Archives For July 2016
We hosted a small group of 16 visitors during the July 16 Open Night but enjoyed the event very much; a group of that size is in the not-too-large and not-too-small range that affords easy conversation and sharing of the observatory experience. I the summertime we usually feature Earth’s Moon. Between summer’s late sunsets, and Daylight Saving Time extending twilight by an hour, the Moon reliably shows up even before the sky is dark! Saturday’s experience was no exception.
We viewed the Moon through the Cooley Telescope’s remarkable optics and were rewarded with exciting detail. Moving along as the sky darkened, we turned our attention to Saturn: the planet’s subtle color and distinctive ring system showed good detail, very good at times. We briefly viewed Mars but the Red Planet is rapidly parting company with Earth and has grown small in the telescope’s eyepiece.
Yes, the “star” of the night was Luna and, once the last visitors departed, we made a few images of our nearest neighbor in space to help illustrate why we love sharing the view!
Stephens Memorial Observatory of Hiram College will be open for public observing Saturday, July 16, from 9:30 to 11:00 PM. Beautiful ringed Saturn, Earth’s amazing Moon, and hopefully the M4 star cluster in Scorpius will be the featured objects. Mars is rapidly distancing itself from us and will likely be uninteresting in our telescope though we may take a look anyway.
Sky conditions, of course, will determine what we see and even whether we can see anything at all. We will hope for clear skies because Saturn still presents its ring system at an excellent tilt for viewing!
No reservations are required and there is no admission fee for observatory public nights. Cloudy skies at the starting time cancel the event and, in that case, the observatory will not open.
The Observatory is located on Wakefield Road (Rt. 82) less than a quarter of a mile west of Route 700 in Hiram.
There is no parking at the Observatory. Visitors may park on permissible side streets near the Post Office, a short distance east of the observatory. DO NOT park on nearby Peckham Avenue; parking is prohibited there and violators may be ticketed!
NASA’s Juno mission, launched nearly five years ago, will soon reach its final destination: the most massive planet in our solar system, Jupiter. On the evening of July 4, at roughly 9 PM PDT (12 AM EDT, July 5), the spacecraft will complete a burn of its main engine, placing it in orbit around the king of planets.
During Juno’s orbit-insertion phase, or JOI, the spacecraft will perform a series of steps in preparation for a main engine burn that will guide it into orbit. At 9:16 PM EDT (July 4), Juno will begin to turn slowly away from the sun and toward its orbit-insertion attitude. Then 72 minutes later, it will make a faster turn into the orbit-insertion attitude.
At 10:41 PM EDT, Juno switches to its low-gain antenna. Fine-tune adjustments are then made to the spacecraft’s attitude. Twenty-two minutes before the main engine burn, at 10:56 PM, the spacecraft spins up from two to five revolutions per minute (RPM) to help stabilize it for the orbit insertion burn.
At 11:18 PM, Juno’s 35-minute main-engine burn will begin. This will slow it enough to be captured by the giant planet’s gravity. The burn will impart a mean change in velocity of 1,212 MPH (542 meters a second) on the spacecraft. It is performed in view of Earth, allowing its progress to be monitored by the mission teams at NASA’s Jet Propulsion Laboratory in Pasadena, California, and Lockheed Martin Space Systems in Denver, via signal reception by Deep Space Network (DSN) antennas in Goldstone, California, and Canberra, Australia.
After the main engine burn early July 5 (Eastern Daylight Time), Juno will be in orbit around Jupiter. The spacecraft will spin down from five to two RPM, turn back toward the sun, and ultimately transmit telemetry via its high-gain antenna. At Jupiter’s current distance of 536.9 million miles from Earth, radio signals will take about 48 minutes to reach the DSN.
Juno starts its tour of Jupiter in a 53.5-day orbit. The spacecraft saves fuel by executing a burn that places it in a capture orbit with a 53.5-day orbit instead of going directly for the 14-day orbit that will occur during the mission’s primary science collection period. The 14-day science orbit phase will begin after the final burn of the mission for Juno’s main engine on October 19.
JPL manages the Juno mission for NASA. The mission’s principal investigator is Scott Bolton of Southwest Research Institute in San Antonio. The mission is part of NASA’s New Frontiers Program, managed at the agency’s Marshall Space Flight Center in Huntsville, Alabama, for NASA’s Science Mission Directorate. Lockheed Martin Space Systems in Denver built the spacecraft.
Learn more about the June mission, and get an up-to-date schedule of events, at: