase.
We’ve caught occultations of bright stars very near Full, and can attest that it is indeed possible to follow a +1st magnitude star all the way to the lunar limb.
The occultation footprint runs across the nighttime northern hemisphere from the early morning hours in western Europe and the United Kingdom across the northern Atlantic, across the contiguous ‘lower 48’ states of of U.S. to Canada and northern Mexico. It actually juuuust misses us here down in sunny Florida, one of the few states that will miss out on the event. This is the best placed occultation of Aldebaran for 2016 for most North American viewers, falling during early evening prime time hours high in the post twilight sky.
Here’s the timing for the ingress (beginning) and egress (end) for the occultation for selected cities; the International Occultation Timing Association (IOTA) has an extensive table of times for cities within the occultation path. (all quoted using Universal Time(UT), plus altitude (alt) in degrees (deg) :
London
Ingress: 3:25 UT/alt: 6 deg
Egress: 3:57 UT/alt: 2 deg
Atlanta
Ingress: 2:22 UT/73 deg
Egress: 3:06 UT/70 deg
Boston
Ingress: 2:35 UT/60 deg
Egress: 3:47 UT/50 deg
Los Angeles
Ingress: 1:05 UT/40 deg
Egress: 2:13 UT/54 deg
Montreal
Ingress: 2:28 UT/59 deg
Egress: 3:42 UT/51 deg
Halifax
Ingress: 2:46 UT/53 deg
Egress: 3:57 UT/43 deg
Note that precise times for the event change slightly due to the position of the observer within various time zones, as well as the parallax shift of the Moon as seen from the Earth.
Occultations always give us a chance to analyze the target star for any possible close in binary companions, as the star winks out in a tell tale step-wise fashion. Aldebaran has no known close companion star, though spurious claims have been made for planets orbiting the star over the years. 65 light years distant, Aldebaran is in the direction of the Hyades star cluster in the distant galactic background, though it is physically unrelated to the group, which is 153 light years from the Earth. This also means that several bright stars in the Hyades get occulted by the Moon as well on Tuesday night, as the Moon makes its way to Aldebaran and its date with astronomical destiny.
An occultation of a bright star by the Moon also allows selenographers to map out the profile of the jagged lunar limb, as light from the distant star is alternately shines through the valleys and is occluded mountain peaks along the edge of the relatively nearby Moon. This effect can be especially dramatic for observers positioned along the graze line, which on Tuesday night runs from southern Georgia through southern Texas into northern Mexico, across to Baja California.
Recording the occultation is as simple as aiming a video camera coupled to a telescope at the Moon at the appointed time, and running video. Start early, and you may want to overexpose the waxing gibbous Moon a bit to bring out Aldebaran. We managed to nab the 2008 occultation of Antares by the nearly Full Moon using a simple JVC video camera and an 8” Schmidt-Cassegrain telescope.
The event will be easily visible using binoculars, and should even be noticeable to the unaided eye.
That’s it for this week in ‘things passing in front of each other…’ In astronomy, lots can be learn just from analyzing light, or in this case, the absence of it. What good are occultations? Well, they might just save your not-so-secret rebel base from immediate annihilation:
And watch that Moon, as there will be another good occultation of Aldebaran shifted just slightly westward next lunation on February 16th, 2016.
More to come!
Comet US10 Catalina: The Final Act
Have you seen it? 2016 has kicked off with a fine apparition of a binocular comet: C/2013 US10 Catalina. We’ve been following this icy visitor to the inner solar system the first few mornings of the year, a welcome addition to the morning planetary line-up. Continue reading “Comet US10 Catalina: The Final Act”
Watch Venus Brush Past Saturn This Weekend
Welcome to 2016! The early morning sky is where the action is this first week of the year. We were out early this Monday morning as skies cleared over Central Florida on our yearly vigil for the Quadrantid meteors. Though only a handful of meteors graced the dawn skies, we were treated to a splendid line-up, including Jupiter, Mars, Spica, Antares, Saturn, Venus, the waning crescent Moon AND a fine binocular view of Comet C/2013 US10 Catalina. Continue reading “Watch Venus Brush Past Saturn This Weekend”
Space Stories to Watch in 2016
2015 was an amazing year in space, as worlds such as Pluto and Ceres snapped into sharp focus. 2015 also underlined the mantra that ‘space is hard,’ as SpaceX rode the roller coaster from launch failure, to a dramatic return to flight in December, complete with a nighttime landing of its stage 1 Falcon 9 rocket back at Cape Canaveral. Continue reading “Space Stories to Watch in 2016”