Skytalk

Science takes center stage Saturday, April 22 in marches planned across the country. Philadelphia will host its own local science march from City Hall to Penn’s Landing.

The Philadelphia Science Festival begins Friday, April 21. The festival brings 80+ free or nearly free activities and programs to locations all over the city. The 10 day long event culminates with the city-wide astronomy night on the 28th and the Science Carnival at Penn’s Landing on the 29th.

Jupiter, Mars and Saturn are all visible in the night sky this week.

Ever since Pluto was demoted from the pantheon of planets, efforts have intensified to designate a replacement. Scientists have detected the presence of…something…about 10 times the mass of Earth and 1000 times the distance between the Earth and the Sun. Australian researchers mounted a campaign to find the big guy using the SkyMapper telescope at Siding Spring Observatory. The search yielded hundreds of thousands of images that were then sifted by tens of thousands of volunteers, and out of that pile have emerged 4 candidate objects that might be the elusive Planet Nine.

Mars after sunset in the west, Jupiter by 9 p.m. in the east and Jupiter, Saturn, and Venus at 5:15 a across the sky.

The Night Sky Observatory at the Franklin Institute this Thursday evening features astrophysics powerhouse and scientific visualization specialist Dr. Frank Summers.

A star has been discovered that orbits a black hole once every 28 minutes. Not impressed? This star is 2.5 times farther away from the black hole than the moon is from Earth, and the moon orbits the Earth only once every 27 days.

Scientists believe they have discovered a new way that stars are formed. A black hole spits out particles and gases at a blistering 94 million miles per hour. That seems pretty fast, until you realize that’s only 14% of the speed of light. Scientists think that new stars could be formed in those high-speed jets of matter.

President Donald Trump’s proposed 2018 budget cuts NASA’s funding by 1%. What’s lost? Some Earth Observing missions, the Asteroid Redirect Mission, and the NASA Office of Education.

Monday was an important day for folks who are sick of winter—the Vernal (or Spring) Equinox! The tilt of Earth’s rotational axis allowed for equal hours of daylight and darkness.

What does this look like at the equator? At the North Pole? How about the South Pole? Little discrepancies distort the true meaning of the word “equinox.” The hours of daylight and darkness are more equal at the equator than at the poles.

Pan,  Saturn’s ‘flying saucer’-shaped moon was photographed by the orbiting Cassini spacecraft. This orbits as a shepherd moon in the 325-mile-wide space known as the Encke Gap.  See images here: https://saturn.jpl.nasa.gov/galleries/raw-images/

Venus is almost gone from the night sky; it exchanges positions with Mercury while Mars is still hanging. Jupiter well up by 10 PM. Pre-dawn Saturn and Jupiter sit in the south and south-western sky at 5:45 AM.

This week, Derrick focuses attention on the contributions of minorities and women to the field of astronomy.

There are many birth anniversaries of note this week:

Venus is sinking into the west – don’t miss it !

Daylight Saving Time kicks in at 2 a.m. on Sunday, March 12.

Philadelphia Mayor Jim Kenney honored Chief Astronomer Derrick Pitts with an award for his life achievements in a ceremony on Friday, March 3. The event featured 12 writers of the Boys and Girls Club, who recently penned the new children’s book “Derrick Pitts, Astronomy Superstar.”

Out of the new administration comes a directive that NASA initiate a study to determine if the first test flight of NASA’s new heavy-lift launch vehicle, scheduled for late 2018, can be converted into a manned circumnavigation of the moon in 2019. Meanwhile, SpaceX has announced its plan to send two paying astro-tourists on a one-week flight around the moon next year.

As more and more planets are being discovered, it’s not a bad idea to come to a consensus on answering the question, “What’s a planet?” A new definition of ‘planet’ was suggested by a nationwide team of astronomers led by graduate student Kirby Runyon at Johns Hopkins University.

Just another day in the Universe: Discovery of White Dwarf Pulsars

The twin 10m Keck telescopes at Mauna Kea in Hawaii have identified 100 more exoplanet candidates. One of them is just 8.3 lightyears away!

What country holds the record for the most satellites launched on a single launch vehicle? India! Last Tuesday, the Indian Space Resource Organization launched 104 nano satellites; 3 from India, 13 from several European countries and 88 E-O sats from a US company, Planet Labs. They are 1000 times lower in weight than legacy communication satellites, and are imaging the entire landmass of Earth every day.

Jupiter is rising in the late evening now. Venus still commands the southwest sky after sunset with Mars standing by.

Believe it or not, Orion and the winter circle are losing their sky dominance to the spring constellations Gemini, Cancer, and Leo. There are only 30 more days until the Vernal (Spring) Equinox.

We celebrate two giant birth anniversaries this week: Wednesday is the 453rd anniversary of Galileo and Sunday is the 544th anniversary of Copernicus’ birthday. Galileo proved by observation what Copernicus suggested as the structure of the solar system. Interestingly, 404 years ago, the Roman Catholic Church censored Galileo to keep him from distributing science truth to the general population in an attempt to maintain tight control over church doctrine.

We all agree Mars was warmer and much wetter in its past, but how? We’ve just assumed that Mars was like Earth early on. On Earth our atmosphere’s had enough CO2 as a greenhouse gas to keep the planet warm enough for water to exist on the surface as a liquid. Studies of rocks by Curiosity at Gale Crater and analysis from orbit indicate there isn’t enough carbonate rock to indicate there was enough CO2 in Mars’ atmosphere to keep the surface warm enough for liquid H2O to exist as the rock record shows. So what heating mechanism? There are other greenhouse gases (methane, SO2, NO) but they don’t last very long.