What's Up? with the StarGeezer

Here comes Fall!

  Friday, September 23rd brings the Autumnal, or Fall, equinox. The exact moment of the equinox will be 9:06 Universal time or 5:06 am EDT in the Americas. At that moment the tilt of Earth's axis will cause the Sun's apparent position to glide across the equator into the southern hemisphere. The Fall equinox marks the beginning of the Fall season in the northern hemisphere and Spring south of the equator.

At the equinox of the seasons I always recommend that you observe sunrise or sunset and make a mental note of the Sun's position on your horizon. Do the same around the winter or summer solstice and compare your observations!

Juno is on the way to Jupiter

 

 

NASA's Juno mission to Jupiter left Earth on a five year, 1.7 billion mile journey which promises to give us great insight into the solar system's Big Daddy. Read more here and see Jupiter for yourself early mornings before dawn. Head outside any morning before twilight and look for the bright "star" high in the southeast. That would be Jove. Your binoculars will show Jupiter's "Galilean" moons just as he saw them 400 years ago. Steady your binocs on a porch post or the corner of a building.

What's Up in August?

 

August brings the last half of summer, the best time to view Neptune and an asteroid called Vesta. We'll say goodbye to Saturn and hello to Jupiter and, believe it or not, there are celestial signs that winter isn't that far off. This month is a great time to view the heart of our Milky Way galaxy and some of my favorite constellations. Read more here.

Image left: NASA/JPL/Dawn image of asteroid Vesta. This asteroid is one of the oldest objects in our solar system. The Dawn spacecraft arrived at Vesta last month and will spend the next year surveying the baby planetoid.

Watch the meteors Saturday morning

 

The Delta Aquarid meteors will peak on Saturday morning, July 30th. Activity should pick up after 10pm Friday night and be best between 3am local time and morning twilight Saturday morning. Get comfortable on a blanket or lawn recliner in the darkest spot you can find and watch the darkest part of the sky high in the southeast. Depending on haze and skyglow at your location expect to see up to 10-15 meteors per hour.

Learn more here

New Moon, Old Moon

One of my favorite observing activities is spotting very "old" or very "new" crescent moons around the time of a "new" Moon or the beginning of a new "lunation". Many amateur astronomers make sport of this activity. The next "new" Moon happens at 18:39 UT, 2:39 PM EDT Saturday, July 30.

 

I captured this shot of a very "old" waning crescent on Friday morning, July 29th some 32 hours before Luna glides between planet Earth and the Sun. You'll have to look closely to pick out the very slender lunar crescent. Tip, the Moon is just above the highest branch on the conifer tree. Look for a waxing crescent after sunset on Tuesday, August 2nd.

Learn more here

Catch ISS, the Moon and Jupiter Sunday morning

Another series of visible morning passes of the International Space Station is beginning. Sunday morning, July 24th much of the southeastern US will be treated to a fine southwest to northeast pass.

For observers here in Louisville, ISS will appear above the southwestern horizon at 6:06:57 AM, peak at 65 degrees off the southeastern horizon at 6:10 and continue to the northeast. I checked visibility and this pass should be visible for folks east from Dallas and Chicago. For those in the central time zone the pass happens a few minutes after 5am. New York city, looks like ISS will fly almost directly over your head!

If you venture out Sunday morning enjoy the view of the Moon with Jupiter just above and to the right of the waning crescent Moon, high above the eastern horizon!

We're furthest from the Sun, so why is it Summer?

Early July marks two annual milestones in Earth's annual trip around the Sun.

On July 2nd at 12 hours UT (8:00 am EDT) will be the mid-point for the year 2011.

 

On Independence day, July 4th at 15 hour UT (11 am EDT) Earth will reach APHELION, the furthest distance from the Sun. Earth's orbit is slightly oblong so the distance from the Sun varies as we circle our star.

Ironically we're nearest the Sun in January and furthest here in July. So why is it Summer when we're furthest from the Sun? What's up with that?

Seasons are all about the tilt of Earth's axis. We're tilted about 23 degrees from the vertical.  During the summer season the northern hemisphere is "leaning in" toward the Sun while the southern hemisphere is tilted away. It's winter in the southern hemisphere.

Watch the ISS anytime you like...almost

Near the northern summer solstice most, if not all night ISS passes are visible because of the high sun angle here in the northern hemisphere. Here are some of the best during the coming week.

Sunday, June 12 11:16-11:22 pm WSW > NE peaking at 48 degrees off the NW horizon

For other pass times click here

Pass times listed are for Louisville, KY.

Shuttle Endeavour and ISS flying together. An amazing sight!

Early Memorial Day morning I watched as Shuttle Endeavour and the International Space Station orbited overhead, flying in formation. It was an amazing sight. Read the story here

Update! Watch ISS and Shuttle Endeavour flying in "formation" Monday morning

I just noticed that Shuttle Endeavour will undock from the International Space Station on Sunday night. This means you will have the chance to see the Endeavour and ISS flying "in formation" on Monday morning! This is a very rare, and final, chance to see Endeavour in orbit.

Learn more here