What’s happening in the sky?
July 1: The month starts out with Venus and Jupiter really close to each other, low in the western sky. Follow them as they move apart during the month.
July 14: Mark your calendar. The New Horizons space craft passes Pluto. 6-7:15pm—NASA TV program.
The New Horizons spacecraft will send a preprogrammed signal after the close approach. The mission team on Earth should receive the signal at about 7:02pm when New Horizons “phones home.”
Venus has been approaching Regulus in Leo since the start of the month; tonight it comes closest.
July 18: Just after sunset you should be able to see Venus Jupiter, Regulus, and the slender crescent moon close to each other.
July 22-23: The first quarter moon is close to the bright star Spica to the right on the 22nd and to the upper left on the next night.
July 25: The moon is close to Saturn.
July 30: Meteor shower of the Delta Aquariid; a bright moon will interfere with the fainter meteors.
July 31: The second full moon of the month: a Blue Moon!
Hello Earth, can you hear me?
The European Space Agency says its comet lander, Philae, has woken up and contacted Earth. Philae, the first spacecraft to land on a comet, was dropped on to the surface of Comet 67P by its mothership, Rosetta, last November. But it bounced once and bounced again, landing in the shade of a cliff. No sunlight was a killer. It worked for 60 hours before its solar-powered battery ran flat. The comet has since moved nearer to the Sun and sunlight has reached Philae to work again.
The lander tweeted the message, “Hello Earth! Can you hear me?” Now, it appears as though Philae has been awake for a little while, but had been unable to contact Earth until now.
Philae contacted Earth, via Rosetta, for 85 seconds on Saturday in the first contact since going into hibernation in November. Philae is doing very well. It’s been a long seven months. There are happy people on planet Earth.
The plan is to start with the least risky experiments, such as using instruments to “sniff” the atmosphere of the comet to determine its chemical content. The most ambitious goal will be to rotate the lander in order to give its drill access to the ground. There was an attempt to use the drill when the lander first touched down on 12 November 2014, but it was too far from the surface of the comet to reach the surface, because it became wedged against a cliff partially on its side. It is hoped that by getting Philae to rotated itself and change its position the drill can be brought closer and collect samples of comet material directly from beneath the surface. This is potentially extremely interesting because this kind of cometary material could have brought the conditions for life to the surface of the earth.
One huge problem is the gas and dust that is now streaming from the comet as its surface is being heated by the increasingly intense sunlight it is encountering. The Rosetta “mother ship” is lying a safe distance away, but to receive messages from Philae it will need to maneuver closer to the comet. The last time is was close in April, it was like driving a car through a heavy snow storm. The sensors on the space craft keep its antennas aligned with Earth using detectors sensing stars. The detectors were confused by the bright particles and contact with Rosetta was briefly lost. The plans are now for Rosetta to make several dives in toward the comet to retrieve data from Philae. Wish them luck!
July 14 is Pluto Day
On June 14, a month before July’s encounter, a 45-second thruster burst refined New Horizons’ trajectory toward Pluto, targeting the optimal aim point some 7,750 miles above Pluto’s surface.
Telemetry indicated that the maneuver performed as planned, reaching Earth through NASA’s Deep Space Network at 6:23am EDT. The spacecraft was nearly 2.95 billion miles from home, and radio transmissions traveling at the speed of light took 4.5 hours to reach Earth.
The New Horizons team will continue to analyze spacecraft navigation and tracking data with an eye on June 24, which would be the next opportunity for them to adjust course. New Horizons is now less than 22 million miles from the Pluto system, or less than 100 times as far from Pluto as the moon is from Earth. The spacecraft is healthy and all systems are operating normally.
Because the close approach will take the spacecraft inside the orbits of all five of Pluto’s known moons, the orbits of those moons needed to be known accurately. A collision with a moon would be disastrous. The recent observations have detected all five known moons, and have found no rings or hazards of any kind.
“Every day we break a new distance record to Pluto, and every day our data get better,” says mission Principal Investigator Alan Stern of the Southwest Research Institute, Boulder, Colorado. “Nothing like this kind of frontier, outer solar system exploration has happened since Voyager 2 was at Neptune way back in 1989.”
Alan Stern is not giving up on his belief that Pluto still deserves to be a planet. “If it looks like a duck, swims like a duck, and quacks like a duck, then it’s probably a duck,” jokes Alan Stern, principal investigator for the New Horizons mission. To him Pluto looks like a planet. The spacecraft will take the first ever close-range photos and scientific readings of the former planet, revealing continents, mountain ranges, frozen oceans, even ice volcanoes. Who knows right now? It could provide the evidence that could return Pluto to the ranks of planets.