tips and hints for observing asteroids

Near Earth Asteroids

image link to navigate to Astra's Stargate home page

Observing NEAs and Other Asteroids

How to Make Observations of Near Earth Asteroids

Observing asteroids is different from the other solar system objects you may have observed. These solar system objects are faint and are often moving quickly, so that the window for making observations may be quite short. This page contains hints and tips on observing Near Earth Asteroids.

Helping Observers to Find and Characterize NEAs

Links open a new window. Don't close the new window, return to this page and load the next link, it will open in the same new window. It's easy to follow links from the NEA pages without creating multiple pages. All links on the NEA pages at Astra's Stargate that leave the site work this way.

Happy Hunting!
- - Astra

Find out about the December 12th Occultation of Alpha Orionis, aka Betelgeuse on this page!

occultation design break

Hunting Asteroids From Your Backyard - an article with observing tips from Sky and Telescope by Dennis di Cicco.

Amateur Astronomers observe 2012 da14 - Turn your speakers down or up for the music that plays with this over view of an astronomical expedition to observe the crossing of 2012 DA14 in February 2013 from from J.D.Strikis

Asteroid Data Hunter - Armchair astronomers, discover new asteroids @home! NASA provides an app to identify asteroids in images.

Unique Asteroid Occultation Opportunity!

Betelgeuse Occulted by 319 Leona Main Belt Asteroid

December 12, 2023 - 1:17 UT

The tenth brightest star in the sky, Betelgeuse (Alpha Orionis) is a first-magnitude star in the constellation of Orion, about 650 light years away, although there is some uncertainty about its actual distance. It is a variable red giant star that is about 700 times larger than our own Sun. Betelgeuse is one of the best observed stars and it has caused quite a stir over the last few years due to notable dimming and brightening. As an old star, some have wondered if they will see it go nova in their lifetimes. This will only happen if the event has already taken place because light from Betelgeuse takes 650 years to travel to Earth.

319 Leona is a 14th magnitude main-belt asteroid orbiting the Sun about every 6.3 years. It was discovered in 1891, by the astronomer Auguste Charlois at the Nice Observatory. There is some uncertainty about the size and shape of the asteroid, but it is large ~70km in diameter. On December 12, Leona will interrupt the light heading toward Earth from Betelgeuse before it arrives at Earth, no matter how long ago it left the star. Recent occultations by Leona of distant stars have been improving our knowledge of the asteroid's dimensions. Leona presents no danger to the Earth as it orbits well beyond Mars, 2.7 AU away from the Sun.

Betelgeuse (Alpha Orionis)
First Hubble Image of Betelgeuse
Credit 1996, Deupree (CfA), NASA, ESA

To make scientifically meaningful observations of this event, an instrument with an aperture of 60 to 100 mm and a clock drive can be used. (More detailed images can be obtained with larger instruments.) As with a solar eclipse, the event has a centerline with areas to the north and south that will have partial coverage of Betelgeuse by the asteroid. In fact, it is not certain that Betelgeuse will even be totally covered because of uncertainties that remain regarding the actual sizes of the asteroid Leona and of Alpha Orionis. The International Occultation Timing Association (IOTA) collects data and coordinates observers for making these types of observations.

To be clear, for observers in Florida, U.S.A., 1:17 UT on December 12 will translate to 8:17 pm Eastern Standard Time (EST) on December 11, 2023. Observers in Mexico will have to adjust their occultation time accordingly. Observers in Europe, will be able to view the occultation a few seconds earlier as the occultation path crosses the Earth. The time of the occultation varies from 6 to 12 seconds, depending on where an observer is on the track of the occultation. Observers not on the centerline of the track will see only a partial occultation. Observations along the entire track are needed. A greater number of observations make the data more valuable.

Join the The Virtual Telescope Project 2.0 on December 12, 2023 at 01:00 UTC to view the occultation live from southern Italy!

occultation design break

Who Can See the Occultation?

The occultation of Betelgeuse by 319 Leona is very much like a solar eclipse. There is a narrow path of visibility with a centerline. Of course, observers on the centerline see the deepest eclipse. The occultation will only be seen in a narrow band across the planet. Observations from various astronomers or stations are combined together to make a more complete picture. Usually, asteroid occultation opportunities give Earth based astronomers a chance to find out more about the asteroid, but in this case we have an excellent opportunity to learn more about one of the most enigmatic stars we know. Betelgeuse rotates very slowly. It is believed to rotate once every 36 years! The convection cells inside the star may remain stationary for months, even years.

Path of Dec 12 occultation
Path of the Occultation across Earth
Image from ERC Lucky Star updated path

Observers in southern Florida and elsewhere will enjoy a sky that is moon free, but the constellation of Orion will be low on the horizon. Photometric observations are the best, but this event may be of interest to star gazers on the path of the eclipse. (Yes, occultations are eclipses!) Betelgeuse shines at magnitude 0.5. Betelgeuse is expected to drop 3 magnitudes, effectively glowing as a 3.5 mag star during deepest eclipse.

IOTA is looking for observations using filters R and V to detect Titanium(II) oxide (TiO bands); R and B filters for the chromosphere of Betelgeuse; and R and H-alpha for the extended atmosphere.

There is a North America Asteroidal Occultation Program website that is apparently part of IOTA. Use this link if you need an IOTA report form.

Future Asteroid Events - maintained by Derek C. Breit

Betelgeuse (Alpha Orionis)
Path of occultation through southern United States
Extracted from Google Maps from Future Asteroid Events

occultation design break

Occultation of Alpha Orionis Web Resources

Watch an Asteroid Block Betelgeuse: The Occultation of Betelgeuse by 319 Leona - from NASA Science News

occultation design break

Observe Asteroids

+ Minor Planet Electronic Circulars

Recent MPCEs

Find new discoveries or NEAs that require updated observations.

Wait! There's more . .

Observing Asteroids, NEOs and Comets from Las Cumbres Observatory Global Telescope Network

This page was updated by Dawn Jenkins, December 8, 2023.