Tureis (Rho Puppis)
Tureis (Rho Puppis) is a star in the constellation Puppis, magnitude 2.8.
A pulsing star that keeps time every 3 hours 23 minutes — the model for a whole class.
Every 3 hours and 23 minutes, Tureis swells and shrinks, brightening and dimming as it goes. Olin Eggen announced the pulsations in 1956, making it one of the first known Delta Scuti stars, and records going back to 1946 show the rhythm keeping steady time. At about 6,650 K it is one of the coolest stars of its kind.
Its chemistry is odd too. Its spectrum shows weak calcium but strong lines of other metals, and it has more than twice the Sun’s share of heavy elements. It is the prototype of the Rho Puppis stars: aged stars with this peculiar mix. Most such stars have a partner, but Tureis seems to be alone.
Its name is Arabic for “little shield”, once shared with Iota Carinae, now called Aspidiske. About 394,000 years ago Tureis passed about as close to us as Procyon is today; it is now moving away.
Tureis (Rho Puppis) is 64 light-years away: the light we see from it set off in 1962, 5 years after Sputnik became the first artificial satellite.
Did you know?
- A magnetic pulsator. In 2017 astronomers found a magnetic field around Tureis, making it only the second Delta Scuti star known to have one.
- A cold ring of dust. Extra infrared light hints at a disc of dust around the star, at about 85 K — roughly 50 times the Earth–Sun distance from it.
A yellowish-white star of magnitude 2.8 in Puppis, about 20 degrees east-south-east of Sirius. It pulses every 3 hours 23 minutes, changing by about 0.15 magnitudes — too little to judge by eye, but measurable with a camera.
When and where to see it
It is best placed in the evening sky around February, when it crosses the meridian at about 10 pm local time (around midnight in January). It can be seen from everywhere south of 66°N and never sets south of 66°S.
At its highest it stands 16° up from 50°N, 31° up from 35°N, 66° up from the equator, 79° up from 35°S.
Facts
- Type
- Star
- Constellation
- Puppis
- Designations
- Rho Puppis, ρ Pup, 15 Pup, HR 3185, HD 67523, HIP 39757
- Magnitude
- 2.8
- Position
- RA 8h 7.5m, Dec −24° 18′ (J2000)
- Spectral type
- F5IIkF2IImF5II
- Colour
- yellow-white (B−V 0.43)
- Distance
- 64 light-years
- Discovered
- Known since antiquity; Olin J. Eggen announced its pulsations in 1956
Open AstroPilot to see when Tureis (Rho Puppis) is highest tonight from your location, how easy it is with your telescope or binoculars, and an eyepiece view.