Clear skies for the rest of the week

Clear skies are in store for us for the rest of the week and maybe into the weekend.  It’s a great time to get out and observe the night sky!  We can hope this morning’s 38 degree temperatures have discouraged the bugs from returning.

A great place for a list of what to see is at Sky and Telescope’s web site.  Here’s a few highlights:

The moon won’t be back until later next weekend, but wide-ringed Saturn is still available, low in the southwest for a few hours after sunset. If skies are stable without much haze, you should be able to see at least two moons, Titan and Iapetus, in a telescope.

In dark skies, the Northern Cross, overhead, shows where the Milky Way is located.

Find the faint constellation, Camelopardalis, the Camel, in the northern sky and use binoculars to see comet C/2017 O1.  It’s almost overhead in the morning sky.

Sunrise comes later, so it’s a bit easier to get up to see the morning sky, with Venus and Mars.  The Orionid meteor shower adds about 10 fast-moving meteors to the mix, peaking on the Saturday morning, the 21st.

 

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First time we’ve sighted the cause of a gravitational wave event.

“‘This gamma ray burst has an interesting friend. . . . Buckle up,’”

With these words (and other cryptic messages), astronomers around the world were asked to check a certain location for other signs of an unusual event, in this case where a source of gravitational waves had been detected in optical wavelengths.

What a wonderful way to send a message that tells the recipient that something tremendously important is going on that they need to check in to, but doesn’t give away the whole story.  (I’m assuming the ‘interesting friend’ was detection of its gravitational waves, which they couldn’t talk about because it takes a long time to confirm the observation and do the mathematics for gravitational wave measurements.)

It reminds me of coded message sending out word that Enrico Fermi had performed the first controlled sustained nuclear fission chain reaction “…the Italian Navigator has just landed in the New World…” 12/2/1942.

Thank God for our ability to use methods conventional (optical astronomy) and sublime (gravitational wave detection) to observe and theorize about events like this!

The articles I used for this note:

https://www.washingtonpost.com/news/speaking-of-science/wp/2017/10/16/gravitational-waves-neutron-stars-kilonovas-what-the-new-physics-announcement-means/?utm_term=.f92bd0531256

https://www.washingtonpost.com/news/speaking-of-science/wp/2017/10/16/scientists-detect-gravitational-waves-from-a-new-kind-of-nova-sparking-a-new-era-in-astronomy/?utm_term=.695c0e3c2c2e

Check out some original sources of the news:
https://www.nasa.gov/press-release/nasa-missions-catch-first-light-from-a-gravitational-wave-event
http://hubblesite.org/news_release/news/2017-41
http://www.skyandtelescope.com/astronomy-news/astronomers-catch-gravitational-waves-from-colliding-neutron-stars/

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When neutron stars collide, this is what it might look like. (Robin Dienel/Carnegie Institution for Science)

 

 

Moon morning photos

The dew point dropped overnight and you could see it in the blue skies as dawn arrived this Tuesday morning.  I rushed out with my camera and telescope to greet the blue skies and the clear view of the waning gibbous moon.  Drier weather will continue through the weekend.  Temperatures Tuesday will still be warm, but with noticeably less humidity.   It’ll moisten up a bit at times with a chance of showers late Wednesday through Thursday morning and some coastal clouds and drizzle and scattered showers into the weekend, followed by more warming.  While temperatures will be near to above normal, the combined temperature and moisture won’t approach last week’s muckyness.

Here’s some photos from this morning.

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What the moon looks like in binoculars. Hand-held photo of moon with 250mm telephoto lens, 1/320 second exposure at f/8 and ISO 200.

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Venus (lower left). The sky is too bright to catch Mars in the photo. Hand-held Canon XS 1/160 second exposure at f/8, ISO 200.

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Moon through the telescope. Canon XS enhanced with attached 2x barlow lens, 1/80 at ISO 200.  This is what the eye can see at 40 power through a telescope.

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Canon with double barlow to enlarge the view; 1/50 sec ISO200.  Larger, but not much more detail.  The view through the telescope with a high power lens is like this, but in real life, much sharper as the eye compensates somewhat for fuzzy focusing.

 

 

 

 

Leaves are falling – feel like Fall yet?

The leaves may be falling, but it doesn’t feel much like Fall yet! Tropical air came around the high pressure system offshore and tropical system Nate added more moisture.

The National Weather Service notes in the Monday, 5pm Weather Forecast Discussion:

Lows tonight should once again be near normal highs for this
time of year. Depending on the temperatures right before
midnight, maximum low temperatures could be set once again at
area climate locations. Refer to the climate section of the AFD
for these records.

Lows in the upper 60s, when average highs in early October are in the upper 60s! We need the air conditioning just to take the humidity out of the air.  That’s why it’s so cold in stores and supermarkets.  With highs ‘only’ in the 70s, we don’t need lower temperatures as much as lower humidity.

Cooler air comes in for the second half of the week, then we still have some warmer air to come next week.

In this chart, for late Wednesday, the jet stream is predicted to be well north of us. (The red dashed lines are how much higher than normal (and thus warmer) is the height at  500mb, roughly at the half-way point of the height of our atmosphere. Blue are lower than normal heights.

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By next Monday, the jet stream wiggles south a bit and the heights are not so out-of-normal.  cpc_NAM_f192wbg

Oh, Nate!

Oh.  Nate.  Sigh.  The perhaps-soon-to-be-Hurricane Nate is messing up travel plans to Louisiana and nearby places along the Gulf Coast of the United States.

Weather computer models are consistently showing Nate crossing the Louisiana coast late Saturday / early Sunday as a tropical storm.  The National Hurricane Center is, prudently, not wanting to overlook the super-warm water in the Gulf of Mexico and the lack of wind shear, each contributing to strong development of Nate after it gets knocked down a bit bumping to the Yucatan Peninsula.

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What about New York metro area?  The National Weather Service NYC office is seeing a scenario where tropical air was going to get sucked up the east coast of the United States and a possible rainmaker for Sunday night/Monday morning.  THEN comes Nate, or, at least, Nate’s leftovers, for Tuesday-ish. In the meantime, cold fronts will pass through our area, coming back as warm fronts, coming back as cold fronts and then as a warm front bringing the tropical air.  As you might notice, the windshield-wiper effect of fronts whipping through our area will give us warm, cloudy and occasionally showery weather through the weekend, as the back-and-forth nature of these frontal passages leaves us with weak frontal systems.  Definitively cooler air is possible after Tuesday’s sweep of the wiper blade, which may include pieces of Nate as part of the picture.

 

Heads UP! for October 2017

Heads UP! for October:  So many planets seem to have stage fright this month.  Mercury and Jupiter are hiding in the sun’s glare,  Saturn is low in the southwest, Venus is low in the dawn sky, but still dazzling, even near its dimmest.  Mars is very dim as it climbs past Venus, both across the solar system from us.

Use a Solar Observatory for Watching Planets!

The hidden planets can be found using the Solar Heliographic Observatory (SOHO) as they appear to trespass into the most intense solar glare.  Mercury will pass through SOHO LASCO C3 instrument from right to left during almost all of October, and be caught by the narrower view of LASCO C2 for a few days from the 6th through the 11th.

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10/3/2017 view from SOHO C3. Mercury to the right of the Sun (which is blocked; the sun is the size of the white circle).

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Sun, Mercury and morning planets as seen from Earth 10/3. Via NASA Solar System Simulator. Extra Credit: Can you pick out the asteroid Vesta in the C3 image? Using the animated GIF may help as Vesta (and Mercury) move against the background stars.

Jupiter nearly passes behind the sun from our point of view.  It’s visible after midmonth in the C3 (October 16th through November 5th) and in the C2 from the 24th through the 28th.  Spica takes Regulus’ place as the bright star in the C3 field this month.

Comets!

Comet P96 Machhotz is streaming into the inner solar system, reaching perihelion by Oct 27 passing inside the orbit of Mercury.  It get as bright as magnitude +2, but it (too!) will be in the Sun’s glare from Earth’s point of view.  Use the SOHO C3 to see it sweep through from bottom to top of C3 field October 25th through 30th.   For nighttime observers, there is a well-placed comet in the northern skies.  C/2017 O1 was discovered in photos from July 19th taken for the All-Sky Automated Survey for Supernovae (ASASSN) program.  O1 is forecast to brighten perhaps +6 or 7 as it passes perihelion beyond the orbit of Mars in October.  O1 is up all night, but highest in the morning as it moves from between Perseus and Auriga into the Camel (Camelopardalis).  Its green color is from diatomic carbon and may be visible in telescopes.  It’s even more likely to show up in time exposures.

What’s a bright object fan to do?

Stay inside and watch the SOHO feed?  Look for Saturn, sliding into the haze and fog in the southwestern sky.  It sets before 9pm by the end of the month.  The Moon comes by to provide consolation on the 22nd and 23. Consider that the earlier darkness and lingering warmth makes October a good month to show off the brighter stars and Saturn to crowds of people, so all is not lost.

Saturn Sights!

Saturn’s rings are still tilted wide open at 27 degrees, the largest for 2017. Titan makes two trips around Saturn each month. Iapetus is not as bright as Titan, but still visible in most telescopes.  It’s brightest when it is furthest west of the planet, around mid-month. It’s nice to see another place in our Solar System where humans have left our marks, thanks to the Cassini/Huygens mission.

Venus, Tiny, but Bright!

Venus is trying to hold on to its place in the pre-dawn sky, rising less than two hours before sunrise.  It’s a not-quite-round blob in the telescope, 90 percent illuminated this month, while shrinking in size.  Mars and Venus are less than the apparent size of the Moon apart on the morning of the 4th.  Mars is less than half the apparent size of Venus, because it ‘s a bit smaller and further away; and much dimmer at magnitude plus 1.8 vs. Venus’ minus 3.9.  The Moon joins the morning party on the 17th and 18th.

Moon Photobomb!

The Moon takes its revenge on Regulus for photobombing the total solar eclipse by eclipsing Regulus in the dawn sky on the 15th.  Regulus will disappear behind the Sunlit crescent about 544am and reappear on the Earthlit edge about 643am. Sunrise is 707am.

Dark Mornings Late!

Early risers, we can use daylight time to our advantage.  The latest sunrise of the year, according to clock time, occurs in the last week of the month.   Even earlier risers at 4am will get to see Orion standing up high in the southern sky.  Orionid meteors are an early morning bonus with up to 10 more meteors an hour than usual on the 21st and a day before and after.  Orionids are some of the fastest meteors of the year.  A few Taurid meteors may show up in advance of their November peak.  You can tell Taurids from the Orionids, since most Taurids are bright and slower moving.

Space Station Stats

 

The International Space Station is an evening object through the 18th and a morning object starting on the 29th.   Check for the latest updates on the orbit of the Air Force space plane.  Based on its present orbit, visible overflights are likely in the evening sky.  At 400km altitude, the X-37B could be seen crossing our skies at magnitude +1 or 2.

Saturn – lower but still fine!

Saturn is sinking lower in the southwestern sky, following the Scorpion and leading the teapot-shaped Sagittarius.  Tonight (Wed. Sept. 27th) our Moon is a bit to the left of Saturn, making it easier to find.  Saturn is the brightest object in that part of the sky.  Saturn will be hanging out there for the next month or so, getting lower in our sky, so this is a good time to catch Saturn in your telescope.

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In a telescope, Saturn’s rings are just about as wide open as they get this year.  Saturn’s brightest moon, Titan is north of the planet. Most of Saturn’s other moons are closer to the planet, and hard to see with the rings being so bright now.  Iapetus is fainter than Titan, but findable ahead and south of the planet.  Follow it from night to night as it moves west and gets a bit brighter.  Use brighter Titan to figure out which way is north in your telescope or move the scope a bit ‘up’, which will drive it a bit north.

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Iapetus is harder to see because it’s smaller than Titan and it has two very different sides – one reflects only five percent of the Sun’s light and the other side reflects 50 percent! (Our moon reflects 12 percent. )  So Iapetus is easier to see when the reflective side points toward Earth. That happens when Iapetus is on the west side of Saturn. If you are watching in your telescope, west is the direction the stars and planets seem to move in the sky as the Earth rotates.   Iapetus will be farthest west of Saturn in mid-October, so it will be brightest then.

Useful apps for finding Saturn’s moons, that include wide-ranging and variable in brightness Iapetus, are NASA’s Solar System Simulator (as seen above) or the British Astronomical Association’s Saturn Moon App   (see below).  On my iPhone, the Sky and Telescope Saturn Moon app also includes Iapetus.

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