CLOSE
NASA/Bill Dunford
NASA/Bill Dunford

Look Up! The Southern Delta Aquariids Meteor Shower Is Here

NASA/Bill Dunford
NASA/Bill Dunford

Wake a few hours before sunrise tomorrow and you can start your day with some shooting stars. The Southern Delta Aquariid meteor shower is peaking this week, and while it's not the brightest show of the year, conditions are good and the moonlight is minimal. Provided you live in an area lacking light pollution, you might be in for quite a treat.

Consider this shower to be the big warmup for the Perseids next month. You might even see a Perseid or two tonight (though it's not like they're labeled; just stick with probability when you tell everyone what you saw). So where did these meteors come from, and what's going on up there?

BUZZING THE SUN

Comet Machholz recorded on March 1, 2005
Comet Machholz as recorded on March 1, 2005
NASA/JPL-Caltech/U. Washington/J. Morgenthaler

The Delta Aquariids are suspected to be the debris of 96P/Machholz, a sungrazing comet that orbits the Sun every 5.3 years. Sungrazers are the fighter pilots of the comet world, buzzing perilously close to the face of the Sun as they go about an orbit. Machholz is their Chuck Yeager. The comet's perihelion—that is, its point closest to the Sun in its orbit—is 0.1 astronomical unit. This puts it far closer to the Sun than Mercury, whose perihelion is 0.3 AU. (Earth is 1 AU.) When Machholz is at aphelion—its maximum distance away from the Sun—it reaches 5.9 AU, which is beyond even Jupiter's orbit.

It gets weirder yet. The comet's orbital inclination is 58 degrees. Rather than circle the Sun along the orbital plane of most planets (think of the light bulb and marble-on-wires model of the solar system from grade school), it is swooping up and away pretty dramatically. This adds up to a comet without fear, and as it goes about its orbit, it leaves behind a debris field of dust and sand-sized particles. That's where the Earth comes in. Every year as we travel our orbit, we cross through Machholz's trail, slamming into those particles at tens of thousands of miles per hour. When they burn up in our atmosphere, we get the stunning light show we call a meteor shower.

SEEING IT

As the shower's name implies, its radius—the seeming point of origin in our night sky—is the constellation Aquarius. Don't limit yourself to looking specifically in that area, though; all the sky is a meteor's canvas. You should give your eyes 30 minutes to adjust to the darkness. Bring a blanket and scan about 45 degrees up from the horizon. That's where the most action will begin to be apparent. Good news if you live in the southern hemisphere (or if you live near the equator in the northern hemisphere): You will get the best viewing of anyone on Earth.

The meteors should be visible until sunrise. If you oversleep or the weather is bad, try again tomorrow night. This shower doesn't have a pronounced peak like others, and you have a fair chance of catching something if you stick with it in the days ahead. The next big meteor shower will be the Perseids, which will peak on the night of August 12.

arrow
Space
The Fascinating Device Astronauts Use to Weigh Themselves in Space

Most every scale on Earth, from the kind bakers use to measure ingredients to those doctors use to weigh patients, depends on gravity to function. Weight, after all, is just the mass of an object times the acceleration of gravity that’s pushing it toward Earth. That means astronauts have to use unconventional tools when recording changes to their bodies in space, as SciShow explains in the video below.

While weight as we know it technically doesn’t exist in zero-gravity conditions, mass does. Living in space can have drastic effects on a person’s body, and measuring mass is one way to keep track of these changes.

In place of a scale, NASA astronauts use something called a Space Linear Acceleration Mass Measurement Device (SLAMMD) to “weigh” themselves. Once they mount the pogo stick-like contraption it moves them a meter using a built-in spring. Heavier passengers take longer to drag, while a SLAMMD with no passenger at all takes the least time to move. Using the amount of time it takes to cover a meter, the machine can calculate the mass of the person riding it.

Measuring weight isn’t the only everyday activity that’s complicated in space. Astronauts have been forced to develop clever ways to brush their teeth, clip their nails, and even sleep without gravity.

[h/t SciShow]

nextArticle.image_alt|e
iStock
arrow
fun
Watch Astronauts Assemble Pizza in Space
iStock
iStock

Most everyone enjoys a good pizza party: Even astronauts living aboard the International Space Station.

As this video from NASA shows, assembling pizza in zero gravity is not only possible, it also has delicious results. The inspiration for the pizza feast came from Paolo Nespoli, an Italian astronaut who was craving one of his home country’s national dishes while working on the ISS. NASA’s program manager for the space station, Kirk Shireman, sympathized with his colleague and ordered pizzas to be delivered to the station.

NASA took a little longer responding to the request than your typical corner pizzeria might. The pizzas were delivered via the Orbital ATK capsule, and once they arrived, the ingredients had to be assembled by hand. The components didn’t differ too much from regular pizzas on Earth: Flatbread, tomato sauce, and cheese served as the base, and pepperoni, pesto, olives, and anchovy paste made up the toppings. Before heating them up, the astronauts had some fun with their creations, twirling them around like "flying saucers of the edible kind,” according to astronaut Randy Bresnik.

In case the pizza party wasn’t already a success, it also coincided with movie night on the International Space Station.

[h/t KHQ Q6]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios